Conservative management of vestibular schwannomas: an effective strategy

Stimulated by the availability of a larger sample of patients and a longer follow-up period, we update our experience with conservative management of vestibular schwannomas.

Patients with intracanalicular and small/medium-sized tumors have been followed prospectively at a tertiary referral center.

One hundred twenty-three patients affected by sporadic vestibular schwannoma were primarily observed by means of magnetic resonance imaging scans. In case of significant tumor growth (> or =2 mm), patients were either surgically treated or submitted to radiotherapy, but, not rarely, they continued to follow the "wait-and-scan" policy. Tumor-size changes over time were also evaluated with hearing function. Statistical analysis with predictive growth factors was performed.

Almost two thirds (64.5%) of the cases did not show tumor growth during the entire period of observation (mean follow-up period, 4.8 yrs). Among growing tumors, 16 patients were surgically treated with no complications or facial nerve palsy. Less than half (45.5%) of the patients presented useful hearing (classes A and B of the American Academy of Otolaryngology-Head and Neck Surgery classification) at diagnosis, and 41 (73.2%) patients had preserved hearing during follow-up independently from the tumor growth rate.

Conservative management of vestibular schwannoma appears to be a safe procedure because most tumors do not grow and surgical outcomes are not affected by possible delays. In the great majority of cases, useful hearing is maintained over time. Because of the irregular behavior of the tumor, periodic neuroradiologic scans are mandatory to limit late surgical risks.