Patterns of hearing loss resulting from cis-platinum therapy.

The purpose of this study was to provide a clinically useful classification of the hearing loss that occurs with chemotherapy using cis-diamminedichloroplatinum (cis-platinum). Serial audiometric testing was performed on 66 patients who underwent cis-platinum chemotherapy (2 to 6 courses, 100 mg/m2). Subsequent hearing losses were classified according to (1) whether hearing loss occurred after the first or second course of chemotherapy, (2) the magnitude of loss, and (3) the frequencies affected. Of 39 patients who could be classified, 21 (54%) had no loss or mild loss, 14 (36%) had early loss, and 4 (10%) had late loss. Different patterns of hearing loss were observed. The observation that different patterns of hearing loss occur implies that different mechanisms of hearing loss exist. Some mechanisms must be more important in different patients. Our data are important with regard to continuation of chemotherapy treatment after hearing loss occurs. Most significant hearing loss (90%) occurred early or not at all. If early hearing loss occurred and treatment was continued, the speech frequencies were eventually affected in 71% of patients. Recognition of the patterns of hearing loss are important considerations when discontinuation of therapy is being considered.