ABSTRACT
BACKGROUND: Ototoxicity is a known side effect of combined radiation therapy and cisplatin chemotherapy for the treatment of medulloblastoma. The delivery of an involved field boost by intensity modulated radiation therapy (IMRT) may reduce the dose to the inner ear when compared with conventional radiotherapy. The dose of cisplatin may also affect the risk of ototoxicity. A retrospective study was performed to evaluate the impact of involved field boost using IMRT and cisplatin dose on the rate of ototoxicity. METHODS: Data from 41 medulloblastoma patients treated with IMRT were collected. Overall and disease-free survival rates were calculated by Kaplan-Meier method Hearing function was graded according to toxicity criteria of Pediatric Oncology Group (POG). Doses to inner ear and total cisplatin dose were correlated with hearing function by univariate and multivariate data analysis. RESULTS: After a mean follow-up of 44 months (range: 14 to 72 months), 37 patients remained alive, with two recurrences, both in spine with CSF involvement, resulting in a disease free-survival and overall survival of 85.2% and 90.2%, respectively.Seven patients (17%) experienced POG Grade 3 or 4 toxicity. Cisplatin dose was a significant factor for hearing loss in univariate analysis (p < 0.03). In multivariate analysis, median dose to inner ear was significantly associated with hearing loss (p < 0.01). POG grade 3 and 4 toxicity were uncommon with median doses to the inner ear bellow 42 Gy (p < 0.05) and total cisplatin dose of less than 375 mg/m2 (p < 0.01). CONCLUSIONS: IMRT leads to a low rate of severe ototoxicity. Median radiation dose to auditory apparatus should be kept below 42 Gy. Cisplatin doses should not exceed 375 mg/m2.
Subject(s)
Cerebellar Neoplasms/radiotherapy , Hearing Loss/diagnosis , Hearing/radiation effects , Medulloblastoma/radiotherapy , Radiation Tolerance , Radiotherapy, Intensity-Modulated/adverse effects , Adolescent , Adult , Child , Child, Preschool , Female , Follow-Up Studies , Hearing Loss/etiology , Humans , Infant , Infant, Newborn , Male , Prognosis , Radiotherapy Dosage , Radiotherapy Planning, Computer-Assisted , Retrospective Studies , Young AdultABSTRACT
A via biliar é uma sede frequente de variaçöes anatômicas. Seu conhecimento é importante principalmente sob o ponto de vista cirúrgico. Com o objetivo de estudar as principais alteraçöes anatômicas da via biliar principal "in vivo", investigaram-se retrospectivamente 86 colangiografias peroperatórias de colescistectomias por litíase biliar. Os resultados mostraram variaçöes da drenagem da via biliar direita em 13,1 por cento dos casos . A confluência dos ductos principais apresentou variaçöes em 14,5 por cento dos casos. O ducto cístico apresentou trajeto retilíneo em 87,5 por cento, dos casos, sendo espiralado em 2,5 por cento e inserido próximo ao duodeno em 10 por cento. Concluindo, o exame colangiográfico peroperatório evidenciou algumas variaçöes morfológicas. Julgamos prudente a realizaçäo desse exame näo só para caracterizar doenças das vias biliares, mas também para orientar o cirurgiäo, com vista a possíveis alteraçöes anatômicas que podem ser causa de incidentes cirúrgicos