The management of small- to medium-sized vestibular schwannoma (VS) remains controversial. Despite a lack of compelling evidence supporting one treatment modality over others, many providers and institutions remain highly biased toward one particular therapy-microsurgery, radiation, or primary observation. The objective of the current study was to estimate the impact of geography on disease presentation and initial treatment of VS in the United States. An analysis of the Surveillance, Epidemiology, and End Results (SEER) database identified 9761 patients with VS that were managed across the 16 SEER geographic registry areas. Univariate analyses demonstrated strong associations between geographic location and tumor size at diagnosis (P < 0.0001). When analyzing the 6115 subjects with tumors between 0 and 3 cm in size, multivariable models identified strong associations between place of residence and treatment modality (P < 0.0001). These multivariable models demonstrated that in many cases the impact of place of residence on treatment selection was greater than other established variables such as tumor size and age. To our knowledge, this is the first study to evaluate geographic trends in VS patient demographics, tumor size and management in the United States. These data suggest that disease presentation and treatment modality are significantly influenced by regional referral patterns, provider or institutional treatment preferences, and regional availability of subspecialty expertise. Understanding geographic bias is important for patients, referring physicians, and treatment providers alike. Until there is clear evidence supporting one therapy over others, multidisciplinary consultation with a minimum of a neurotologist, neurosurgeon, and radiation oncologist or radiosurgeon should be offered in order to provide balanced counseling and accurate informed consent.
Keywords: Acoustic neuroma; Microsurgery; Radiosurgery; Skull base; Vestibular schwannoma.