Journal articles: 'Adaptive radiotherapy (ART)'

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LEE, Victor Shing-Cheung, Giuseppe SchettIno, and Andrew Nisbet. "UK adaptive radiotherapy practices for head and neck cancer patients." BJR|Open 2, no. 1 (November 2020): 20200051. http://dx.doi.org/10.1259/bjro.20200051.

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Objective: To provide evidence on the extent and manner in which adaptive practices have been employed in the UK and identify the main barriers for the clinical implementation of adaptive radiotherapy (ART) in head and neck (HN) cancer cases. Methods: In December 2019, a Supplementary Material 1, of 23 questions, was sent to all UK radiotherapy centres (67). This covered general information to current ART practices and perceived barriers to implementation. Results: 31 centres responded (46%). 56% responding centres employed ART for between 10 and 20 patients/annum. 96% of respondents were using CBCT either alone or with other modalities for assessing “weight loss” and “shell gap,” which were the main reasons for ART. Adaptation usually occurs at week three or four during the radiotherapy treatment. 25 responding centres used an online image-guided radiotherapy (IGRT) approach and 20 used an offline ad hoc ART approach, either with or without protocol level. Nearly 70% of respondents required 2 to 3 days to create an adaptive plan and 95% used 3–5 mm adaptive planning target volume margins. All centres performed pre-treatment QA. “Limited staff resources” and “lack of clinical relevance” were identified as the two main barriers for ART implementation. Conclusion: There is no consensus in adaptive practice for HN cancer patients across the UK. For those centres not employing ART, similar clinical implementation barriers were identified. Advances in knowledge: An insight into contemporary UK practices of ART for HN cancer patients indicating national guidance for ART implementation for HN cancer patients may be required

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Sonke, J. J. "SP-0436: The concept of adaptive radiotherapy (ART)." Radiotherapy and Oncology 111 (2014): S173. http://dx.doi.org/10.1016/s0167-8140(15)30541-7.

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Bak, Bartosz, Agnieszka Skrobala, Anna Adamska, Joanna Kazmierska, Natalia Jozefacka, Tomasz Piotrowski, and Julian Malicki. "Criteria for Verification and Replanning Based on the Adaptive Radiotherapy Protocol “Best for Adaptive Radiotherapy” in Head and Neck Cancer." Life 12, no. 5 (May 12, 2022): 722. http://dx.doi.org/10.3390/life12050722.

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No clear criteria have yet been established to guide decision-making for patient selection and the optimal timing of adaptive radiotherapy (ART) based on image-guided radiotherapy (IGRT). We have developed a novel protocol—the Best for Adaptive Radiotherapy (B-ART) protocol—to guide patient selection for ART. The aim of the present study is to describe this protocol, to evaluate its validity in patients with head and neck (HN) cancer, and to identify the anatomical and clinical predictors of the need for replanning. We retrospectively evaluated 82 patients with HN cancer who underwent helical tomotherapy (HT) and subsequently required replanning due to soft tissue changes upon daily MVCT. Under the proposed criteria, patients with anatomical changes >3 mm on three to four consecutive scans are candidates for ART. We compared the volumes on the initial CT scan (iCT) and the replanning CT (rCT) scan for the clinical target volumes (CTV1, referring to primary tumor or tumor bed and CTV2, metastatic lymph nodes) and for the parotid glands (PG) and body contour (B-body). The patients were stratified by primary tumor localization, clinical stage, and treatment scheme. The main reasons for replanning were: (1) a planning target volume (PTV) outside the body contour (n = 70; 85.4%), (2) PG shrinkage (n = 69; 84.1%), (3) B-body deviations (n = 69; 84.1%), and (4) setup deviations (n = 40; 48.8%). The replanning decision was made, on average, during the fourth week of treatment (n = 47; 57.3%). The mean reductions in the size of the right and left PG volumes were 6.31 cc (20.9%) and 5.98 cc (20.5%), respectively (p < 0.001). The reduction in PG volume was ≥30% in 30 patients (36.6%). The volume reduction in all of the anatomical structures was statistically significant. Four variables—advanced stage disease (T3–T4), chemoradiation, increased weight loss, and oropharyngeal localization—were significantly associated with the need for ART. The B-ART protocol provides clear criteria to eliminate random errors, and to allow for an early response to relevant changes in target volumes.

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Sale, CA, T. ffrench, and R. Voss. "Personalising margins for bladder radiotherapy." Journal of Radiotherapy in Practice 10, no. 2 (November 12, 2010): 137–40. http://dx.doi.org/10.1017/s1460396910000269.

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AbstractThis patient case study represents the introduction of adaptive radiotherapy (ART) at the Andrew Love Cancer Centre (ALCC) with non-uniform margins for invasive bladder cancer treatment. Invasive bladder cancer has historically had poor local control with radiotherapy treatment; however, with the introduction of cone-beam computer tomography (CBCT) and adaptive treatment, there is potential for improvements in disease control and reduced toxicities.

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Buciuman, Nikolett, and Loredana G. Marcu. "Adaptive Radiotherapy in Head and Neck Cancer Using Volumetric Modulated Arc Therapy." Journal of Personalized Medicine 12, no. 5 (April 21, 2022): 668. http://dx.doi.org/10.3390/jpm12050668.

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A dosimetric study was performed to show the importance of adaptive radiotherapy (ART) for head and neck cancer (HNC) patients using volumetric modulated arc therapy (VMAT). A total of 13 patients with HNC who required replanning during radiotherapy were included in this study. All plans succeeded to achieve the set objectives regarding target volume coverage and organ sparing. All target volumes presented a significant decrease with an average of 76.44 cm3 (p = 0.007) for PTVlow risk, 102.81 cm3 (p = 0.021) for PTVintermediate risk, and 47.10 cm3 (p = 0.003) for PTVhigh risk. Additionally, a positive correlation was found between PTV shrinkage and the number of fractions completed before replanning. Significant volume decrease was also observed for the parotid glands. The ipsilateral parotid decreased in volume by a mean of 3.75 cm3 (14.43%) (p = 0.067), while the contralateral decreased by 4.23 cm3 (13.23%) (p = 0.033). For all analyzed organs, a reduction in the final dose received after replanning was found. Our study showed that ART via rescanning, recontouring, and replanning using VMAT is essential whenever anatomical and positional variations occur. Furthermore, comparison with the literature has confirmed that ART using VMAT offers similar results to ART with intensity modulated radiotherapy.

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Glide-Hurst, C., and I. J. Chetty. "SP-0004 IMAGE-GUIDED ADAPTIVE RADIOTHERAPY (IGART): STATE OF THE ART." Radiotherapy and Oncology 103 (May 2012): S2. http://dx.doi.org/10.1016/s0167-8140(12)70343-2.

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Meldolesi, E., D. Lockman, D. Yan, and A. Martinez. "Geometric Evaluation of Image Guided Adaptive Radiotherapy (ART) for Prostate Cancer." International Journal of Radiation Oncology*Biology*Physics 63 (October 2005): S90—S91. http://dx.doi.org/10.1016/j.ijrobp.2005.07.157.

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Murthy, V. "Bladder preservation with helical tomotherapy-based, image-guided radiotherapy: A clinical study using “plan of the day” adaptive radiotherapy." Journal of Clinical Oncology 29, no. 7_suppl (March 1, 2011): 289. http://dx.doi.org/10.1200/jco.2011.29.7_suppl.289.

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289 Background: This clinical study assessed the potential of helical tomotherapy-based, image-guided radiotherapy (IGRT) to increase the accuracy of bladder irradiation using a plan of the day adaptive radiotherapy (ART) technique. Methods: Ten patients with stage T2b-T4- N0 M0, histologically proven bladder transitional cell carcinoma, who underwent bladder preservation with trimodality therapy in an ongoing trial, are reported. All patients received a dose of 64Gy/32# to the whole bladder. Seven of these also received a simultaneous integrated boost of 68Gy/32 fractions to tumor bed. The ART technique entailed the generation of six planning PTVs and thus six separate IMRT plans for each patient. All patients underwent daily pre and post treatment MVCT imaging to correct for positioning errors, choose the plan of the day, depending on deformation of the bladder, and verify intrafraction filling at the end of treatment. Margins needed to encompass the bladder wall in each direction during radiotherapy was determined in the following three scenarios: (a) centers with availability of daily IGRT and performing ART, (b) centers with IGRT not doing ART, and (c) centers without IGRT using electronic portal imaging for setup. Results: At a median follow-up of 12.2 months, all patients had a complete response in the bladder and one patient had a pelvic nodal recurrence. No patient developed treatment related grade 3 toxicity. Post treatment MVCT scans (n=315) were used to generate margins for centers with varying resources. Overall, the margin needed to encompass the anterior and superior walls 85 to 95% of the time was more than the other walls (Table, margins for six walls in cm). Maximum geographical miss in spite of IGRT was noted for the superior (13.8%) and anterior walls (10.3%). Conclusions: Plan of the day ART is a feasible and promising technique for optimal treatment and dose escalation in bladder cancer. [Table: see text] No significant financial relationships to disclose.

