Risk and outcome in metastatic malignant melanoma patients receiving DTIC, cisplatin, BCNU and tamoxifen followed by immunotherapy with interleukin 2 and interferon alpha2a

Abstract

Combined chemo-/immunotherapy has shown high objective response rates and a significant though small proportion of long-term complete responders in metastatic malignant melanoma. The purpose of this study was to determine response rates, freedom from treatment failure (FFTF) and overall survival in patients with advanced metastatic malignant melanoma treated with combined chemo-/immunotherapy, and to determine the value of a prognostic model for prediction of treatment outcome, FFTF and survival. Sixty-nine patients with metastatic malignant melanoma received combined chemo-/immunotherapy consisting of up to four cycles of DTIC (220 mg m(-2) i.v. days 1-3), cisplatin (35 mg m(-2) i.v. days 1-3), BCNU (150 mg m(-2) i.v. day 1, cycles 1 and 3 only) and tamoxifen (20 mg orally, daily). Two cycles of chemotherapy were followed by 6 weeks of outpatient immunotherapy with combined interleukin 2 (20 x 10(6) IU m(-2) days 3-5, weeks 1 and 4; 5 x 10(6) IU m(-2) days 1, 3, 5, weeks 2, 3, 5, 6) and interferon-alpha (6 x 10(6) IU m(-2) s.c. day 1, weeks 1 and 4; days 1, 3, 5, weeks 2, 3, 5, 6). All patients were evaluated on an intention-to-treat basis. Of 69 patients entered in the study, seven achieved complete remissions and 20 reached partial remissions with an objective response rate of 39% (95% confidence interval 28-52%). Median survival was 11 months, median FFTF was 5 months. Seven patients achieved ongoing long-term remissions, with maximum survival of 58 + months, and maximum FFTF of 58 + months. By Kaplan-Meier survival analysis and two-proportional Cox regression analysis, pretreatment performance status and serum lactic dehydrogenase were statistically significant and independent predictors of survival; risk groups could be defined as (a) the absence of both or (b) the presence of either one or both of these risk factors. Whereas survival and response were significantly influenced by patient risk, no influence could be demonstrated for FFTF. This combined outpatient chemo-/immunotherapy is feasible and results in objective response rates and survival similar to earlier trials. Pretreatment risk, as defined by serum lactate dehydrogenase (LDH) and performance status, has a significant impact on treatment outcome and patient survival.