Clinical Predictors Leading to Change of Initial Conservative Treatment of 836 Vestibular Schwannomas.

Objective  This study was aimed to determine the role of clinical presentation and tumor characteristics in vestibular schwannoma (VS) at diagnosis, initially treated with conservative management. Design  The study was designed as a retrospective chart review. Setting  The study was prepared at national tertiary referral center for VS patients. Participants  A total of 836 VS patients, initially treated conservatively, were included. Main Outcome Measures  Patient characteristics: age at diagnosis, gender, frequency, and duration of, hearing loss, tinnitus, balance disorder (unsteadiness, dizziness, and vertigo), respectively; and tumor characteristics: laterality, growth, cystic component, and location were analyzed in relation to tumor size at diagnosis and change in treatment strategy. Results  In total, 169 (20%) patients had a change in treatment strategy. Factors at diagnosis that had a high influence on intervention were a short duration of hearing loss (hazard ratio [HR]: 4.8, p  < 0.001) and cystic tumors (HR = 2.6, p  < 0.001). Balance disorders and extracanalicular (EC) tumor location have a medium influence on intervention (HR = 1.6, p  < 0.01). Tumour growth was seen in 55% of the intervention group; we found a significant correlation with a short duration of hearing loss. Cystic VS was significantly higher between the medium and large tumors, 24.3% and 38.1%. ( p  = 0.001), respectively. Conclusions  Patients with a short duration of hearing loss, balance disorders, EC located tumors, and cystic tumors have a significantly higher chance of a change in treatment strategy. Large tumor size at diagnosis and a cystic component were related to age > 65 years at diagnosis.