Anticentromere antibody as a risk factor for cancer in patients with systemic sclerosis

This study has estimated the cancer risk among patients with systemic sclerosis (SSc) using a population-based analysis. Using the inpatient and outpatient registries for patients at Kyushu University Hospital between 1982 and 1996, standardised incidence rates (SIRs) (ratio of observed-to-expected cancers) were calculated in 43 patients with SSc, 24 patients with polymyositis (PM) and 17 patients with dermatomyositis (DM). Risk factors predisposing to cancers were also investigated in the SSc patients. Compared with the Japanese general population, the SIR for developing cancer in SSc patients was 5.1 (95% confidence interval (CI), 1.7-10.8), while the SIRs for cancer in the PM and DM groups were 4.7 (95% CI, 1.5-10.3) and 61.2 (95% CI, 46.8-77.6), respectively. A statistically significant risk factor for cancers in the SSc patients was positivity for anticentromere antibody (ACA) (p<0.05), while the erythrocyte sedimentation rate, serum lactate dehydrogenase concentration, serum gamma-globulin concentration, titre of antinuclear antibody and positivity for antitopoisomerase I antibody were not associated with cancer in SSc. Our population-based study confirms the increased risk of cancer among patients with SSc in Japan and provides new evidence that positivity for ACA should be considered as a risk factor for cancer in future monitoring of patients.