Association between autoantibodies in systemic sclerosis and cancer in a national registry.

Abstract

OBJECTIVE\nA close temporal relationship between systemic sclerosis (SSc) onset and cancer has been reported in anti-RNA polymerase III-positive patients. We investigated the association between cancer and other SSc autoantibodies in a national SSc registry.\n\n\nMETHODS\nSSc patients enrolled in the Canadian Scleroderma Research Group registry from 2004 to 2019 were characterized according to autoantibodies to centromere, topoisomerase I/Scl70, RNA polymerase III, fibrillarin, Th/To (hPOP1), PM/Scl, Ku, NOR90, Ro52/TRIM21 and U1RNP. Logistic regression was used to examine the association between a close cancer-SSc interval and autoantibody status, adjusted for age, sex, race and smoking history.\n\n\nRESULTS\nOf 1698 SSc patients, 1481 (87%) had available autoantibody data. Cancer was diagnosed within 2, 3 and 5\u2009years of the first non-Raynaud manifestation in 1.3%, 2.1% and 3.5% of patients. The most frequent cancers diagnosed within 2\u2009years were breast (33%), gynaecological (19%) and haematological (14%) cancers. The risk of cancer within 2\u2009years was increased among anti-topoisomerase I (OR 3.43, 95% CI 1.04-10.05) and anti-U1-RNP-positive patients (OR 5.54, 95% CI 1.16-20.40), but not with anti-RNA polymerase III. None of the anti-fibrillarin, Th/To, PM/Scl, Ku and NOR90-positive patients had cancer within 2\u2009years. Patients with anti-centromere or none of the tested autoantibodies had numerically lower risks of developing cancer within two years.\n\n\nCONCLUSION\nSynchronous cancer was rare in this large cohort of predominantly female and White SSc patients. The risk of cancer within 2\u2009years was increased among anti-topoisomerase I and anti-U1-RNP-positive patients. Screening strategies guided by autoantibodies require further careful consideration.