Malignancies in autoimmune rheumatic diseases - a mini-review.

Paraneoplastic symptoms, caused by a malignancy, but not directly related to invasion by the tumor or its metastases, are the result of a wide variety of tumor-derived biologic mediators like hormones, peptides, antibodies, cytotoxic lymphocytes, autocrine and paracrine mediators. Systemic inflammatory rheumatic diseases, such as rheumatoid arthritis, systemic lupus erythematosus, scleroderma or dermatomyositis, may increase the risk for the development of malignancies, predominantly lymphoproliferative disorders. Immunosuppressive drugs and biological agents may also be carcinogenic. However, sustained inflammatory activity seems to be the primary risk factor for malignancies in autoimmune diseases. Tumor-associated antigens may be produced by inflammatory cells and their production may be increased in rheumatoid arthritis and other autoimmune diseases.