Circulating autoantibodies in patients with fibrocystic disease of the breast.

Antinuclear, parietal-cell, smooth-muscle, mitochondrial, and adrenal antibodies were determined in the blood serum of 110 patients with fibrocystic disease of the breast and of 102 healthy blood donors by indirect immunofluorescence. Thirty-eight percent of the patients had detectable autoantibodies compared to 16% of the controls (P less than 0.001). Significant differences were found in the incidence of parietal-cell and smooth-muscle autoantibodies between the patients and controls. In addition, more than one autoantibody was detected in the serum of a significantly larger number of patients than controls. The findings indicate that an immunologic mechanism is involved in the pathogenesis of fibrocystic disease of the breast.