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Schwartz, David L., and Lei Dong. "Adaptive Radiation Therapy for Head and Neck Cancer—Can an Old Goal Evolve into a New Standard?" Journal of Oncology 2011 (2011): 1–13. http://dx.doi.org/10.1155/2011/690595.

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Current head and neck intensity-modulated radiotherapy (IMRT) techniques cause significant toxicity. This may be explained in part by the fact that IMRT cannot compensate for changes in the location of disease and normal anatomy during treatment, leading to exposure of at-risk bystander tissues to higher-than-anticipated doses. Adaptive radiotherapy (ART) is a novel approach to correct for daily tumor and normal tissue variations through online or offline modification of original IMRT target volumes and plans. ART has been discussed on a conceptual level for many years, but technical limitations have hampered its integration into routine care. In this paper, we review the key anatomic, dosimetric, and treatment delivery issues at play in current investigational development of head and neck ART. We also describe pilot findings from initial clinical deployment of head and neck ART, as well as emerging pathways of future research.

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Mulder, Samuel L., Jolien Heukelom, Brigid A. McDonald, Lisanne Van Dijk, Kareem A. Wahid, Keith Sanders, Travis C. Salzillo, Mehdi Hemmati, Andrew Schaefer, and Clifton D. Fuller. "MR-Guided Adaptive Radiotherapy for OAR Sparing in Head and Neck Cancers." Cancers 14, no. 8 (April 10, 2022): 1909. http://dx.doi.org/10.3390/cancers14081909.

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MR-linac devices offer the potential for advancements in radiotherapy (RT) treatment of head and neck cancer (HNC) by using daily MR imaging performed at the time and setup of treatment delivery. This article aims to present a review of current adaptive RT (ART) methods on MR-Linac devices directed towards the sparing of organs at risk (OAR) and a view of future adaptive techniques seeking to improve the therapeutic ratio. This ratio expresses the relationship between the probability of tumor control and the probability of normal tissue damage and is thus an important conceptual metric of success in the sparing of OARs. Increasing spatial conformity of dose distributions to target volume and OARs is an initial step in achieving therapeutic improvements, followed by the use of imaging and clinical biomarkers to inform the clinical decision-making process in an ART paradigm. Pre-clinical and clinical findings support the incorporation of biomarkers into ART protocols and investment into further research to explore imaging biomarkers by taking advantage of the daily MR imaging workflow. A coherent understanding of this road map for RT in HNC is critical for directing future research efforts related to sparing OARs using image-guided radiotherapy (IGRT).

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Li, Taoran, Xiaofeng Zhu, Danthai Thongphiew, W. Robert Lee, Zeljko Vujaskovic, Qiuwen Wu, Fang-Fang Yin, and Q. Jackie Wu. "On-Line Adaptive Radiation Therapy: Feasibility and Clinical Study." Journal of Oncology 2010 (2010): 1–12. http://dx.doi.org/10.1155/2010/407236.

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The purpose of this paper is to evaluate the feasibility and clinical dosimetric benefit of an on-line, that is, with the patient in the treatment position, Adaptive Radiation Therapy (ART) system for prostate cancer treatment based on daily cone-beam CT imaging and fast volumetric reoptimization of treatment plans. A fast intensity-modulated radiotherapy (IMRT) plan reoptimization algorithm is implemented and evaluated with clinical cases. The quality of these adapted plans is compared to the corresponding new plans generated by an experienced planner using a commercial treatment planning system and also evaluated by an in-house developed tool estimating achievable dose-volume histograms (DVHs) based on a database of existing treatment plans. In addition, a clinical implementation scheme for ART is designed and evaluated using clinical cases for its dosimetric qualities and efficiency.

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Kairn, T., M. Lathouras, S. R. Sylvander, J. V. Trapp, and S. B. Crowe. "Adaptive radiotherapy dosimetry in a challenging geometry: A model gas-filled tissue expander in a helical TomoTherapy beam." Journal of Physics: Conference Series 2167, no. 1 (January 1, 2022): 012012. http://dx.doi.org/10.1088/1742-6596/2167/1/012012.

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Abstract Helical TomoTherapy treatment and delivery systems (Accuray Inc, Sunnyvale, USA) allow off-line adaptation of radiotherapy treatments, with dose calculations that use MV computed tomography (CT) data acquired at treatment. This study aimed to assess the potential dosimetric effects of a gas-filled temporary tissue expander (TTE) on the accuracy of breast radiotherapy dose calculations from both the TomoTherapy treatment planning system (TPS), which uses kV CT data, and the TomoTherapy adaptive radiotherapy (ART) system, which uses MV CT data. A TomoTherapy treatment plan was created and delivered to a 3D-printed rectilinear model of a breast with implanted gas-filled TTE, including a stainless steel CO2 container, and film measurements of the delivered dose were compared against dose calculations from the TPS and ART systems. The film measurements showed that the TomoTherapy TPS provided comparatively accurate dose calculations in the ~550 cm2 volume of air that modelled the gas filling of the TTE and within the surrounding tissue-equivalent materials, except in regions where the beam was transmitted through the stainless steel CO2 container, possibly due to the volume of stainless steel being over-estimated in the kV CT images that were used to generate the treatment plan. The ART system provided more accurate dose calculations than the TPS in regions affected by the stainless steel container, but also over-estimated the dose in the air within the TTE. These results suggest that the TomoTherapy TPS and ART systems could be used to produce reliable dose calculations of breast treatments in the presence of gas-filled TTEs, if kV CT imaging options are chosen to avoid artefacts and minimise the need for density over-rides and if treatment targets that include only clinically relevant tissues, and exclude all TTE components, are used to evaluate and compare the doses calculated by both systems.

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Trovò, Marco, Annalisa Drigo, Andrea Dassie, and Imad Abu Rumeileh. "Adaptive Radiation Therapy in a Patient with a Massive Nodal Breast Cancer Recurrence." Tumori Journal 95, no. 4 (July 2009): 550–52. http://dx.doi.org/10.1177/030089160909500428.

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Adaptive radiation therapy (ART) is the next improvement in image-guided radiation therapy (IGRT). ART consists in changing treatment delivery to compensate for changes in patient anatomy or tumor volume. The treatment planning is therefore adapted to the new target volume. By daily imaging, the tumor volume can be assessed and compared with the initial volume. In case of tumor progression or tumor response, a new plan can be obtained to adequately treat the new volume. We report the use of ART with the Plan Adaptive software of TomoTherapy Inc. in a patient with massive breast cancer recurrence in the axilla. Between the CT simulation and the first day of radiotherapy the axillary lesion progressed. Megavolt CT performed to image-guide the treatment showed impressive growth of the lesion, which went out of the treatment field. By studying the dose distribution on the new anatomy, we found that the planning target volume was substantially undercovered by the prescription dose. Adaptive planning was performed using the anatomical information acquired by the megavolt CT.

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Seppenwoolde, Yvette, Katarina Majercakova, Martin Buschmann, Elke Dörr, Alina E. Sturdza, Maximilian P. Schmid, Richard Pötter, and Dietmar Georg. "Early morbidity and dose–volume effects in definitive radiochemotherapy for locally advanced cervical cancer: a prospective cohort study covering modern treatment techniques." Strahlentherapie und Onkologie 197, no. 6 (April 30, 2021): 505–19. http://dx.doi.org/10.1007/s00066-021-01781-6.

