Serum levels of interleukin-10 in patients with diffuse large cell lymphoma: lack of correlation with prognosis.

Interleukin-10 (IL-10), also known as cytokine synthesis inhibitory factor, has multiple effects on lymphoid development. In addition, it has been previously reported that serum levels of IL-10 correlate with failure-free and overall survival in patients with non-Hodgkin's lymphoma. In this study, we used a sensitive enzyme-linked immunosorbent assay specific for human IL-10 (lower limit of sensitivity, 5 pg/mL) to measure serum levels in 52 newly diagnosed patients with diffuse large cell lymphoma and at least one adverse prognostic feature who were subsequently treated in a uniform way. Lymphoma patients had significantly higher serum levels of IL-10 (median, 7.98 pg/mL; range, < or = 5 to 27,143 pg/mL) than healthy volunteers (N = 50; median, < or = 5 pg/mL; range, < or = 5 to 19.21 pg/mL) (P = .0000012). Individuals with B symptoms had significantly higher serum levels of IL-10 than those without them (P = .03), but there was no correlation between IL-10 levels and any of the other prognostic variables analyzed, including age, lactic dehydrogenase, beta 2-microglobulin levels, performance status, bulky disease, Ann Arbor stage, or International Index score. More importantly, we found no correlation between IL-10 levels and the achievement of complete remission, nor with failure-free survival or overall survival. We conclude that in a uniform population of untreated patients with diffuse large cell lymphoma, serum levels of IL-10 do not appear to have any prognostic value.