Immune responsiveness and immunotherapy in patients with metastatic melanoma
The results in 120 patients with melanoma that the authors studied and treated by immunotherapy are described. Serum immunoglobulin levels in patients with malignant melanoma revealed normal IgA and IgG levels and only infrequent IgM values were below the normal range. Serologic evaluation for tumor specific antibody revealed positive response in 31 of the first 70 patients studied. 17 of the 31 were positive by mixed agglutination, 30 of 31 by cytotoxicity and 20 of 31 by complement fixation. Almost without exception these patients with melanoma demonstrated either hyporesponsive skin test reactivity or anergy. After completing the immunotherapy regimen several interesting things were noted in the response of the patient's lymphocytes in culture. Prior to treatment, the only normal response in culture was to phytohemagglutinin (PHA). However, after completion of the regimen the stimulation index for PHA, unrelated lymphocytes, BCG and unrelated fibroblasts were all within the normal range. The most interesting finding was the response of the patient's autologous lymphocytes to the autologous melanoma cells that had been x irradiated. The mean stimulation index was 8.5 being the highest stimulation that the authors have seen by autochthonous tumor cells. Cellular immunity evaluation in 62 patients rested revealed that 43 of 62 were positive for cellular immunity after completing the immunotherapy regimen. The degree of lysis was increased in most patients by the regimen. All 19 patients without cellular immunity had diffuse disease and progressed to death. Serum blocking factor evaluation in the 62 patients tested demonstrated that 21 of 62 patients were positive for serum blocking factors. This, however, did not correlate with the clinical course. Blocking factor was not present in 20 patients that had progression of disease to death. Overall evaluation at the present time reveals that in the first 120 patients evaluated, 34% have expired secondary to their melanoma process, 43% continue to have the disease and 23% have remained free of disease. The study has been in progress for approximately 3.5 yr and some patients have remained well for the entire period. This followup period obviously is too short to make any firm statements about the immonotherapy regimen. Suffice it to say that this study revealed hyporesponsiveness to delayed hypersensitivity skin tests in two thirds of patients with melanoma and low IgM levels in approximately 20%.
