Prevalence of Sporadic Vestibular Schwannoma: Reconciling Temporal Bone, Radiologic, and Population-based Studies.

Objective: Reported epidemiologic data surrounding vestibular schwannoma (VS) are controversial. Temporal bone prevalence studies have suggested that VS affects up to 2.4% of the population, whereas magnetic resonance imaging (MRI) studies have reported VS to affect 0.017%. Moreover, existing population-based data seem to underestimate the commonness of VS. In an attempt to reconcile temporal bone, radiologic, and population-based reports regarding VS, the current study was conceived to determine the modern prevalence of VS using a unique epidemiological database.
Patients: All persons living in Olmsted County, Minnesota on January 1, 2017 with a confirmed diagnosis of sporadic VS identified using the Rochester Epidemiology Project (REP) medical records-linkage system.
Main Outcome Measures: Prevalence of all VS and asymptomatic, incidentally diagnosed VS.
Results: Sixty-seven persons from a population of nearly 160,000 were living with VS on January 1, 2017, resulting in a point prevalence of 42.0 per 100,000 persons. The prevalence increased with older age, reaching 212.4 per 100,000 in those ≥ 70 years. Including only persons who have undergone head MRI, the prevalence of asymptomatic, incidentally diagnosed VS was 69.9 per 100,000 among adults age 20 years and older.
Conclusions: Using the unique infrastructure of the REP, the current study suggests that the clinical prevalence of sporadic VS approximates 1 in 2,000 adults and 1 in every 500 persons aged 70 years and older, with the prevalence of incidentally diagnosed tumors closely paralleling past MRI studies. These data characterize a shift in the modern patient demographic of sporadic VS, as now many people bearing a diagnosis of VS would have previously died without knowledge of their disease. Moreover, they typify an unfolding transition from an era of microsurgery and radiosurgery to the beginnings of an era that will be largely comprised of "chronic disease management."