Increased levels of serum and/or tumor IL-6 are also seen in a number of malignant conditions, both haematopoietic malignancies and solid tumors including breast, cervical, esophageal, head-and-neck, ovarian, prostate, colorectal, pancreatic, hepatocellular, gall bladder, non-small-cell lung cancer and multiple myeloma, reflecting the immunological involvement in cancer. Here, IL6 is linked to plasma cell myeloma.