Comparative Analysis of Hearing Loss Induced by Cisplatin Versus Carboplatin in Locally Advanced Nasopharyngeal Carcinoma: Early to Mid-Term Findings.

Introduction: To investigate the clinical course of ototoxicity induced by induction chemotherapy followed by concurrent chemoradiotherapy (iCRT), and to determine whether replacing cisplatin with carboplatin in iCRT can reduce hearing damage in patients with nasopharyngeal carcinoma (NPC).

Methods: This retrospective study aimed to evaluate hearing loss in patients with locally advanced NPC treated with carboplatin or cisplatin-based iCRT. Bone conduction hearing thresholds were measured before treatment and at 1 week, 3-6 months and 12-18 months following treatment. Changes in hearing loss were assessed using bone conduction threshold values, threshold shifts from baseline, as well as the Common Terminology Criteria for Adverse Events (CTCAE) grading system.

Result: A total of 156 ears were examined. After iCRT, hearing loss was observed immediately after the conclusion of treatment, peaking at 3-6 months and partially recovering at 12-18 months. At high frequencies, the shifts in hearing thresholds were more pronounced in the cisplatin group compared to the carboplatin group 3-6 months after treatment (p = 0.005), with median hearing threshold shifts of 15 (5.30) dB and 10 (0.15) dB respectively. However, no significant difference was observed at the end of the follow-up period. Similarly, a statistically significant difference in CTCAE scores was observed between the two groups only at 3-6 months following treatment (p = 0.047); patients in the cisplatin group experienced poorer hearing outcomes.

Conclusion: In patients with NPC treated with iCRT, cisplatin is associated with a slightly higher incidence of early high-frequency hearing loss compared to carboplatin. However, this difference diminishes during the mid-term follow-up period, making the substitution of carboplatin unnecessary.