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Abstract Purpose Predicting morbidity for patients with locally advanced cervix cancer after external beam radiotherapy (EBRT) based on dose–volume parameters remains an unresolved issue in definitive radiochemotherapy. The aim of this prospective study was to correlate patient characteristics and dose–volume parameters to various early morbidity endpoints for different EBRT techniques, including volumetric modulated arc therapy (VMAT) and adaptive radiotherapy (ART). Methods and materials The study population consisted of 48 patients diagnosed with locally advanced cervix cancer, treated with definitive radiochemotherapy including image-guided adaptive brachytherapy (IGABT). Multiple questionnaires (CTCAE 4.03, QLQ-C30 and EORTC QLQ-CX24) were assessed prospectively for patients treated with different EBRT techniques, including online adaptive VMAT. Contouring and treatment planning was based on the EMBRACE protocols. Acute toxicity, classified as general, gastrointestinal (GI) or genitourinary (GU) and their corresponding dose–volume histograms (DVHs) were first correlated by applying least absolute shrinkage and selection operator (LASSO) and subsequently evaluated by multiple logistic binomial regression. Results The treated EBRT volumes varied for the different techniques with ~2500 cm3 for 3D conformal radiotherapy (3D-CRT), ~2000 cm3 for EMBRACE‑I VMAT, and ~1800 cm3 for EMBRACE-II VMAT and ART. In general, a worsening of symptoms during the first 5 treatment weeks and recovery afterwards was observed. Dose–volume parameters significantly correlating with stool urgency, rectal and urinary incontinence were as follows: bowel V40Gy < 250 cm3, rectum V40Gy < 80% and bladder V40Gy < 80–90%. Conclusion This prospective study demonstrated the impact of EBRT treatment techniques in combination with chemotherapy on early morbidity. Dose–volume effects for dysuria, urinary incontinence, stool urgency, diarrhea, rectal bleeding, rectal incontinence and weight loss were found.

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Albertini, Francesca, Michael Matter, Lena Nenoff, Ye Zhang, and Antony Lomax. "Online daily adaptive proton therapy." British Journal of Radiology 93, no. 1107 (March 2020): 20190594. http://dx.doi.org/10.1259/bjr.20190594.

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It is recognized that the use of a single plan calculated on an image acquired some time before the treatment is generally insufficient to accurately represent the daily dose to the target and to the organs at risk. This is particularly true for protons, due to the physical finite range. Although this characteristic enables the generation of steep dose gradients, which is essential for highly conformal radiotherapy, it also tightens the dependency of the delivered dose to the range accuracy. In particular, the use of an outdated patient anatomy is one of the most significant sources of range inaccuracy, thus affecting the quality of the planned dose distribution. A plan should be ideally adapted as soon as anatomical variations occur, ideally online. In this review, we describe in detail the different steps of the adaptive workflow and discuss the challenges and corresponding state-of-the art developments in particular for an online adaptive strategy.

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Cepeda-Trujillo, Lina Marcela, Jesús Miguel Mosquera-Aguirre, Daniela Yurani Rojas-Atehortua, and Alix Yaneth Perdomo-Romero. "Coping and adaptation of adults with cancer: the art of nursing care." Aquichan 22, no. 1 (January 26, 2022): 1–15. http://dx.doi.org/10.5294/aqui.2022.22.1.7.

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Objective: To determine the coping and adaptive capabilities in patients with cancer undergoing treatment. Methodology: This was a quantitative and descriptive cross-sectional study; the sample consisted of 100 patients with a cancer diagnosis who received chemotherapy and/or radiotherapy treatment between June and August 2019, meeting the inclusion criteria. The Coping and Adaptation Processing Scale (CAPS) was used. Results: 53 % of the patients participating in the study presented high coping and adaptive capabilities; 40 % presented medium capabilities, and 7 % presented low capabilities. Conclusion: Continuous follow-up is extremely important throughout the disease process; having a romantic partner becomes a protective factor since patients feel heard and cared for, which motivates them to follow through with the treatment. In the nursing field, knowing the experience of those who live with an illness allows for transcending and impacting care by providing holistic attention to patients.

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Das, J., B. Goswami, S. Goswami, K. J. Deka, G. Bora, and L. Das. "PO-1547 Dosimetric study of Adaptive radiotherapy (ART) for locally advanced head and neck cancer." Radiotherapy and Oncology 161 (August 2021): S1271—S1272. http://dx.doi.org/10.1016/s0167-8140(21)07998-6.

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Rachi, T., N. Nakamura, and R. V. Parshuram. "Evaluation of Metric Factors for Initiation of Adaptive Radiotherapy (ART) in Head and Neck IMRT." International Journal of Radiation Oncology*Biology*Physics 108, no. 3 (November 2020): e268. http://dx.doi.org/10.1016/j.ijrobp.2020.07.644.

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Li, Yang, Yoshiki Kubota, Mutsumi Tashiro, and Tatsuya Ohno. "Value of Three-Dimensional Imaging Systems for Image-Guided Carbon Ion Radiotherapy." Cancers 11, no. 3 (March 2, 2019): 297. http://dx.doi.org/10.3390/cancers11030297.

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Carbon ion radiotherapy (C-ion RT) allows excellent dose distribution because of the Bragg Peak. Compared with conventional radiotherapy, it delivers a higher dose with a smaller field. However, the dose distribution is sensitive to anatomical changes. Imaging technologies are necessary to reduce uncertainties during treatment, especially for hypofractionated and adaptive radiotherapy (ART). In-room computed tomography (CT) techniques, such as cone-beam CT (CBCT) and CT-on-rails are routinely used in photon centers and play a key role in improving treatment accuracy. For C-ion RT, there is an increasing demand for a three-dimensional (3D) image-guided system because of the limitations of the present two-dimensional (2D) imaging verification technology. This review discusses the current imaging system used in carbon ion centers and the potential benefits of a volumetric image-guided system.

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Lalondrelle, S., V. N. Hansen, H. McNair, R. Huddart, A. Horwich, D. Dearnaley, and V. Khoo. "One Size Doesn't Fit All: The Value of Adaptive Radiotherapy (ART) Planning Methods using Daily Image Guidance in Bladder Radiotherapy (RT)." International Journal of Radiation Oncology*Biology*Physics 72, no. 1 (September 2008): S325. http://dx.doi.org/10.1016/j.ijrobp.2008.06.1111.

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Karaca, Sibel. "Effect of Changing Phantom Thickness on Helical Radiotherapy Plan: Dosimetric Analysis." Polish Journal of Medical Physics and Engineering 25, no. 2 (June 1, 2019): 121–26. http://dx.doi.org/10.2478/pjmpe-2019-0016.

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Abstract Purpose: The aim of this study is to investigate the effect of changing phantom thickness on high dose region of interest (HD_ROI) and low dose ROI’s (LW_ROI’s) doses during helical radiotherapy (RT) by utilizing Adaptive RT (ART) technique. Materials and Methods: The cylindrical phantom (CP) is wrapped with different thickness boluses and scanned in the kilovoltage computed tomography (KVCT). HD_ROI and LW_ROI’s were created in contouring system and nine same plans (1.8 Gy/Fr) were made with images of different thicknesses CP. The point dose measurements were performed using ionization chamber in Helical Tomotherapy (HT) treatment machine. For detecting thickness reduction effect, CP was irradiated using bolus-designed plans and it was irradiated using without bolus plan. The opposite of this scenario was applied to determine the thickness increase. KVCT and megavoltage CT (MVCT) images were used for dose comparison. The HT Planned Adaptive Software was used to see the differences in the planning and verification doses at dose volume histograms (DVH). Results: Point dose measurements showed a 4.480% dose increase in 0.5 cm depth reduction for HD_ROI. These differences reached 8.508% in 2 cm depth and 15,279% in 5 cm depth. At the same time, a dose reduction of 0.665% was determined for a 0.5cm depth increase, a dose reduction of 1.771% was determined for a 2 cm depth increase, a dose reduction of 5.202% was determined for a 5 cm depth increase for the HD_ROI. The ART plan results show that the dose changes in the HD_ROI was greater than the LW_ROI’s. Conclusion: Phantom thicknesses change can lead to a serious dose increase or decrease in the HD_ROI and LW_ROI’s.

