Background: Adult T-cell leukemia/lymphoma (ATL) is a malignancy of mature T-cells occurring in patients infected with the human T-cell lymphotropic virus-I. These patients frequently develop a variety of infections throughout their disease course.
Methods: Charts and autopsy reports were reviewed for 41 patients with ATL with follow-up varying from 2 to 120 months. Infectious episodes were identified and documented. Analyses of humoral and cell-mediated immunity were performed. Cell-mediated immunity was assessed in vivo with the Merieux multitest skin test panel. Humoral immunity was assessed by quantitative immunoglobulin levels, by determining human antimouse antibody after murine monoclonal antibody infusion and by an in vitro immunoglobulin biosynthesis coculture system.
Results: A total of 112 infectious episodes were documented. Fifty-seven serious infections were identified. The incidence of total infections was 1.40/patient-year and for serious infections was 0.71/patient-year. The mean serum IgG and IgA levels were within normal range, the mean IgM level was at the lower limit of normal. Peripheral blood mononuclear cells from all patients studied failed to make meaningful amounts of IgG, M, or A when activated. Peripheral blood mononuclear cells of all of the 13 patients studied suppressed production of immunoglobulin by cocultured normal PBMC. Twenty-three of the 27 patients tested were anergic.
Conclusions: ATL is a profoundly immunosuppressing malignancy. This is manifested by an extremely high incidence of infectious episodes/patient-year. The incidence of infection appears to be greater than for mycosis fungoides, Hodgkin's lymphoma and non-Hodgkin's lymphoma.