Natural History of Vestibular Schwannomas in Patients Aged 70 and Older

Introduction: Vestibular schwannomas (VS) are benign tumors often managed with observation in small- to medium-sized cases, particularly in older adults. Although the natural history of VS is well-documented, data on patients aged 70 and older remains limited. This study aims to better characterize the natural history of VS in this population.

Methods: A single-institution retrospective chart review was performed on patients who were diagnosed or observing a VS after the age of 70 since 2010. Information was collected on demographics, imaging and surveillance, tumor growth, and treatment. Growth was defined as >=2mm change in the maximum linear tumor length at subsequent imaging.

Results: A total of 166 patients over 70 years of age met inclusion criteria, with 34.7% (n=57) eventually pursuing treatment at an average age of 74.9 years (range 61.2 - 89.9) and 107 patients continuing observation. The average follow-up for all patients was 4.3 (SD 3.2) years, with an average follow-up of 4.6 (SD 2.64 years) for those patients who did not pursue treatment. Overall, 29.3% of patients demonstrated tumor growth, with 24.2% of patients reaching a linear tumor size of 2 cm and a growth rate of 0.77 cm/year. Patients pursuing treatment were significantly more likely to demonstrate growth as compared to those who continued observation (68.9% vs 19.4%, p< 0.001), as well as reaching a maximum tumor length of 2cm (60.4% vs 5.6%, p< 0.001).
When exploring the tumor and growth characteristics between different age cohorts, the risk of growth was significantly higher below 70 (20% vs 8.6%, p=0.02), but did not change after 70 (70-74, 75-79, 80+, p=0.2). Among observation patients aged over 80, 1.4% had a tumor size of 2cm or more compared to 3.9% under 80 (p=0.2).

Conclusions: Patients aged 70 and older with VS managed through observation exhibited a low incidence of tumor growth. These results suggest that potentially lengthening imaging intervals in an older population could be a safe and effective strategy for optimizing surveillance in this population.