Some aspects of cell-mediated hypersensitivity in patients with melanoma.

Cell-mediated hypersensitivity in 64 patients with melanoma was assessed by delayed-type skin reactivity to dinitrochlorobenzine (DNCB) and tubercullin as well as by lymphocyte enumerations. The immunological status of the patients was correlated with their clinical stage. The mean absolute and percentage counts of E rosette forming cells were lower in patients than in normal controls. Patients with distant metastases showed lower levels of E rosette forming cells than the patients with localized disease. No differences were found in number of EAC rosette forming cells between melanoma patients and controls. The mean absolute and percentage counts of null cells in melanoma patients in stages II and III were significantly higher than those in controls. Melanoma patients showed reduced skin reactivity to DNCB and normal reactivity to tuberculin. Patients with positive DNCB reactivity showed significantly higher total lymphocyte counts and higher percentages of E rosette forming lymphocytes than patients unreactive to DNCB.