RESUMO
Idiopathic granulomatous mastitis is a rare inflammatory breast disease of unknown etiology. It manifests as breast mass of 6 cm on average (range 2-10 cm), often in upper outer quadrant of left breast, in another quadrant, right or bilateral breast. Clinical diagnosis by ultrasound or mammography and fine needle aspiration confuses with carcinoma; histopathology (gold standard) confirm the diagnosis after ruling out causes of granulomatous inflammation, mainly tuberculosis. Steroid treatment achieve complete remission, but adverse reactions and relapses after the descent and suspension. Methotrexate or azathioprine is added from the start to maintain remission. We report three cases of idiopathic granulomatous mastitis diagnosis and treatment based on prednisone until clinical improvement and methotrexate as maintenance therapy. Complete remission was obtained in three patients. The rheumatologist knows and handles autoimmune/inflammatory with these drugs, therefore, is suggested the multidisciplinary treatment of this disease with oncologists and gynecologists.