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Stowe, H. B., A. Price, L. E. Henke, E. Laugeman, C. G. Robinson, O. L. Green, Y. Hao, et al. "CT-Guided Adaptive Radiotherapy (CT-ART) Improves Target Coverage in Hypofractionated Radiation Therapy for Bladder Cancer." International Journal of Radiation Oncology*Biology*Physics 114, no. 3 (November 2022): e206. http://dx.doi.org/10.1016/j.ijrobp.2022.07.1133.

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Jo, Yoon Young, Ji Woon Yea, Jaehyeon Park, Se An Oh, and Jae Won Park. "Optimized Adaptive Radiotherapy with Individualized Plan Library for Muscle-Invasive Bladder Cancer Using Internal Target Volume Generation." Cancers 14, no. 19 (September 26, 2022): 4674. http://dx.doi.org/10.3390/cancers14194674.

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The bladder is subject to filling variation, which poses a challenge to radiotherapy (RT) delivery. We aimed to assess feasibility and clinical outcomes in patients with bladder cancer treated with adaptive RT (ART) using individualized plan libraries. We retrospectively analyzed 19 patients who underwent RT for muscle-invasive bladder cancer (MIBC) in 2015–2021. Four planning computed tomography (CT) scans were acquired at 15-min intervals, and a library of three intensity-modulated RT plans were generated using internal target volumes (ITVs). A post-treatment cone-beam CT (CBCT) scan was acquired daily to assess intra-fraction filling and coverage. All patients completed the treatment, with 408 post-treatment CBCT scans. The bladder was out of the planning target volume (PTV) range in 12 scans. The volumes of the evaluated PTV plans were significantly smaller than those of conventional PTV. The 1-year and 2-year overall survival rates were 88.2% and 63.7%, respectively. Of eight cases that experienced recurrence, only two developed MIBC. There were no grade 3 or higher RT-related adverse events. ART using plan libraries and ITVs demonstrated good survival outcomes with a high local control rate. Irradiated normal tissue volume and treatment margins may be reduced through this approach, potentially resulting in lower toxicity rates.

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McNair, H. A., T. Wiseman, E. Joyce, B. Peet, and R. A. Huddart. "International survey; current practice in On-line adaptive radiotherapy (ART) delivered using Magnetic Resonance Image (MRI) guidance." Technical Innovations & Patient Support in Radiation Oncology 16 (December 2020): 1–9. http://dx.doi.org/10.1016/j.tipsro.2020.08.002.

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Brabbins, D., A. Martinez, D. Yan, M. Wallace, D. Lockman, F. Vicini, and J. Wong. "A dose selection-escalation trial using the adaptive radiotherapy process (ART) in localized prostate adenocarcinoma: acute toxicity." International Journal of Radiation Oncology*Biology*Physics 51, no. 3 (November 2001): 276–77. http://dx.doi.org/10.1016/s0360-3016(01)02331-8.

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Kim, T., K. Kiser, E. Laugeman, A. Price, H. M. Gach, N. Knutson, G. D. Hugo, et al. "Surface Imaging-Guided Adaptive Radiotherapy (ART): Imaging Protocol and Verification for Inter- and Intra-Fractional Motion Managements." International Journal of Radiation Oncology*Biology*Physics 114, no. 3 (November 2022): e193-e194. http://dx.doi.org/10.1016/j.ijrobp.2022.07.1107.

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Lam, Sai-Kit, Jiang Zhang, Yuan-Peng Zhang, Bing Li, Rui-Yan Ni, Ta Zhou, Tao Peng, et al. "A Multi-Center Study of CT-Based Neck Nodal Radiomics for Predicting an Adaptive Radiotherapy Trigger of Ill-Fitted Thermoplastic Masks in Patients with Nasopharyngeal Carcinoma." Life 12, no. 2 (February 6, 2022): 241. http://dx.doi.org/10.3390/life12020241.

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Significant lymph node shrinkage is common in patients with nasopharyngeal carcinoma (NPC) throughout radiotherapy (RT) treatment, causing ill-fitted thermoplastic masks (IfTMs). To deal with this, an ad hoc adaptive radiotherapy (ART) may be required to ensure accurate and safe radiation delivery and to maintain treatment efficacy. Presently, the entire procedure for evaluating an eligible ART candidate is time-consuming, resource-demanding, and highly inefficient. In the artificial intelligence paradigm, the pre-treatment identification of NPC patients at risk for IfTMs has become greatly demanding for achieving efficient ART eligibility screening, while no relevant studies have been reported. Hence, we aimed to investigate the capability of computed tomography (CT)-based neck nodal radiomics for predicting IfTM-triggered ART events in NPC patients via a multi-center setting. Contrast-enhanced CT and the clinical data of 124 and 58 NPC patients from Queen Elizabeth Hospital (QEH) and Queen Mary Hospital (QMH), respectively, were retrospectively analyzed. Radiomic (R), clinical (C), and combined (RC) models were developed using the ridge algorithm in the QEH cohort and evaluated in the QMH cohort using the median area under the receiver operating characteristics curve (AUC). Delong’s test was employed for model comparison. Model performance was further assessed on 1000 replicates in both cohorts separately via bootstrapping. The R model yielded the highest “corrected” AUC of 0.784 (BCa 95%CI: 0.673–0.859) and 0.723 (BCa 95%CI: 0.534–0.859) in the QEH and QMH cohort following bootstrapping, respectively. Delong’s test indicated that the R model performed significantly better than the C model in the QMH cohort (p < 0.0001), while demonstrating no significant difference compared to the RC model (p = 0.5773). To conclude, CT-based neck nodal radiomics was capable of predicting IfTM-triggered ART events in NPC patients in this multi-center study, outperforming the traditional clinical model. The findings of this study provide valuable insights for future study into developing an effective screening strategy for ART eligibility in NPC patients in the long run, ultimately alleviating the workload of clinical practitioners, streamlining ART procedural efficiency in clinics, and achieving personalized RT for NPC patients in the future.

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Hamming-Vrieze, Olga, Simon van Kranen, Iris Walraven, Arash Navran, Abrahim Al-Mamgani, Margot Tesselaar, Michiel van den Brekel, and Jan-Jakob Sonke. "Deterioration of Intended Target Volume Radiation Dose Due to Anatomical Changes in Patients with Head-and-Neck Cancer." Cancers 13, no. 17 (August 24, 2021): 4253. http://dx.doi.org/10.3390/cancers13174253.

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Delivered radiation dose can differ from intended dose. This study quantifies dose deterioration in targets, identifies predictive factors, and compares dosimetric to clinical patient selection for adaptive radiotherapy in head-and-neck cancer patients. One hundred and eighty-eight consecutive head-and-neck cancer patients treated up to 70 Gy were analyzed. Daily delivered dose was calculated, accumulated, and compared to the planned dose. Cutoff values (1 Gy/2 Gy) were used to assess plan deterioration in the highest/lowest dose percentile (D1/D99). Differences in clinical factors between patients with/without dosimetric deterioration were statistically tested. Dosimetric deterioration was evaluated in clinically selected patients for adaptive radiotherapy with CBCT. Respectively, 16% and 4% of patients had deterioration over 1 Gy in D99 and D1 in any of the targets, this was 5% (D99) and 2% (D1) over 2 Gy. Factors associated with deterioration of D99 were higher baseline weight/BMI, weight gain early in treatment, and smaller PTV margins. The sensitivity of visual patient selection with CBCT was 22% for detection of dosimetric changes over 1 Gy. Large dose deteriorations in targets occur in a minority of patients. Clinical prediction based on patient characteristics or CBCT is challenging and dosimetric selection tools seem warranted to identify patients in need for ART, especially in treatment with small PTV margins.

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Xu, Zijie, Ronald Chen, Andrew Wang, Andrea Kress, Mark Foskey, An Qin, Timothy Cullip, et al. "Comparison of User-Directed and Automatic Mapping of the Planned Isocenter to Treatment Space for Prostate IGRT." International Journal of Biomedical Imaging 2013 (2013): 1–12. http://dx.doi.org/10.1155/2013/892152.

