Auswahl der wissenschaftlichen Literatur zum Thema „Schwannove bunky“

Schwannoma is a neurogenic benign tumour arising from the proliferation of Schwann cells present in the peripheral nerve sheath of myelinated nerves. This proliferation can hypothetically appear in every anatomic region of the human body, but the nerve sheath tumors rarely occur within the larynx. In this paper the authors discuss the case of a 74-year-old female who presented to Emergency Unit (EU) for an important acute respiratory distress. Airway flexible endoscopy revealed a bulky mass of the aryepiglottic fold measuring 3.5 cm in diameter. The patient underwent tracheotomy and a single-step surgical excision treatment of the mass which was recognized as a schwannoma at pathological examination. Tracheotomy was closed 2 weeks postoperatively. After 18 months of followup, the patient is alive and free of disease and her voice had improved markedly.

Neurilemmomas are benign neoplasms presumedly derived from Schwann cells which rarely originate within the central nervous system. Moreover, their intraventricular location has been seldom noticed with less than 30 cases reported worldwide. Here, we add another case study to the record as well as the fifth one in Latin American population. A 16-year-old boy without significant past clinical data debuted with headache and progressive left eye blindness during six months. Neuroimaging scans showed a bulky, multiloculated, intraventricular tumour emerging from the posterior horn of the left lateral ventricle. Microscopically, the lesion put on view the classical schwannian histology: spindle cells arranged in both compact and loosely textured areas. Verocay bodies were not present but vessel hyalinisation, pericellular reticulin, and senescent atypia were observed. The immunoperoxidase reactions were also consistent with neurilemmal differentiation; however, glial fibrillary acidic protein expression was widespread and unexpectedly seen. Traditionally conceived as “nerve sheath tumours” the dual immunophenotype herein demonstrated points to a different histogenetical pathway other than sheer Schwann cell derivation. As previously advised by some authors, neoplastic transformation from a multipotent stem cell may explain the occasional finding of these tumours in unconventional intracranial compartments.

OBJECTIVEThe CO2 laser has been used on an intermittent basis in the microsurgical resection of brain tumors for decades. These lasers were typically cumbersome to use due to the need for a large, bulky design since infrared light cannot be transmitted via fiber-optic cables. Development of the OmniGuide cable, which is hollow and lined with an omnidirectional dielectric mirror, has facilitated the reintroduction of the CO2 laser in surgical use in a number of fields. This device allows for handheld use of the CO2 laser in a much more ergonomically favorable configuration, holding promise for microneurosurgical applications. This device was introduced into the authors’ practice for use in the microsurgical resection of skull base tumors, including vestibular schwannomas.METHODSThe authors reviewed the initial 41 vestibular schwannomas that were treated using the OmniGuide CO2 laser during an 8-month period from March 2010 to October 2010. The laser was used for all large tumors, and select medium-sized tumors were treated via both the translabyrinthine and retrosigmoid approaches. The estimated time of tumor resection and estimated blood loss were obtained from operating room records. Data regarding complications, facial nerve and hearing outcomes, and further treatment were collected from hospital and clinic records, MRI reports, and direct review of MR images. Time of resection and blood loss were compared to a control group (n = 18) who underwent surgery just prior to use of the laser.RESULTSA total of 41 patients with vestibular schwannomas were surgically treated. The median estimated time of tumor resection was 150 minutes, and the median estimated blood loss was 300 ml. The only operative complication was 1 CSF leak. Thirty-eight patients had normal facial nerve function at late follow-up. The median MRI follow-up was 52 months, and, during that time, only 1 patient required further treatment for regrowth of a residual tumor.CONCLUSIONSThe OmniGuide CO2 laser is a useful adjunct in the resection of large vestibular schwannomas. This device was used primarily as a cutting tool rather than for tumor vaporization, and it was found to be of most use for very large and/or firm tumors. There were no laser-associated complications, and the results compared favorably to earlier reports of vestibular schwannoma resection.

