To determine the association between HLA class II alleles and the probability of developing cancer in patients with autoimmune rheumatic diseases. MATERIAL AND METHODS; A matched case control study was conducted in which patients with autoimmune rheumatic disease who later developed malignancy (solid or lymphoproliferative) were compared with matched controls suffering from the same auto-immune rheumatic disease and with similar disease duration. The rheumatic diseases included rheumatoid arthritis, systemic lupus erythematosus, primary Sjögren syndrome, dermatomyositis-polymyositis, and systemic sclerosis. HLA-DR typing was performed by sequence-specific primers after DNA amplification by PCR (PCR-SSP). Statistical analysis was conducted by conditional logistic regression.
HLA-DRBI*02 and DRBI*03 were found to be significantly associated with the probability for developing cancer (OR = 5.2 and 4.9, respectively), independent of family history of rheumatoid arthritis and cancer, recurrent sore throat, alopecia, and clinical activity of rheumatoid arthritis.
The results suggest an association between HLA class II alleles with the probability of developing a malignant neoplasm in patients suffering from an autoimmune rheumatic disease.