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Image-guided radiotherapy (IGRT), adaptive radiotherapy (ART), and online reoptimization rely on accurate mapping of the radiation beam isocenter(s) from planning to treatment space. This mapping involves rigid and/or nonrigid registration of planning (pCT) and intratreatment (tCT) CT images. The purpose of this study was to retrospectively compare a fully automatic approach, including a non-rigid step, against a user-directed rigid method implemented in a clinical IGRT protocol for prostate cancer. Isocenters resulting from automatic and clinical mappings were compared to reference isocenters carefully determined in each tCT. Comparison was based on displacements from the reference isocenters and prostate dose-volume histograms (DVHs). Ten patients with a total of 243 tCTs were investigated. Fully automatic registration was found to be as accurate as the clinical protocol but more precise for all patients. The average of the unsignedx, y,andzoffsets and the standard deviations (σ) of the signed offsets computed over all images were (avg. ± σ (mm)): 1.1 ± 1.4, 1.8 ± 2.3, 2.5 ± 3.5 for the clinical protocol and 0.6 ± 0.8, 1.1 ± 1.5 and 1.1 ± 1.4 for the automatic method. No failures or outliers from automatic mapping were observed, while 8 outliers occurred for the clinical protocol.

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Nestle, U., S. Kremp, D. Hellwig, A. Grgic, H. G. Buchholz, W. Mischke, C. Gromoll, et al. "Multi-centre calibration of an adaptive thresholding method for PET-based delineation of tumour volumes in radiotherapy planning of lung cancer." Nuklearmedizin 51, no. 03 (2012): 101–10. http://dx.doi.org/10.3413/nukmed-0452-11-12.

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SummaryPurpose: To evaluate the calibration of an adaptive thresholding algorithm (contrastoriented algorithm) for FDG PET-based delineation of tumour volumes in eleven centres with respect to scanner types and image data processing by phantom measurements. Methods: A cylindrical phantom with spheres of different diameters was filled with FDG realizing different signal-to-background ratios and scanned using 5 Siemens Biograph PET/CT scanners, 5 Philips Gemini PET/CT scanners, and one Siemens ECAT-ART PET scanner. All scans were analysed by the contrast-oriented algorithm implemented in two different software packages. For each site, the threshold SUVs of all spheres best matching the known sphere volumes were determined. Calibration parameters a and b were calculated for each combination of scanner and image-analysis software package. In addition, “scanner-typespecific” calibration curves were determined from all values obtained for each combination of scanner type and software package. Both kinds of calibration curves were used for volume delineation of the spheres. Results: Only minor differences in calibration parameters were observed for scanners of the same type (Δa ≤ 4%, Δb ≤ 14%) provided that identical imaging protocols were used whereas significant differences were found comparing calibration parameters of the ART scanner with those of scanners of different type (Δa ≤ 60%, Δb ≤ 54%). After calibration, for all scanners investigated the calculated SUV thresholds for auto-contouring did not differ significantly (all p > 0.58). The resulting sphere volumes deviated by less than –7% to +8% from the true values. Conclusion: After multi-centre calibration the use of the contrast-oriented algorithm for FDG PET-based delineation of tumour volumes in the different centres using different scanner types and specific imaging protocols is feasible.

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Muelas-Soria, Rodrigo, Rafael García-Mollá, Virginia Morillo-Macías, Jorge Bonaque-Alandí, Patricia Sorribes-Carreras, Francisco García-Piñón, and Carlos Ferrer-Albiach. "The Usefulness of Adaptative Radiotherapy in Prostate Cancer: How, When, and Who?" Biomedicines 10, no. 6 (June 13, 2022): 1401. http://dx.doi.org/10.3390/biomedicines10061401.

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The aim of this study was to develop a deformable image registration (DIR)-based offline ART protocol capable of identifying significant dosimetric changes in the first treatment fractions to determine when adaptive replanning is needed. A total of 240 images (24 planning CT (pCT) and 216 kilovoltage cone-beam CT (CBCT)) were prospectively acquired from 24 patients with prostate adenocarcinoma during the first three weeks of their treatment (76 Gy in 38 fractions). This set of images was used to plan a hypofractionated virtual treatment (57.3 Gy in 15 fractions); correlation with the DIR of pCT and each CBCT allowed to translate planned doses to each CBCT, and finally mapped back to the pCT to compare with those actually administered. In 37.5% of patients, doses administered in 50% of the rectum (D50) would have exceeded the dose limitation to 50% of the rectum (R50). We first observed a significant variation of the planned rectal volume in the CBCTs of fractions 1, 3, and 5. Then, we found a significant relationship between the D50 accumulated in fractions 1, 3, and 5 and the lack of compliance with the R50. Finally, we found that a D50 variation rate [100 × (administered D50 − planned D50/planned D50)] > 1% in fraction three can reliably identify variations in administered doses that will lead to exceeding rectal dose constraint.

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Grégoire, V. "Multi-modal imaging for dose planning and its benefits: the paradigm of head and neck tumours." Annals of the ICRP 47, no. 3-4 (April 13, 2018): 159. http://dx.doi.org/10.1177/0146645318756250.

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The ultimate goal of any radiotherapy is to eradicate the disease without inflicting damage on the normal tissues surrounding the tumours, which could be responsible for late treatment morbidity. To achieve this objective, the first step is to precisely select and delineate the target volumes to which a given dose will be prescribed. This step requires the use of multi-modal images from clinical examination to anatomical and molecular images. Imaging examination will be used not only to delineate the boundaries of the tumour volume, but also to assess tumour heterogeneity and, possibly, to guide a heterogeneous dose prescription (i.e. the so-called ‘dose painting’ approach). Last, re-imaging the patient during treatment to assess variation of the tumour volume during radiotherapy may also be performed in the framework of adaptive treatment. Over the last decade, a lot of information has been gathered on the use of multi-modal imaging for dose planning, and its potential and technical difficulties have been identified. During the lecture, the speaker will review the state-of-the-art of multi-imaging for treatment, using head and neck tumours as a paradigm, emphasising what should be considered as routine practice and what should still be viewed as research questions. © 2018 ICRP. Published by SAGE.

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Rigaud, Bastien, Antoine Simon, Joël Castelli, Maxime Gobeli, Juan-David Ospina Arango, Guillaume Cazoulat, Olivier Henry, Pascal Haigron, and Renaud De Crevoisier. "Evaluation of Deformable Image Registration Methods for Dose Monitoring in Head and Neck Radiotherapy." BioMed Research International 2015 (2015): 1–16. http://dx.doi.org/10.1155/2015/726268.

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In the context of head and neck cancer (HNC) adaptive radiation therapy (ART), the two purposes of the study were to compare the performance of multiple deformable image registration (DIR) methods and to quantify their impact for dose accumulation, in healthy structures. Fifteen HNC patients had a planning computed tomography (CT0) and weekly CTs during the 7 weeks of intensity-modulated radiation therapy (IMRT). Ten DIR approaches using different registration methods (demons or B-spline free form deformation (FFD)), preprocessing, and similarity metrics were tested. Two observers identified 14 landmarks (LM) on each CT-scan to compute LM registration error. The cumulated doses estimated by each method were compared. The two most effective DIR methods were the demons and the FFD, with both the mutual information (MI) metric and the filtered CTs. The corresponding LM registration accuracy (precision) was 2.44 mm (1.30 mm) and 2.54 mm (1.33 mm), respectively. The corresponding LM estimated cumulated dose accuracy (dose precision) was 0.85 Gy (0.93 Gy) and 0.88 Gy (0.95 Gy), respectively. The mean uncertainty (difference between maximal and minimal dose considering all the 10 methods) to estimate the cumulated mean dose to the parotid gland (PG) was 4.03 Gy (SD = 2.27 Gy, range: 1.06–8.91 Gy).

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Siker, M. L., W. A. Tome, and M. P. Mehta. "Tumor volume changes on serial imaging with megavoltage CT for non-small cell lung cancer during conformal radiotherapy." Journal of Clinical Oncology 24, no. 18_suppl (June 20, 2006): 17041. http://dx.doi.org/10.1200/jco.2006.24.18_suppl.17041.

