Multiple myeloma (MM) is a malignant disease characterized by the clonal proliferation of plasma cells within the bone marrow. Several cytokines have been demonstrated to be involved in the control of growth, progression, and dissemination of MM. We determined serum levels of interleukin-1beta (IL-1beta), soluble interleukin-2 receptor (sIL-2R), interleukin-6 (IL-6), interleukin-8 (IL-8), tumor necrosis factor-alpha (TNF-alpha), and C-reactive protein (CRP) in 14 newly diagnosed MM patients. The median age of the patients was 63.4 +/- 10.8 years and all of the patients were stage III (classified according to the Durie-Salmon classification). The same parameters were measured in 15 healthy controls. In addition, we also examined the effects of vincristine-adriamycin-dexamethasone (VAD) therapy on the same parameters and mediators as well as the relationship among the parameters in the same patient groups. The serum concentrations of TNF-alpha, IL-1beta, sIL-2R, IL-6, IL-8, and CRP (18.6 +/- 3.7 pg/mL, 10.1 +/- 2.8 pg/mL, 730 +/- 220 U/mL, 11.4 +/- 3.3 pg/mL, 23.9 +/- 8.3 pg/mL, and 49.9 +/- 19.5 mg/dL, resp) were significantly higher in newly diagnosed MM patients than in healthy controls (P < .0001). All of the parameters were found to be significantly reduced after chemotherapy. In conclusion, we found that after the VAD therapy, the level of these cytokines which are thought to play an important role in the pathogenesis of MM was significantly suppressed. This is the first study demonstrating strong impact of VAD treatment on circulating mediators of sIL-2R and IL-8 levels parameters.