High frequency audiometry in prospective clinical research of ototoxicity due to platinum derivatives

The results of clinical use of routine high frequency audiometry in monitoring the ototoxic side effects of platinum and its derivatives are described in this prospective study. After demonstrating the reproducibility of the technique, we discuss the first results of an analysis of ototoxic side effects in 75 patients (150 ears). Significant differences in the pattern of hearing loss were registered for the different platinum treatment groups (cisplatin 20 mg/m2, cisplatin 50 mg/m2, and carboplatin 350 mg/m2). In the groups receiving cisplatin 50 mg/m2 and carboplatin 350 mg/m2, 42% and 25%, respectively, of the investigated ears proved to be undamaged, versus 9% undamaged in the group receiving cisplatin 20 mg/m2 (p less than .01). Ototoxic hearing loss started mainly (46% to 70%) in the higher frequencies (10,000 to 18,000 Hz) and developed into a broader-range hearing loss (1,000 to 18,000 Hz) during treatment in 13% to 43% (p less than .01). The onset of hearing damage was influenced by the patient's age (p less than .001) and the existence of a troubled otologic history (p less than .05). The study demonstrates the important role of high frequency audiometry in early detection and monitoring of ototoxic damage.