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17041 Background: Adaptive radiotherapy allows treatment plan modification based on data obtained during treatment. Assessing volume changes during treatment is now possible with intra-treatment imaging capabilities on radiotherapy devices. This study assesses non-small cell lung cancer (NSCLC) volume changes during treatment with conformal intensity-modulated radiotherapy by evaluating serial megavoltage CT (MVCT) scans. Methods: MVCTs were retrospectively reviewed for 25 patients treated with the TomoTherapy Hi-Art system at the University of Wisconsin. Twenty-one patients received definitive radiotherapy, 4 with extracranial stereotactic radioablation (60 Gy in 5 fractions) and 17 on a dose-per-fraction escalation protocol (57–80.5 Gy in 25 fractions). Four patients were treated palliatively (22–30 Gy in 8–10 fractions). Gross tumor volumes (GTVs) were contoured on serial MVCTs at weekly intervals, by individuals other than the treating physician, to minimize bias. Each patient had 3–25 scans including one at the beginning, mid-way, and one at the end of treatment. Initial GTVs ranged from 1.4 - 565.5 cm3 (mean = 70 cm3). Results: At completion of treatment, no patient demonstrated a complete response (CR). Partial response (PR) defined as a >65% decrease in tumor volume occurred in 3 (12%) and marginal response (MR) defined as a 35 - 65% reduction in tumor volume was noted in 5 (20%). The remaining 17 patients (68%) showed stable disease (SD) defined as <35% reduction or <40% increase in size. The minimum “scorable threshold” for volume discrepancy between scans to account for inter-scan assessment variability was set at >25% volume change; 10 patients (40%) had >25% tumor regression. None of the patients treated ablatively or palliatively showed tumor regression during treatment. Conclusions: Although gross tumor regression during treatment may be objectively measured using MVCTs, substantial volumetric decrease occurs only in a minority. The clinical significance of this regression is questionable, as there is no way to document histologic tumor clearance and therefore field reductions during radiotherapy cannot be recommended. [Table: see text]

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Borella, Fulvio, Mario Preti, Luca Bertero, Giammarco Collemi, Isabella Castellano, Paola Cassoni, Stefano Cosma, et al. "Is There a Place for Immune Checkpoint Inhibitors in Vulvar Neoplasms? A State of the Art Review." International Journal of Molecular Sciences 22, no. 1 (December 27, 2020): 190. http://dx.doi.org/10.3390/ijms22010190.

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Vulvar cancer (VC) is a rare neoplasm, usually arising in postmenopausal women, although human papilloma virus (HPV)-associated VC usually develop in younger women. Incidences of VCs are rising in many countries. Surgery is the cornerstone of early-stage VC management, whereas therapies for advanced VC are multimodal and not standardized, combining chemotherapy and radiotherapy to avoid exenterative surgery. Randomized controlled trials (RCTs) are scarce due to the rarity of the disease and prognosis has not improved. Hence, new therapies are needed to improve the outcomes of these patients. In recent years, improved knowledge regarding the crosstalk between neoplastic and tumor cells has allowed researchers to develop a novel therapeutic approach exploiting these molecular interactions. Both the innate and adaptive immune systems play a key role in anti-tumor immunesurveillance. Immune checkpoint inhibitors (ICIs) have demonstrated efficacy in multiple tumor types, improving survival rates and disease outcomes. In some gynecologic cancers (e.g., cervical cancer), many studies are showing promising results and a growing interest is emerging about the potential use of ICIs in VC. The aim of this manuscript is to summarize the latest developments in the field of VC immunoncology, to present the role of state-of-the-art ICIs in VC management and to discuss new potential immunotherapeutic approaches.

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Guibert, G., C. Tamburella, and P. Weber. "75 Implementation and evaluation of offline adaptive radiotherapy (ART) based on pelvic CBCT (XVI-Elekta) with Dynamic Planning (DP) module of pinnacle 16.2." Physica Medica 68 (December 2019): 46. http://dx.doi.org/10.1016/j.ejmp.2019.09.156.

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Bąk, Bartosz, Agnieszka Skrobała, Anna Adamska, Natalia Józefacka, Sara Styś, and Julian Malicki. "Evaluation and risk factors of volume and dose differences of selected structures in patients with head and neck cancer treated on Helical TomoTherapy by using Deformable Image Registration tool." Polish Journal of Medical Physics and Engineering 28, no. 2 (May 6, 2022): 60–68. http://dx.doi.org/10.2478/pjmpe-2022-0007.

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Abstract Introduction: The aim of this study was the evaluation of volume and dose differences in selected structures in patients with head and neck cancer during treatment on Helical TomoTherapy (HT) using a commercially available deformable image registration (DIR) tool. We attempted to identify anatomical and clinical predictive factors for significant volume changes probability. Material and methods: According to our institutional protocol, we retrospectively evaluated the group of 20 H&N cancer patients treated with HT who received Adaptive Radiotherapy (ART) due to soft tissue alterations spotted on daily MVCT. We compared volumes on initial computed tomography (iCT) and replanning computed tomography (rCT) for clinical target volumes (CTV) – CTV1 (the primary tumor) and CTV2 (metastatic lymph nodes), parotid glands (PG) and body contour (B-body). To estimate the planned and delivered dose discrepancy, the dose from the original plan was registered and deformed to create a simulation of dose distribution on rCT (DIR-rCT). Results: The decision to replan was made at the 4th week of RT (N = 6; 30%). The average volume reduction in parotid right PG[R] and left PG[L] was 4.37 cc (18.9%) (p < 0.001) and 3.77 cc (16.8%) (p = 0.004), respectively. In N = 13/20 cases, the delivered dose was greater than the planned dose for PG[R] of mean 3 Gy (p < 0.001), and in N = 6/20 patients for PG[L] the mean of 3.6 Gy (p = 0.031). Multivariate regression analysis showed a very strong predictor explaining 88% (R2 = 0.88) and 83% (R2 = 0.83) of the variance based on the mean dose of iPG[R] and iPG[L] (p < 0.001), respectively. No statistically significant correlation between volume changes and risk factors was found. Conclusions: Dosimetric changes to the target demonstrated the validity of replanning. A DIR tool can be successfully used for dose deformation and ART qualification, significantly reducing the workload of radiotherapy centers. In addition, the mean dose for PG was a significant predictor that may indicate the need for a replan.

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Lee, C., and C. Lee. "SU-E-J-179: Assessment of Tumor Volume Change and Movement During Stereotactic Body Radiotherapy (SBRT) for Lung Cancer: Is Adaptive Radiation Therapy (ART) Necessary?" Medical Physics 42, no. 6Part10 (June 2015): 3306. http://dx.doi.org/10.1118/1.4924264.

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Vu, N. "The Changes in Tumor Volume and Location During Stereotactic Body Radiotherapy (SBRT) Period in Patients with Stage I Non-Small Cell Lung Cancer (NSCLC): The Need for Implementation of the Adaptive Radiotherapy (ART) Planning." International Journal of Radiation Oncology*Biology*Physics 108, no. 3 (November 2020): e150. http://dx.doi.org/10.1016/j.ijrobp.2020.07.1321.

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Liu, Yuxiang, Xinyuan Chen, Ji Zhu, Bining Yang, Ran Wei, Rui Xiong, Hong Quan, Yueping Liu, Jianrong Dai, and Kuo Men. "A two-step method to improve image quality of CBCT with phantom-based supervised and patient-based unsupervised learning strategies." Physics in Medicine & Biology 67, no. 8 (April 11, 2022): 084001. http://dx.doi.org/10.1088/1361-6560/ac6289.

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Abstract Objective. In this study, we aimed to develop deep learning framework to improve cone-beam computed tomography (CBCT) image quality for adaptive radiation therapy (ART) applications. Approach. Paired CBCT and planning CT images of 2 pelvic phantoms and 91 patients (15 patients for testing) diagnosed with prostate cancer were included in this study. First, well-matched images of rigid phantoms were used to train a U-net, which is the supervised learning strategy to reduce serious artifacts. Second, the phantom-trained U-net generated intermediate CT images from the patient CBCT images. Finally, a cycle-consistent generative adversarial network (CycleGAN) was trained with intermediate CT images and deformed planning CT images, which is the unsupervised learning strategy to learn the style of the patient images for further improvement. When testing or applying the trained model on patient CBCT images, the intermediate CT images were generated from the original CBCT image by U-net, and then the synthetic CT images were generated by the generator of CycleGAN with intermediate CT images as input. The performance was compared with conventional methods (U-net/CycleGAN alone trained with patient images) on the test set. Results. The proposed two-step method effectively improved the CBCT image quality to the level of CT scans. It outperformed conventional methods for region-of-interest contouring and HU calibration, which are important to ART applications. Compared with the U-net alone, it maintained the structure of CBCT. Compared with CycleGAN alone, our method improved the accuracy of CT number and effectively reduced the artifacts, making it more helpful for identifying the clinical target volume. Significance. This novel two-step method improves CBCT image quality by combining phantom-based supervised and patient-based unsupervised learning strategies. It has immense potential to be integrated into the ART workflow to improve radiotherapy accuracy.

