Ototoxicity associated with cis-platinum in three chemotherapy multi-drug regimens

Hearing threshold differences postcis-platinum, relative to precis-platinum levels, were studied in 21 men from a Veterans Administration Medical Center. These patients had previously untreated advanced epidermoid cancers of the head and neck. Each patient received one of three drug combinations: (1) cis-platinum, Oncovin, and bleomycin (n = 9); (2) cis-platinum and 5-fluorouracil (n = 7); or (3) cis-platinum and bleomycin (n = 5). Wide variations in prechemotherapy hearing thresholds prevented analysis among various drug combinations. Therefore, the three groups were pooled to compare the thresholds by frequency. The frequencies tested and analyzed were: 250 Hz, 500 Hz, 1000 Hz, 2000 Hz, 4000 Hz, and 8000 Hz. Significant differences were found at 2000 Hz (P less than 0.01) and 8000 Hz (P less than 0.05). Any existing ototoxic effects of cis-platinum may have been overridden by already high prechemotherapy hearing thresholds at 4000 Hz. Since 2000 Hz was most sensitive to the ototoxic effects of cis-platinum it is suggested that this frequency be monitored routinely as a part of standard chemotherapy assessment.