Tratamiento no quirúrgico del schwannoma vestibular / Non surgical treatment of vestibular schwannoma

Introducción y objetivos: Valorar los resultados de control local y complicaciones en el tratamiento del schwannoma vestibular tratado con radiaciones. Métodos: Estudio retrospectivo de 194 pacientes diagnosticados de schwannoma vestibular, tratados de manera consecutiva bien con observación o bien con radiaciones (bien radiocirugía o radioterapia esterotáctica fraccionada) de 1997 a 2012. Analizamos el control local de los tumores, así como de las complicaciones secundarias al tratamiento con radiocirugía. Resultados: El 68% (132 tumores) son inferiores a 2 cm es decir grado I-II de la clasificación de Koos, 22 pacientes (13%) con tumores grandes grado IV, el resto (40 pacientes) son grado III. Los tumores relacionados con la neurofibromatosis (NF2) representan el 3,6% (6 tumores en 4 pacientes). El control tumoral para los pacientes tratados con radiaciones es del 97% a 5 años, con un seguimiento mediano de 80,4 meses. Para los tumores grandes el control local es del 91% a 5 años. La supervivencia libre de complicaciones crónicas es del 89% a 5 años. De los 50 tumores a los que se realizó seguimiento, 28 (58%) continúan en seguimiento al no haberse objetivado crecimiento alguno. Conclusiones: La radiación y el seguimiento con RM, dentro de un enfoque multidisciplinar, es una alternativa a la cirugía en el tratamiento del schwannoma vestibular, con un bajo nivel de complicaciones (AU)

Introduction and objectives: To evaluate the results of local control and complications in the treatment of vestibular schwannoma treated with radiation. Methods: A retrospective study of 194 patients diagnosed with vestibular schwannoma, treated consecutively with radiation (either stereotactic radiosurgery or fractionated radiotherapy) from 1997 to 2012. We analyze the local control of tumors, as well as secondary complications to treatment with radiation. Results: A total of 132 (68%) tumors 68% are grade I-II tumors of the Koos classification, 40 (19%) are grade III, and 22 (13%) are grade IV. The tumors associated with neurofibromatosis (NF2), are 3.6% (6 tumors in 4 patients). The tumor control for the overall serie is 97% at 5 years, with a median follow-up of 80.4 months. For large tumors the local control is 91% at 5 years. Free survival of chronic complications is 89% at 5 years. Aditionally, 50 tumors were subjected to regular follow-up with MRI without treatment, and 28 (58%) did not experienced tumor growth. Conclusions: Radiation and follow up with MRI, are an alternative to surgery in the treatment of vestibular schwannoma, with a low level of complications inside of multidisciplinary approach (AU)

Support vector machine classification of brain metastasis and radiation necrosis based on texture analysis in MRI.

PURPOSE: To develop a classification model using texture features and support vector machine in contrast-enhanced T1-weighted images to differentiate between brain metastasis and radiation necrosis. METHODS: Texture features were extracted from 115 lesions: 32 of them previously diagnosed as radiation necrosis, 23 as radiation-treated metastasis and 60 untreated metastases; including a total of 179 features derived from six texture analysis methods. A feature selection technique based on support vector machine was used to obtain a subset of features that provide optimal performance. RESULTS: The highest classification accuracy evaluated over test sets was achieved with a subset of ten features when the untreated metastases were not considered; and with a subset of seven features when the classifier was trained with untreated metastases and tested on treated ones. Receiver operating characteristic curves provided area-under-the-curve (mean ± standard deviation) of 0.94 ± 0.07 in the first case, and 0.93 ± 0.02 in the second. CONCLUSION: High classification accuracy (AUC > 0.9) was obtained using texture features and a support vector machine classifier in an approach based on conventional MRI to differentiate between brain metastasis and radiation necrosis.

Non surgical treatment of vestibular schwannoma.

INTRODUCTION AND OBJECTIVES: To evaluate the results of local control and complications in the treatment of vestibular schwannoma treated with radiation. METHODS: A retrospective study of 194 patients diagnosed with vestibular schwannoma, treated consecutively with radiation (either stereotactic radiosurgery or fractionated radiotherapy) from 1997 to 2012. We analyze the local control of tumors, as well as secondary complications to treatment with radiation. RESULTS: A total of 132 (68%) tumors 68% are grade I-II tumors of the Koos classification, 40 (19%) are grade III, and 22 (13%) are grade IV. The tumors associated with neurofibromatosis (NF2), are 3.6% (6 tumors in 4 patients). The tumor control for the overall serie is 97% at 5 years, with a median follow-up of 80.4 months. For large tumors the local control is 91% at 5 years. Free survival of chronic complications is 89% at 5 years. Additionally, 50 tumors were subjected to regular follow-up with MRI without treatment, and 28 (58%) did not experienced tumor growth. CONCLUSIONS: Radiation and follow up with MRI, are an alternative to surgery in the treatment of vestibular schwannoma, with a low level of complications inside of multidisciplinary approach.

Prognostic factors in squamous cell lip carcinoma treated with high-dose-rate brachytherapy.

BACKGROUND: The purpose of this study was for us to present our analysis of the results and prognostic factors in squamous lip carcinoma treated with high-dose-rate (HDR) brachytherapy. METHODS: From 1999 to 2010, 102 patients were treated with HDR-brachytherapy, 54 with T1, 33 with T2, and 15 with T4. Eight cases were N+. Twenty-one patients were treated with surgery plus brachytherapy because of close/positive margins. Nine fractions of 5 Gy were given over 5 days in 67% of the patients. Elective neck treatment was performed in 23 cases. RESULTS: The 10-year actuarial local control was 94.6%, nodal regional control was 88.6%, disease-free survival was 84.6%, and cause-specific survival was 93.2%. In the univariate analysis, T4 tumors had higher risk of local failure and T2 of regional relapse. In the multivariate analysis, skin involvement was the only significant factor for tumor progression. CONCLUSION: HDR-brachytherapy yields excellent local control rates. Skin involvement increases the risk of local and cervical recurrence. Elective neck treatment should be done in T2 to T4 tumors or with skin or commissure involvement.