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Morenc, A., K. A. Johnson, T. Sridhar, S. I. Ahmed, and L. Aznar-Garcia. "124 Dosimetric evaluation of adaptive planning during radiotherapy (ART) in radical lung to ensure tumour coverage and/or minimise doses to organs at risk – case discussion." Lung Cancer 91 (January 2016): S45. http://dx.doi.org/10.1016/s0169-5002(16)30141-6.

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Lim, Seng Boh, Nancy Lee, Kaveh Zakeri, Peter Greer, Todsaporn Fuangrod, Frederick Coffman, Laura Cerviño, and D. Michael Lovelock. "Can the Risk of Dysphagia in Head and Neck Radiation Therapy Be Predicted by an Automated Transit Fluence Monitoring Process During Treatment? A First Comparative Study of Patient Reported Quality of Life and the Fluence-Based Decision Support Metric." Technology in Cancer Research & Treatment 20 (January 1, 2021): 153303382110279. http://dx.doi.org/10.1177/15330338211027906.

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Purpose/Objective(s): The additional personnel and imaging procedures required for Adaptive Radiation Therapy (ART) pose a challenge for a broad implementation. We hypothesize that a change in transit fluence during the treatment course is correlated with the change of quality of life and thus can be used as a replanning trigger. Materials/Methods: Twenty-one head and neck cancer (HNC) patients filled out an MD Anderson Dysphagia Inventory (MDADI) questionnaire, before-and-after the radiotherapy treatment course. The transit fluence was measured by the Watchdog (WD) in-vivo portal dosimetry system. The patients were monitored with daily WD and weekly CBCTs. The region of interest (ROI) of each patient was defined as the outer contour of the patient between approximate spine levels C1 to C4, essentially the neck and mandible inside the beam’s eye view. The nth day integrated transit fluence change, Δϕn, and the volume change, ΔVROI, of the ROI of each patient was calculated from the corresponding WD and CBCT measurements. The correlation between MDADI scores and age, gender, planning mean dose to salivary glands <Dsg>, weight change ΔW, ΔVROI, and Δϕn, were analyzed using the ranked-Pearson correlation. Results: No statistically significant correlation was found for age, gender and ΔW. <Dsg> was found to have clinically important correlation with functional MDADI (ρ = −0.39, P = 0.081). ΔVROI was found to have statistically significant correlation of 0.44, 0.47 and 0.44 with global, physical and functional MDADI ( P-value < 0.05). Δϕn was found to have statistically significant ranked-correlation (−0.46, −0.46 and −0.45) with physical, functional and total MDADI ( P-value < 0.05). Conclusion: A transit fluence based decision support metric (DSM) is statistically correlated with the dysphagia risk. It can not only be used as an early signal in assisting clinicians in the ART patient selection for replanning, but also lowers the resource barrier of ART implementation.

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Harsolia, A. R., G. Hugo, L. Kestin, C. Vargas, A. Martinez, and D. Yan. "A Dosimetric Comparison of Multiple 4D Planning Techniques to 3D Conformal Plans for Lung Tumors: Substantial Improvement with Image-Guided Adaptive Radiotherapy (IG-ART) Utilizing Online Cone Beam CT." International Journal of Radiation Oncology*Biology*Physics 63 (October 2005): S28—S29. http://dx.doi.org/10.1016/j.ijrobp.2005.07.056.

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Sager, Omer, Ferrat Dincoglan, Bora Uysal, Selcuk Demiral, Hakan Gamsiz, Yelda Elcim, Esin Gundem, Bahar Dirican, and Murat Beyzadeoglu. "Evaluation of adaptive radiotherapy (ART) by use of replanning the tumor bed boost with repeated computed tomography (CT) simulation after whole breast irradiation (WBI) for breast cancer patients having clinically evident seroma." Japanese Journal of Radiology 36, no. 6 (April 5, 2018): 401–6. http://dx.doi.org/10.1007/s11604-018-0735-2.

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Keall, Paul, Per Poulsen, and Jeremy T. Booth. "See, Think, and Act: Real-Time Adaptive Radiotherapy." Seminars in Radiation Oncology 29, no. 3 (July 2019): 228–35. http://dx.doi.org/10.1016/j.semradonc.2019.02.005.

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van Son, Marieke, Max Peters, Marinus Moerland, Linda Kerkmeijer, Jan Lagendijk, and Jochem van der Voort van Zyp. "Focal Salvage Treatment of Radiorecurrent Prostate Cancer: A Narrative Review of Current Strategies and Future Perspectives." Cancers 10, no. 12 (December 3, 2018): 480. http://dx.doi.org/10.3390/cancers10120480.

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Over the last decades, primary prostate cancer radiotherapy saw improving developments, such as more conformal dose administration and hypofractionated treatment regimens. Still, prostate cancer recurrences after whole-gland radiotherapy remain common, especially in patients with intermediate- to high-risk disease. The vast majority of these patients are treated palliatively with androgen deprivation therapy (ADT), which exposes them to harmful side-effects and is only effective for a limited amount of time. For patients with a localized recurrent tumor and no signs of metastatic disease, local treatment with curative intent seems more rational. However, whole-gland salvage treatments such as salvage radiotherapy or salvage prostatectomy are associated with significant toxicity and are, therefore, uncommonly performed. Treatments that are solely aimed at the recurrent tumor itself, thereby better sparing the surrounding organs at risk, potentially provide a safer salvage treatment option in terms of toxicity. To achieve such tumor-targeted treatment, imaging developments have made it possible to better exclude metastatic disease and accurately discriminate the tumor. Currently, focal salvage treatment is being performed with different modalities, including brachytherapy, cryotherapy, high-intensity focused ultrasound (HIFU), and stereotactic body radiation therapy (SBRT). Oncologic outcomes seem comparable to whole-gland salvage series, but with much lower toxicity rates. In terms of oncologic control, these results will improve further with better understanding of patient selection. Other developments, such as high-field diagnostic MRI and live adaptive MRI-guided radiotherapy, will further improve precision of the treatment.

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Li, Bo, Jing Xue, Kaijian Xia, Leyuan Zhou, Pengjiang Qian, and Yizhang Jiang. "An Auto-Contouring Method for Kidney Using a Novel Semi-Supervised Leaning Extreme Learning Machine Method." Journal of Medical Imaging and Health Informatics 11, no. 8 (August 1, 2021): 2267–73. http://dx.doi.org/10.1166/jmihi.2021.3675.

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Background: Adaptive radiation therapy planning requires contour segmentation of dangerous organs in medical images. However, manual contour rendering is the most time-consuming and laborious work in radiotherap planning. In order to solve this problem, we propose a novel semi-supervised leaning extreme learning machine (SSL-ELM) method to realize abdominal Magnetic Resonance Imaging (MRI) guided Adaptive Radiation Therapy (MR-ART) automatic contour rendering. Method/Material: Our algorithm is based on the assumption that data within the same class are close to each other. We use this heuristic method to improve the ELM algorithm. The experimental results show that our proposed method outperforms existing classification algorithms. We used a data set of eight patients with unresectable abdominal malignant tumors recruited by professionals approved by the Cleveland Medical Center Institution Review Board. Each group included MRI and airborne T1MRI with randomly selected treatment phases. Each MRI consisted of 16 slices with a resolution of 370×370 pixels. Manual and automatic contours of the kidney were compared using Dice similarity index (DSI). Results: The proposed SSL-ELM algorithm has better performance than most classification algorithms, and the experimental results also show that the DSI values are above 0.87, with some samples reaching 0.99.

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Poon, Darren M. C., Jing Yuan, Bin Yang, Oi-Lei Wong, Sin-Ting Chiu, George Chiu, Kin-Yin Cheung, Siu-Ki Yu, and Raymond W. H. Yung. "A Prospective Study of Stereotactic Body Radiotherapy (SBRT) with Concomitant Whole-Pelvic Radiotherapy (WPRT) for High-Risk Localized Prostate Cancer Patients Using 1.5 Tesla Magnetic Resonance Guidance: The Preliminary Clinical Outcome." Cancers 14, no. 14 (July 18, 2022): 3484. http://dx.doi.org/10.3390/cancers14143484.

