P11.62.A GENDER-RELATED DIFFERENCES IN PATIENTS CHARACTERISTICS, AND TREATMENT OUTCOME IN A COMPARATIVE STUDY OF MICROSURGERY AND RADIOSURGERY OF VESTIBULAR SCHWANNOMA

Abstract

Abstract BACKGROUND Gender-related differences in patients with sporadic, unilateral vestibular schwannoma (VS) are poorly investigated so far. In studies focusing on natural history, tumor growth was described to be indifferent in either sex. However, it remains unclear whether patient’s sex affects the treatment response to stereotactic radiosurgery (SRS) or microsurgical resection (SURGERY). This study elucidates sex-related differences in VS care. MATERIAL AND METHODS This is a retrospective multi-center cohort study. Data was retrospectively collected from two large centers involved in the treatment of vestibular schwannomas for patients between 2005 und 2011 to enable long-term follow-up (FU). Tumor size was classified by Koos Classification. Previously treated VS and patients with Neurofibromatosis were excluded. Clinical state was reported by House and Brackmann (H&B) and Gardner-Robertson (G&R) scale (with H&B<3 and G&R 1-2 considered as good outcome), and Recurrence-free-survival (RFS) was assessed radiographically by contrast-enhanced MR imaging. Data on VS-associated symptoms like trigeminal affection, tinnitus, and vertigo/imbalance were also collected. RESULTS The study population included N=901 patients, who were treated in both centers. N=502 (56%) VS patients were female and N=399 (44%) were male. At time of treatment, women (56 years SD±13.50) were significantly older in age then men (53 years SD±13.80) (p=0.001). Tumor size, cystic morphology, intracanalicular extension, provided care (SRS, SURGERY), treatment related complications, and extent of surgical resection were insignificant in both gender-groups. The incidence of relevant preoperative vertigo was higher in women (67%) then in men (55%) (p=0.002). Pre- and postoperative facial function, hearing loss, and trigeminal symptoms were similar in both groups. Overall incidence of recurrence was insignificant (p=0.106). However, the in subgroups, tumor control with SRS was significantly worse in women compared to men (p=0.035). CONCLUSION Provided Care, functional outcome and peri-interventional morbidity were the same in either sex. Relevant vertigo was significantly more often present in women. The incidence of recurrence is higher in women with VS, when treated with SRS compared to men, although tumor characteristics were similar. Additional research is needed to elucidate gender-related difference in tumor biology affecting the response to VS treatment.