Hearing Loss and Volumetric Growth Rate in Observed Vestibular Schwannoma Patients

Objective: Hearing loss is the most common presenting symptom for patients with vestibular schwannomas, yet the relationship between hearing loss and tumor growth remains unclear. This study aimed to clarify how hearing is affected in untreated VS based on volumetric growth rates determined from high-resolution imaging.

Methods: A total of 128 treatment-naive patients diagnosed with unilateral VS between 2012 and 2018 with serial audiometric assessment and MRIs were reviewed. Tumor growth rates were determined from initial and final tumor volumes, with an average follow-up time of 27.4 months (range: 0.7–122.2 months). Hearing changes were based on pure tone averages, word recognition scores, and AAO-HNS hearing class. Primary outcomes were the loss of Class A hearing and loss of serviceable hearing, estimated using the Kaplan–Meier method and with associations estimated from Cox proportional hazards models.

Results: Increasing volumetric tumor growth rate was associated with elevated risk of loss of Class A hearing (HR: 1.2 for increase of 100% per year; p = 0.031) and serviceable hearing (HR: 1.2; p = 0.011) in multivariable model with initial tumor size, which was also associated with increased risk of losing class A (HR: 1.5 for 1-cm³ increase; p = 0.047) and serviceable hearing (HR: 1.3; p = 0.016). Faster growing tumors were the primary driver of the relationship between growth rate and hearing loss, with tumors growing faster than 80% per year associated with a significantly elevated risk of losing Class A (HR: 3.1; p = 0.006) and serviceable hearing (HR: 2.3; p = 0.044). Patients with tumors growing faster than 80% per year had median times to loss of class A hearing of 26.7 months and loss of serviceable hearing of 42.9 months, compared with patients with tumors growing slower than 80% per year with median times to loss of class A hearing of 72.4 months and loss of serviceable hearing of 85.5 months (p = 0.01 and p = 0.03, respectively).

Conclusion: This study found significance associations with tumor growth rates and initial tumor size with loss of class A and serviceable hearing. These findings underscores that tumor growth rate may be an important tumor characteristic contributing to hearing loss.

Publication History

Article published online:
12 February 2021