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Background: Conventionally fractionated whole-pelvic nodal radiotherapy (WPRT) improves clinical outcome compared to prostate-only RT in high-risk prostate cancer (HR-PC). MR-guided stereotactic body radiotherapy (MRgSBRT) with concomitant WPRT represents a novel radiotherapy (RT) paradigm for HR-PC, potentially improving online image guidance and clinical outcomes. This study aims to report the preliminary clinical experiences and treatment outcome of 1.5 Tesla adaptive MRgSBRT with concomitant WPRT in HR-PC patients. Materials and methods: Forty-two consecutive HR-PC patients (72.5 ± 6.8 years) were prospectively enrolled, treated by online adaptive MRgSBRT (8 Gy(prostate)/5 Gy(WPRT) × 5 fractions) combined with androgen deprivation therapy (ADT) and followed up (median: 251 days, range: 20–609 days). Clinical outcomes were measured by gastrointestinal (GI) and genitourinary (GU) toxicities according to the Common Terminology Criteria for Adverse Events (CTCAE) Scale v. 5.0, patient-reported quality of life (QoL) with EPIC (Expanded Prostate Cancer Index Composite) questionnaire, and prostate-specific antigen (PSA) responses. Results: All MRgSBRT fractions achieved planning objectives and dose specifications of the targets and organs at risk, and they were successfully delivered. The maximum cumulative acute GI/GU grade 1 and 2 toxicity rates were 19.0%/81.0% and 2.4%/7.1%, respectively. The subacute (>30 days) GI/GU grade 1 and 2 toxicity rates were 21.4%/64.3% and 2.4%/2.4%, respectively. No grade 3 toxicities were reported. QoL showed insignificant changes in urinary, bowel, sexual, and hormonal domain scores during the follow-up period. All patients had early post-MRgSBRT biochemical responses, while biochemical recurrence (PSA nadir + 2 ng/mL) occurred in one patient at month 18. Conclusions: To our knowledge, this is the first prospective study that showed the clinical outcomes of MRgSBRT with concomitant WPRT in HR-PC patients. The early results suggested favorable treatment-related toxicities and encouraging patient-reported QoLs, but long-term follow-up is needed to confirm our early results.

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Shah, C., L. L. Kestin, M. Ghilezan, F. A. Vicini, G. S. Gustafson, D. Brabbins, M. Wallace, K. Marvin, H. Ye, and A. Martinez. "A matched-pair analysis of dose-escalated adaptive image-guided radiotherapy (IGRT) versus pelvic irradiation with brachytherapy boost for intermediate- and high-risk prostate cancer." Journal of Clinical Oncology 29, no. 7_suppl (March 1, 2011): 71. http://dx.doi.org/10.1200/jco.2011.29.7_suppl.71.

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71 Background: The purpose of this study was to compare clinical outcomes in a cohort of intermediate- and high-risk prostate cancer patients treated with either dose-escalated adaptive IGRT or pelvic external beam RT with high-dose rate brachytherapy boost (EBRT+HDR). Methods: 1,520 patients with clinical stage T1-T3 N0 M0 prostate cancer were treated with either CT-based offline adaptive IGRT (n=1,037) or EBRT+HDR, n=438) at William Beaumont Hospital. For IGRT, the CTV included the prostate and proximal seminal vesicles only. Median dose (minimum to cl-PTV) delivered via 3D conformal RT or intensity-modulated RT was 75.6 Gy (range: 73.8-79.2 Gy). For EBRT+HDR, the whole pelvis was treated to 46 Gy + 2 HDR implants with a median of 10.5 Gy (8.75-11.5 Gy) per implant. 208 patients from each group were matched based on criteria of pretreatment PSA ± 4 ng/mL, same Gleason score, T stage ± 2 sublevels, and use of neoadjuvant androgen deprivation therapy (ADT). Results: Mean follow-up was 5.1 years for IGRT vs 7.0 years for EBRT+HDR. Mean pretreatment PSA was 9 for both groups. Mean Gleason was 7 for both groups. EBRT+HDR patients were younger (67 vs 71 years, p<0.01) with a higher percentage of positive biopsy cores (51% vs 39%, p<0.01). Intermediate risk patients comprised 78% and 76% for IGRT and EBRT+HDR, respectively (p=0.56). 42% in each treatment group received neoadjuvant or concurrent ADT. 5-year biochemical control (BC) based on the Phoenix definition was 91% for IGRT vs 87% for EBRT+HDR (p=0.60). For intermediate-risk, 5-year BC was 94% vs 87% (p=0.71) and was 86% vs 86% (p=0.83) for high-risk patients. No significant differences were noted between the 2 groups for local recurrence, distant metastasis, clinical failure, overall survival, and cause-specific survival. Conclusions: In this matched-pair analysis of 416 patients, treatment of intermediate and high-risk prostate cancer with either offline adaptive IGRT or EBRT+HDR yielded excellent clinical outcomes without significant differences. The omission of pelvic radiotherapy in the IGRT patients did not appear to be associated with poorer clinical outcomes with modern high-dose RT. No significant financial relationships to disclose.

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Rahman, Rifaquat, Lorenzo Trippa, Geoffrey Fell, Eudocia Lee, Isabel Arrillaga-Romany, Mehdi Touat, Christine McCluskey, et al. "CTNI-11. CC-115 IN NEWLY DIAGNOSED MGMT UNMETHYLATED GLIOBLASTOMA IN THE INDIVIDUALIZED SCREENING TRIAL OF INNOVATIVE GLIOBLASTOMA THERAPY (INSIGHT): A PHASE II RANDOMIZED BAYESIAN ADAPTIVE PLATFORM TRIAL." Neuro-Oncology 22, Supplement_2 (November 2020): ii43—ii44. http://dx.doi.org/10.1093/neuonc/noaa215.178.

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Abstract BACKGROUND CC-115 is an oral, CNS-penetrant, selective inhibitor of mammalian target of rapamycin kinase (mTOR) and deoxyribonucleic acid-dependent protein kinase (DNA-PK). Both targets are important in glioblastoma; PI3K/Akt/mTOR signaling is hyperactive in most glioblastomas, and DNA-PK is integral to repair of radiotherapy-mediated DNA damage. To investigate CC-115 in newly diagnosed glioblastoma and explore potential genomic biomarker associations, CC-115 was evaluated in the Individualized Screening Trial of Innovative Glioblastoma Therapy (INSIGhT) trial, an adaptive platform trial designed to efficiently test experimental agents. METHODS Adults with newly diagnosed MGMT-unmethylated glioblastoma, with genomic data available, are eligible for this ongoing trial. Patients are adaptively randomized to one of several experimental arms or the control arm: standard radiotherapy with concurrent and adjuvant temozolomide. The primary endpoint is overall survival (OS). Patients randomized to CC-115 (10mg po BID) received it concurrently with radiotherapy and as adjuvant monotherapy. As the first in-human use of CC-115 with radiation, a safety lead-in 3 + 3 design was used. RESULTS Twelve patients were randomized to CC-115; seven patients had possible treatment-related CTCAE grade > 3 toxicity, including four pre-specified dose-limiting toxicities: liver function abnormality (n=1), hyperlipidemia (n=1), lipase elevation (n=1) and cerebral edema (n=1). There was no significant difference in progression-free survival (PFS, median 4.2 months [CC-115] vs. 5.2 months, p=0.9) or OS (median 10.1 months [CC-115] vs. 14.5 months, p=0.9) compared to the 50 patients randomized to the control arm. Based on early PFS results, randomization probability to CC-115 decreased from 25% to < 10% at time of the trial arm closure. CONCLUSION Concurrent and adjuvant CC-115 was associated with toxicity and failed to improve PFS or OS. The INSIGhT trial design allowed for more efficient testing of CC-115, decreasing patients and resources allocated to a therapy that was discontinued due to concerns about toxicity and unfavorable risk-to-benefit ratio.

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Journal articles on the topic 'Adaptive radiotherapy (ART)'

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