Abstract IntroductionThe survival of children with Hodgkin lymphoma have increased significantly raising the issue of decreasing late effects by using risk adapted treatment. Hodgkin lymphoma has different epidemiologic features in developed and developing countries. In this study the epidemiologic, clinical characteristics and outcome of children with Hodgkin disease treated with a risk adapted treatment over a 25 year period are evaluated. MethodsThis retrospective study evaluates the clinical characteristics and outcome of 122 children treated with the same institutional risk-adapted protocol in the Istanbul University, Oncology Institute between 1991-2016. Clinical staging was done according to Ann-Arbor staging, all patients had biopsy confirmation and the WHO histopathological classification was used. Imaging (ultrasound, CT/MRI and/or PET-CT since 2004) was done in all patients. Bone marrow aspiration and biopsy was done for all with B symptoms or risk group 2 and 3. Risk group 1 (clinical group IA/B and IIA) recieved 2 courses of ABVD (adriamycin 25 mg/m2, bleomycin 10 U/m2, vinblastin 6 mg/m2 and dacarbazine 375 mg/m2 , day 1 and 15) chemotherapy, risk group 2 (stage IIB and IIIA) 4 courses of ABVD, risk group 3 patients (IIIB,IVA/B) 6 courses of COPP/ABV (cyclophosphamide 600 mg/m2, vincristine 1.4 mg/m2 on day 1, procarbazine 100 mg/m2 day1-7, prednisolone 40 mg/m2 day1-14; adriamycine 35 mg/m2, bleomycin 10 U/m2, vinblastine 6 mg/m2 day 8) chemotherapy, each course administered every 28 days. All patients recieved involved field radiotherapy 15-25 Gy adjusted to age (15 Gy for < 5, 20 Gy for 5-10, 25 Gy for >10 years old), + 5 Gy for bulky disease and/or partial response to chemotherapy. Results There were 83 males and 39 females (M/F: 2.1) with a median age of 10 (2-18) years. The most frequent histological subtypes were mixed cellularity (41%) and nodular sclerosing (41%). The most common involved site was the neck (cervical and supraclavicular lymph nodes) (%85). The median follow up period was 6 1/12 years (1-25 years). The 5 year event free survival and survival were 82% and 97% for all patients; they were 86% and 97% for risk 1 (48 patients), 80% and 96% for risk 2 (29 patients), 79% and 97% for risk 3 (45 patients) . B symptoms were present in 46%; %54 were staged as I-II; 46% as stage III-IV. When classified according to two time periods: before and after 2000, the median age increased [9 (2-17) vs 11 (3-18) years], M/F ratio decreased [2.7 (36/13) vs 1.8 (47/26)] and the most common histological subtype were mixed cellularity (51%) vs nodular sclerosing (49%) respectively. The 5 year event free survival and survival were 79% and 95% before 2000 and 83,5% and 98% after 2000 respectively. Ebstein Barr Virus-Latent membrane Protein (EBV-LMP1) was found to be positive by immunohistochemistry in all tumor samples of 21 patients analyzed, all were treated before 2000. During follow-up no clinically evident cardiotoxicity or pulmonary toxicity has been observed. Three patients developed secondary tumors (Langerhans cell histiocytosis, schwannoma, non-Hodgkin's lymphoma). ConclusionThe epidemiologic features of HL is related to socioeconomic status. In our cohort, the oberved change in epidemiologic features within 25 years, such as the increase in median age, decrease in the M/F ratio and increase in nodular sclerosing subtype, is thought to be related to the socioeconomic development. A high survival rate has been achieved with the institutional risk-adapted protocol for all risk groups. The use of risk adapted protocols providing efficient and least toxic treatment is very important in pediatric Hodgkin lymphoma. Disclosures No relevant conflicts of interest to declare.

Abstract Background Neurogenic tumors of the larynx are rare, with few cases having been reported in the literature. Schwannomas are responsible for 0.1% of all benign tumors of the larynx. They arise in the sheaths of the peripheral, autonomic, and cranial nerves. The objective of this report is to describe a case of a bulky laryngeal schwannoma, the surgical procedure for its removal, and the long-term patient follow-up. Case presentation A 19-year-old Brazilian woman presented to our institution with a complaint of progressive dyspnea over the preceding year, as well as dysphonia, dysphagia for solids, and globus pharyngeus. Direct rigid laryngoscopy showed a supraglottic tumor obstructing approximately 90% of the larynx. With the symptoms progressing to severe dyspnea, an emergency tracheostomy was performed. After infusion of intravenous contrast, magnetic resonance imaging revealed a mass lesion with intense, heterogeneous contrast enhancement along the posterior wall of the hypopharynx, blocking all of the lumen and measuring 2.8 cm and 2.2 cm at its largest diameters. The image suggested a neoplastic lesion. The patient underwent open surgery for tumor resection. Her postsurgical recovery was uncomplicated. Histopathology and immunohistochemistry revealed the tumor to be a laryngeal schwannoma. Conclusion The definitive diagnosis of laryngeal lesions can be difficult, and histopathology plays a pivotal role. Laryngeal schwannomas are rare; however, tumors can become large and may ultimately lead to airway obstruction.

Pre regeneráciu a rast poranených nervových vlákien bolo preskúmaných mnoho postupov, no výsledný rast axónov je často náhodný až dezorganizovaný a odráža sa na zložitejšom zotavovaní pacienta. V tejto práci boli vyrobené nové skafoldy s mikroštruktúrnymi a mechanickými vlastnosťami nervového skafoldu pomocou metódy freeze-casting. Konkrétne boli vyrobené biokeramické skafoldy na báze fosforečnanov vápenatých, oxidu titaničitého alebo oxidu zirkoničitého. Pomocou kontrolovaného rastu ľadu v jednom smere bola pripravená orientovaná mikroštruktúra. Pozorovanie pomocou skenovacej elektrónovej mikroskopie potvrdilo lineárne orientované póry (lamelárny systém), v ktorých priemerná veľkosť pórov klesala so zvyšujúcou sa rýchlosťou mrazenia. Skafoldy pripravené pomocou mrazenia v tekutom dusíku vykazovali vynikajúce mechanické vlastnosti, kde pevnosť v ohybe bola získaná v rozmedzí 10–17 MPa. Tie isté skafoldy mali vzdialenosť medzilamelamelárnych priestorov 10–30 µm, ktorých parametre sú vhodné pre nervové skafoldy. Biokompatibilita bola vyhodnotená pomocou Schwannových buniek in vitro, kde bola pozorovaná adhézia a rast v lamelárnom smere. Cytotoxické testy odhalili negatívny vplyv vyššej koncentrácie vápnika na prežitie Schwannových buniek. Pripravené skafoldy mali schopnosť tvorby apatitu na povrchu v podobe embryonálnych a nukleačných centier a apatitu samotného. Skafoldy na báze fosforečnanov vápenatých a oxidu titaničitého vykazovali sľubné regeneračné vlastnosti, konkrétne adhéziu a rast prostredníctvom pórovitej štruktúry a taktiež vynikajúce mechanické vlastnosti.