Platinum compound-related ototoxicity in children - Long-term follow-up reveals continuous worsening of hearing loss

Objectives: The Purpose of this study was to evaluate the severity of hearing loss after cisplatin and/or carboplatin treatment in young children and to analyze its evolution and its relation to different therapy schedules. Methods: One hundred twenty patients treated in the Pediatrics Departinent at the Institut Gustave-Roussy from 1987 to 1997 for neuroblastoma, osteosarcoma, hepatoblastoma,or germ cell tumors were analyzed. Median age at diagnosis was 2.6 (range 0-17) years. Median follow-up was 7 (1-13) years. Chemotherapy regimens contained cisplatin and/or carboplatin. Three patients also received highdose carboplatin. Cisplatin was administered at a dose of 200 mg/m(2)/course in 72% of cases. The median cumulative dose was 400 mg/m(2) for cisplatin and 1,600 mg/m(2) for carboplatin. Hearing loss of grade 2 or above. according to Brock's grading scale, was revealed with pure tone audiometry and behavioral techniques. Results: Carboplatin alone was not ototoxic. Deterioration of hearing of grade 2 or above was observed in 37% of patients treated with cisplatin and 43% of patients treated with cisplatin Plus Carboplatin (P = NS). Fifteen percent of patients experienced grade 3 or 4 ototoxicity. Ototoxicity was most often observed after a total cisplatin dose of at least 400 mg/m(2). No improvement was observed with time; on the contrary. worsening or progression of hearing loss at lower frequencies was detected doting follow-up. Only 5% Of audiograms showed toxicity of at least grade 2 before the end of therapy; in contrast, this level was observed in 11% of early post-therapy evaluations and in 44% after more than 2 years Of follow-up. Conclusions: Children treated with cisplatin at cumulative doses approaching 400 mg/m(2) require long-term surveillance to avoid overlooking hearing deficits. Carboplatin, at a standard dose, does not appear to be a significant risk factor for ototoxicity even in patients who have already been treated with cisplatin.