Recombinant interferon alpha-2a in combination with dacarbazine in the treatment of metastatic malignant melanoma: analysis of long-term responding patients

IL-2-mediated augmentation of NK-cell activity and activation antigen expression on NK- and T-cell subsets in patients with metastatic melanoma treated with interferon-alpha and DTIC

Considering that well-defined and comprehensive immunological monitoring is the basis for the evaluation of the obtained immunmodulatory effects, we evaluated NK-cell activity, the number of CD3+ CD4+, CD3+ CD8+ T cells and CD16+ CD56+ NK cells, as well as the expression of activation antigens, CD69, CD38 and HLA-DR on CD56+ NK cells, CD8+ and CD3+ T cells, simultaneously with IL-2 and TNF-alpha production, during chemoimmunotherapy with dacarbazine (DTIC) and interferon-alpha (IFN-alpha) in 39 patients with metastatic melanoma. In the first cycle of therapy, there was a significant rise in NK-cell activity, CD4+ T helper cell number, CD4/CD8 T-cell ratio, and the expression of activation antigens CD69 and CD38, on NK and T cells, respectively. However, in the following cycles there was a significant increase only in activation antigens without an increase in the percent or activity of NK cells. The early, but transient, immunopotentiation, present only in the first cycle of combined DTIC and IFN-alpha therapy, suggests that, in spite of increased IL-2 level, associated with augmented NK-cell activity, this therapy has a limited effect probably owing to the adverse effect of persistently high level of TNF-alpha in metastatic disease.

Cytokine therapy of malignant melanoma

Melanoma is a malignant neoplasia of melanocyte origin appearing mainly in the skin. About one third of all melanomas detected disseminate, with the metastatic spread occurring either via lymphatic or blood vessels. In the treatment of advanced melanoma the conventional chemotherapy or radiotherapy has not been very successful. Melanoma is known to have immunologically provocative features. In recent years immunological therapies, mainly cytokines, have been applied in the treatment of melanoma. The most widely used cytokines are Interferons and interleukin-2. These agents are used either alone or in combination with each other or with chemotherapeutics. Interferon and interleukin-2 therapies have yielded response rates of 15-20% on average, whereas combinations of immunotherapy and chemotherapy offer response rates as high as 50-60%. Unfortunately, average survival of patients with disseminated melanoma has been short, from 6 to 12 months. The immunotherapy approach has yielded some long-term responses and probably even a cure for a small proportion of patients. Understanding of basic mechanisms of tumour destruction by cytokines and new agents coming into clinical use will undoubtedly further improve treatment results.

Perspectives of cytokine treatment in malignant skin tumors

Cytokines have been tested in the treatment of different skin cancers during the last decade, and treatment schedules have been established or proposed for several malignant skin tumors. Preferentially, the interferons and interleukin-2 were found to be effective in treating skin cancers. Interferons alpha and beta have been approved for the treatment of human immunodeficiency virus (HIV)-associated Kaposi's sarcoma, cutaneous T cell lymphoma, and malignant melanoma in several countries. Interferon alpha was found to be most effective in cutaneous T cell lymphoma with 40%-60% overall responses. When combining interferon alpha with psoralens and ultraviolet A (PUVA) or with retinoids, even higher response rates up to 60%-90% were reported, and long-term remissions have been described. A considerable activity of interferon alpha was found in HIV-associated Kaposi's sarcoma with response rates of 30%-50%. The effectiveness of Kaposi's sarcoma's treatment was further improved by combining interferon alpha and zidovudine. Responses to interferon alpha in metastatic malignant melanoma are rather seldom (10%-15%), but a stabilization of the disease with prolonged survival was reported after interferon alpha treatment. Additionally, interleukin-2 was found to be active in metastatic melanoma, with overall response rates of about 20%, and both biological agents were found to have an additive efficacy in combination. Several combined regimens of interferon alpha, interleukin-2, and polychemotherapy have been described in metastatic melanoma, and overall response rates higher than 50% were found with these combined treatment modalities. Interferon alpha and beta were also intralesionally injected into basal cell carcinomas and other epithelial skin cancers, and complete responses were found in more than 80% of tumors treated. Local applications of interferons and interleukin-2 were likewise found to be effective in the treatment of cutaneous melanoma metastases and cutaneous manifestations of Kaposi's sarcoma. Cytokines and their combination with other treatment modalities has greatly enriched the treatment facilities in malignant skin tumors during recent years, and additional new cytokines will be introduced in skin cancer treatment in near future.

A phase II study of combined administration of dacarbazine and carboplatin with home therapy of recombinant interleukin-2 and interferon-alpha 2a in patients with advanced malignant melanoma

Chemotherapy and interleukin-2 (IL-2) and/or interferon alpha (IFN alpha) produce objective responses in a proportion of patients with advanced malignant melanoma. The duration of response to chemotherapy is usually less than 4 months, and immunotherapy has resulted in long-lasting remissions in a small number of patients with metastatic melanoma. The current study was conducted to improve the antitumor efficacy and the interactions between recombinant (r) IL-2, rIFN alpha 2a and chemotherapy. A total of 16 evaluable patients with metastatic malignant melanoma were entered into a phase-II study designed to assess the response rate and therapeutic efficacy of dacarbazine and carboplatin followed by rIL-2 and rIFN alpha 2a. Patients received 750 mg/m2 dacarbazine with 400 mg/m2 carboplatin each by intravenous bolus on days 1 and 22. Recombinant IL-2 and IFN alpha 2a were administered on an outpatient basis (home therapy) subcutaneously for 6 consecutive weeks: 4.8 x 10(6) IU/m2 rIL-2 daily, 5 days a week; 6.0 x 10(6) IU/m2 rIFN alpha 2a thrice weekly. There were responses in 6 of the 16 enrolled patients with an overall response rate of 37.5% (95% confidence interval: 14%-61%). All responding patients had partial responses. The median survival time of the responding patients was significantly better than that of patients with progressive and stable disease (P = 0.03). The median duration of response was 11 months (range 2-24 months). Responses in lung, liver, soft tissue and lymph-node sites were noted.