Granulomatous lobular mastitis: a rare chronic inflammatory disease of the breast which can mimic breast carcinoma.

Granulomatous lobular mastitis is a rare chronic inflammatory disease of the breast. The differential diagnosis with malign breast disease is often not easy. In most cases a surgical biopsy is needed for correct diagnosis. Idiopathic granulomatous mastitis is an exclusion diagnosis, based on the demonstration of a characteristic histological pattern, combined with the exclusion of other possible causes of granulomatous breast lesions. There is still no generally accepted optimal treatment. If surgery forms part of the treatment, a conservative approach seems to be adequate in most cases. Another option is a long-term steroid treatment. It is mandatory to exclude infectious causes of granulomatous mastitis before corticoid therapy is started.