Risk factors for treatment-related sensorineural hearing loss and hearing aid use in medulloblastoma patients: an observational cohort study.

Abstract

This study aimed to analyze treatment-related risk factors for sensorineural hearing loss (SNHL) and an indication for hearing aids (IHA) in medulloblastoma patients after craniospinal radiotherapy (CSRT) and platin-based chemotherapy (PCth). Atotal of 58patients (116 ears) with medulloblastoma and clinically non-relevant pre-treatment hearing thresholds were included. Cranial radiotherapy and PCth were applied sequentially according to the HIT 2000 study protocol or post-study recommendations, the NOA-07 protocol, or the PNET (primitive neuroectodermal tumor) 5MB therapy protocol. Audiological outcomes up to amaximum post-therapeutic follow-up of 4years were assessed. The incidence, post-treatment progression, and time-to-onset of SNHL, defined as Muenster classification grade ≥MS2b, were evaluated. Risk factors for IHA were analyzed separately. While 39patients received conventionally fractionated RT (CFRT; group1), 19patients received hyperfractionated RT (HFRT; group2). Over amedian follow-up of 40months, 69.2% of ears in group1 experienced SNHL ≥MS2b compared to 89.5% in group2 (p = 0.017). In multivariable Cox regressions analysis, younger age and increased mean cochlear radiation dose calculated as the equivalent dose in 2‑Gy fractions (EQD2) were associated with time-to-onset of SNHL ≥MS2b (p = 0.019 and p = 0.023, respectively) and IHA (p < 0.001 and p = 0.016, respectively). Tomotherapy and supine positioning were associated with alower risk for IHA in univariable modelling only (p = 0.048 and p = 0.027, respectively). Young age and cochlear EQD2 Dmean ≥40 Gy are significant risk factors for the incidence, degree, and time-to-event of SNHL as well as for IHA in medulloblastoma patients.