Audiometric Monitoring and Its Determinants in Patients Undergoing Chemoradiotherapy for Head and Neck Cancer

Audiometric monitoring is recommended for patients receiving ototoxic (chemo)radiotherapy for head and neck cancer (HNC), yet real-world uptake is poorly characterized and potentially inequitable. We quantified the uptake and timing of audiometric testing and examined rural-urban residence and age as candidate determinants.

We conducted a single-center retrospective cohort study of 70 consecutive patients with HNC treated with radiotherapy between November 2024 and September 2025, comparing rural (n = 32) and urban (n = 38) residents. Outcomes were audiometric testing at treatment initiation, repeat audiometry during follow-up, and post-treatment hearing change. Analyses included Fisher's exact and Mann-Whitney U tests, Spearman correlations, Firth-penalized logistic regression, inverse probability of treatment weighting (IPTW), restricted cubic splines, and sensitivity analyses.

Audiometry at treatment initiation was performed in 31/70 patients (44.3%) and repeat audiometry in only 10/70 (14.3%); among tested patients with documented dates, just 19.4% underwent audiometry before the first radiotherapy fraction, so that a true pre-exposure baseline existed for only 6/70 patients (8.6%). Uptake at initiation was 53.7% with concurrent cisplatin, 14.3% with carboplatin, and 36.4% with radiotherapy alone (p = 0.114). Uptake did not differ by residence (rural 40.6% vs. urban 47.4%; odds ratio (OR) 0.76, 95% confidence interval (CI) 0.30-1.96, p = 0.634), with an IPTW-weighted risk difference of -9.9% (95% CI -30.9 to +11.8). Age was the dominant determinant: uptake fell from 90.5% below 65 years to 24.5% at ≥65 years (adjusted OR per decade 0.32, 95% CI 0.15-0.71, p = 0.005), with significant non-linearity (p = 0.015). Pre-existing hearing loss was associated with lower testing (OR 0.29, 95% CI 0.10-0.91, p = 0.032). Post-treatment hearing change occurred in 54.3% overall (rural 46.9% vs. urban 60.5%, p = 0.336), comprising a subjective hearing complaint in 51.4% and audiometric deterioration in six of the nine patients with paired audiograms.

Audiometric monitoring was incomplete, rarely obtained before irradiation, and steeply age-patterned, whereas rural residence was not associated with lower uptake; structured, exposure-based referral pathways, triggered by planned cisplatin and clinically relevant cochlear dose and applied irrespective of age, are warranted.