Serum Interleukin-6 Levels in Adult Acute Myelogenous Leukemia: Relationship with Disease Characteristics and Outcome

Serum interleukin-6 (IL-6) levels were measured in 58 adult patients with newly diagnosed acute myelogenous leukemia (AML) using an ELISA method in order to find potential clinical correlations. Detectable average levels were 57 +/- 68 pg/ml and 52 patients (90%) had higher cytokine levels than normal donors. IL-6 levels (115 +/- 102 pg/ml versus 36 +/- 40 pg/ml, p = 0.0001) were higher in patients with fever of apparently non infectious origin, and higher levels were associated with higher percentage of blasts in the peripheral blood (R = 0.29, p = 0.04) and in the bone marrow (R = 0.39, p = 0.003), elevated serum LDH level (R = 0.36, p = 0.01), hyperbilirubinemia (R = 0.36, p = 0.008), elevated serum GGT level (R = 0.46, p = 0.003), and elevated serum GOT (R = 0.36, p = 0.008) and GPT levels (R = 0.44, p = 0.004). Highest IL-6 levels were observed in FAB M1 (86 +/- 112 pg/ml), M3 (73 +/- 69 pg/ml), and M6 (92 +/- 60 pg/ml) AML subtypes. Serum IL-6 levels in AML might be related to both non specific inflammatory reactions and the specific biology of the disease.