Cisplatin/carboplatin cross-resistance in ovarian cancer.

Forty-six patients who were treated with cisplatin or carboplatin for ovarian cancer developed resistant disease (no change in measurable disease or progressive disease) and 'crossed over' to the other platinum compound. Three patients (6.5%) responded to this second treatment but these patients had no survival advantage compared to the non-responders. One responder had progressive disease on cisplatin before crossing over to carboplatin.