IL6 and neoplasm: As mentioned above, this tumor-related cavitary fluid environment has all the inflammatory components of benign effusions (IL-6, sIL-6Rα, CCL2, CXCL10, TGFβ, CCL22, IL-8, IL-5 Figure 1), but includes additional tumor and endothelial growth factors, as well as a blunted effector cytokine response (IFNα2) that is not seen in physiologic cavitary fluid or benign effusions.