Background: Based on prior experience with dacarbazine (DTIC) and an outpatient interleukin-2 (IL-2) regimen, the current study was conducted to improve the antitumor efficacy and assess the immunologic interactions between chemotherapy and IL-2.
Methods: Thirty-two patients were registered onto a treatment program, which included DTIC 750 mg/m2 with cisplatin 100 mg/m2, each by intravenous bolus on day 1. Recombinant IL-2 was administered on an outpatient basis intravenously by 15-30-minute infusion (24.0 x 10(6) IU/m2) daily on days 12-16 and 19-23 of a 28-day cycle for three cycles and then every 42 days for responding patients.
Results: There were responses in 13 of the 32 registered patients (41% response rate), including five complete and eight partial remissions. Responses in the liver, lung, spleen, lymph nodes, and soft tissue sites were noted. The median duration of response was 8.0 months (range, 3.0-20.0+ months), and the overall median survival duration was 10.2 months. Three patients (9%) are alive, free of disease, without any treatment at 32.0+, 36.0+, and 42.0+ months after initiation of treatment. Only minor nephrotoxicity was observed, and treatment delays were rare.
Conclusions: Additional chemotherapeutic, hormonal, or biologic agents may be added to enhance efficacy further if they have toxicities that do not overlap.