Changes in circulating angiogenic and inflammatory factors during therapy with lenalidomide. Peripheral blood was collected from patients receiving lenalidomide therapy at baseline and after 7 days and 28 days of treatment. Plasma samples from patients with stable disease or no response (SD + NR, gray lines) and partial response or complete response (PR + CR, black lines) were analyzed for the angiogenic factors FGF-basic, VEGF, and IL-8; the inflammatory cytokines IFN-γ, IL-1β, IL-2, IL-6, IL-8, IL-10, and TNF-α; and the soluble cytokine receptors IL-2R and TNF-RI. Longitudinal analysis of SD + NR shows significant changes over time in IL-6, IL-10, IL-2R, and TNF-RI. PR + CR show significant changes over time in FGF-basic, IL-10, and IL-2R. The change in VEGF concentrations was not statistically significant for either group. Plasma concentrations are reported in mean (± SEM) picogram per milliliter.