A Retrospective Study of Idiopathic Granulomatous Mastitis at a Tertiary Care Center

Abstract

BACKGROUND Idiopathic granulomatous mastitis (IGM) is a rare benign chronic inflammatory disease of the breast, which is often difficult to differentiate both clinically and radiologically from infectious aetiologies such as tuberculosis, fungal infections, and also from malignancy, thus posing a diagnostic dilemma. Histopathology is essential to solve the dilemma and make a definitive diagnosis. The aim of this study is analysis of idiopathic granulomatous mastitis and its mimics. METHODS This study was done at Osmania Medical College, over a period of 3 years from 2016 to 2019. 30 cases were analysed. Clinicopathological data like pertinent history, clinical and radiological features, and cytological results, was collected from the medical records. All slides were stained with haematoxylin and eosin. RESULTS A total of 30 cases was studied. The study group included women who were 25 to 45 years old; left breast was most commonly involved. The most common presenting symptom was lump 98 % (n=29) in breast. Mammography revealed skin thickening, parenchymal heterogeneity, irregular mass and focal asymmetric density. Ultrasonography shows ill-defined hypoechoic lesions. On histology, 27 cases (90%) were diagnosed as idiopathic granulomatous mastitis and 3 cases (10%) were diagnosed as tuberculosis granulomatous mastitis. CONCLUSIONS Idiopathic granulomatous mastitis is a benign entity which has varied and nonspecific appearances on ultrasound and mammography and often mimics malignancy and various benign inflammatory conditions of breast. Histopathological examination is necessary to establish diagnosis before deciding upon treatment and also to prevent unnecessary mastectomy.