Current experience with high-dose carboplatin therapy.

Carboplatin is well suited to dose escalation because its major dose-limiting toxicity is myelosuppression when given in 1,200 mg/m2 doses without marrow support. Repeated 800 mg/m2 doses can be given in an investigational setting. With autologous bone marrow rescue the maximum tolerated single-agent dose is approximately 1.8 to 2 g/m2, with dose-limiting toxicities being hepatitis, renal dysfunction, and ototoxicity. Combinations of carboplatin with other agents plus bone marrow rescue are now being investigated in germ cell tumors, ovarian cancer, breast cancer, and small cell lung cancer. High-dose carboplatin plus etoposide combinations are being evaluated with colony-plus stimulating factors in an effort to ameliorate myelosuppression. Future high-dose carboplatin studies could be designed with more predictable toxicity, using an assessment of carboplatin renal clearance. Carboplatin is an important new drug warranting further investigation at escalated doses.