DEATH FROM A MALIGNANT CEREBELLOPONTINE ANGLE TRITON TUMOR DESPITE STEREOTACTIC RADIOSURGERY - CASE-REPORT

Malignant vestibular nerve tumors are rare: to date, only three cases have been reported in the literature. The authors report a case of an eighth cranial nerve tumor that progressed 5 years after stereotactic radiosurgery. The patient was a 44-year-old man who underwent stereota ctic radiosurgery for a 27-mm cerebellopontine angle tumor that was di scovered on investigation of tinnitus and hearing loss. He developed f acial weakness after 5 years, and repeated imaging revealed tumor enla rgement. Despite complete microsurgical excision, the tumor rapidly re curred locally and subsequently disseminated within the neuraxis. The patient died 1 year after tumor progression was detected. Histopatholo gical analysis revealed a malignant spindle cell neoplasm with frequen t mitotic figures. The presence of positive rhabdoid elements on immun ohistochemical studies confirmed that it was a triton tumor. The autho rs review the relevant literature concerning the classification and ma nagement of malignant vestibular nerve tumors and discuss the implicat ions of tumor progression after stereotactic radiosurgery.