Autoantibodies in patients with systemic sclerosis and cancer: A case-control study

Objective. To determine the prevalence of specific autoantibodies in a cohort of patients with systemic sclerosis (SSc) and a diagnosis of cancer, and to compare it to that in a group of patients with SSc who were never diagnosed with cancer. Methods. From 769 patients with SSc followed at our center over the past 15 years, 77 had a diagnosis of cancer. The results of autoantibody studies in this group were compared to those from 159 SSc patients without cancer randomly selected from the rest of the patient population using chisquare test for independence and the null hypothesis for 2 population proportions. Results. There was no statistically significant difference between the proportions of patients with positive autoantibodies between the 2 groups, except that a higher prevalence of autoantibodies with a nucleolar immunofluorescence pattern was observed in the group of patients who were never diagnosed with cancer (p < 0.01). Conclusion. In contrast to previous studies, in our case-control study we were not able to detect a significant difference in autoantibody frequency or patterns among SSc patients with and without a diagnosis of cancer. These results refute the conclusion made previously that certain autoantibodies may represent risk factors for the development of cancer in patients with SSc.