Severe Hearing Loss in Children With Central Nervous System Tumors: A Population‐Based Cancer in Young People in Canada (CYP‐C) Report

Purpose Children with central nervous system (CNS) tumors are prone to treatment‐related hearing loss (HL) and subsequent functional impairment. This study reports a dedicated population‐based analysis of CNS tumor‐specific rates and predictors of early severe HL. Methods A cohort study of children ≤15 years diagnosed with CNS tumors between 2001 and 2019 through the Cancer in Young People in Canada (CYP‐C) program. The primary outcome was Grade 3 and 4 severe HL within 5 years following diagnosis. Results Among 3201 children with CNS tumors, 5.1% experienced early severe HL. Children with medulloblastoma ( N = 570) and ATRT/other embryonal tumors ( N = 269) had higher rates of early HL (16.1%, 15.2%, respectively). Cisplatin was administered to 80.1% of children with embryonal tumors, and 67.3% received radiotherapy. In children with medulloblastoma, age less than 6 years at diagnosis (OR 2.4, 1.5–3.8; vs. ≥6 years), radiation (OR 3.5, 1.6–7.6), and cisplatin (OR 20.4, 1.3–329.7) predicted early severe HL. Younger age at diagnosis doubled the probability of early severe HL (10.6% in <6 years vs. 4.8% in ≥6 years), while radiation exposure tripled the probability across age groups (29.8% and 10.6% if <6 years; 15.3% and 4.8% in ≥6 years). In children with ATRT/other embryonal tumors, cisplatin (OR 31.6, 1.9–521.9) was the sole predictor of early severe HL. Conclusions High rates of early HL were observed in children with embryonal tumors. Younger children who received radiotherapy had higher probabilities of early HL, suggesting an additive interaction between age and radiation. Standardized otoprotection and research on cisplatin avoidance and therapy de‐escalation in young children with embryonal tumors are urgently needed.