Reduced lymphocyte subpopulations in patients with advanced or disseminated melanoma

Background: Studies have revealed many features of lymphocyte behavior in patients with malignant melanoma, but there are conflicting results. Objective: The aim of this study was to measure with easily reproducible assays the circulating lymphocytes and other immunologic aspects in 33 patients with advanced or disseminated malignant melanoma (MM). Methods: The following variables were measured: circulating monocytes; total lymphocytes; B (CD19) and T-cell subpopulations; CD3, CD4, and CD8, natural killer cells (anti-Leu-7 + or CD57 and anti-Leu-11 + or CD16) (cytofluorimetry); plasma levels of IgG, IgA, IgM, and IgE; complement fractions 3, 4, and 1Q; antibodies against foreign microorganisms (AaM) (adeno, herpes simplex, herpes zoster, measles, parotitis, cytomegalo, Epstein-Barr, and rubella viruses) and Toxoplasma; and cutaneous delayed hypersensitivity (CDH) to recall antigens (tetanus, diphtheria, Streptococcus, tuberculin, Proteus, Trichophyton, and Candida). We also studied 9 6 healthy persons, matched for age and geographic location, who were tested on the same days as the patients. Results: In MM the number of total lymphocytes and subsets CD19, CD3, CD4, and CD8 was decreased from 25% to 40% ( p < 0.001). The CD4/CD8 ratio increased (22%, p < 0.005) because of the relatively greater decrease of CD8. The CD57 and CD16 cells (expression of natural killer lymphocytes) were consistently reduced (30%; p < 0.002 to p < 0.003). C3 serum level was increased (30%; p < 0.001). Immunoglobulins, CDH, AaM, and all other tests were the same in the two groups. Conclusion: The single most important result seems to be a reduction of CD57 and CD16 cells in patients with advanced MM.