Clinical evaluation of interferons in malignant melanoma. The evaluation of interferons in the treatment of malignant melanoma has been mainly in the treatment of advanced disease using interferons as the sole agent or in combination with other agents. Studies of the value of interferons as adjuvant therapy in high-risk primary melanoma patients are necessary, but no results have been published to date. Human interferon alpha produces low response rates as a sole agent, but in combination with cimetidine, a 30% response rate has been achieved. Recombinant alpha interferons give responses of 15%-20% in advanced melanomas, and combination with cimetidine does not enhance the response rate. Recombinant alpha interferons have been used in combination with other interferons, cimetidine, monoclonal antibodies, and cytotoxics, with either no or small improvement in response rates. DTIC with recombinant interferon alpha-2a has been shown to produce objective response rates of 26%, with low toxicity and maintenance of quality of life. A randomized trial with DTIC as the sole agent, compared with combination treatment, is being conducted to determine the significance of this finding. 