Thirteen consecutive patients with inoperable recurrent malignant melanoma were treated by immunochemotherapy with the use of chlorambucil noncovalently bound to goat or rabbit antihuman melanoma globulins. The next consecutive 11 patients fulfilling the criteria for admission into this study were treated with chemotherapy only, i.e., dimethyltriazenoimidazole carboxamide (DTIC). Follow-up was for a minimum of 29 months or until death. Two patients showing an objective response to immunochemotherapy had disease confined to lymph nodes and cutaneous sites; 5 others showed stabilization of cutaneous, nodal, and visceral disease, and 6 patients showed progression of their disease. The median survival of the responders and stabilizers was 20 months, but only 3.5 months for patients with disease progression. None of the 11 patients treated with OTIC had objective tumor regression, and all died within 11 months of the start of treatment with a median survival of 3 months. Immunochemotherapy significantly prolonged the survival compared to that in the OTIC-treated group (P<0.05). No hematologic or renal toxicity was detected after immunochemotherapy, but 2 patients in this group developed anaphylactic reactions. Skin reactivity tests to dinitrochlorobenzene and purified protein derivative were of no prognostic value.