Cytological Features of Granulomatous Mastitis- A study of ten cases

Introduction: Granulomatous mastitis is a rare benign disease, the exact cause of which is still unknown. It usually presents as a mass which may simulate carcinoma. Many patients are put on long term antibiotics because of breast abscess suspicion, but are not cured. This disease usually affects women of child-bearing age with a history of oral contraceptive use. Most cases have been reported in third decade. In previous studies most of cases of idiopathic granulomatous mastitis were within six years of pregnancy. There are two types of granulomatous mastitis, specific and idiopathic. Aim: To study cytological features of granulomatous mastitis, the age group involved and how to differentiate it from malignancy to prevent unnecessary mastectomies. Method: FNAC was performed with 22G needle. Slides prepared were stained with leishman stain. Special stains like Zeihl Nelson stain and Periodic Acid Schiffs were done to rule out mycobacterium and fungal etiology. Result: Cytological features of noncaseating granuloma along with plenty of polymorphs in the background is suggestive of granulomatous mastitis. History of lactation and oral contraceptives along with special tests further aids in its diagnosis. Conclusion: In this study of ten cases we describe the importance of cytology in diagnosis of granulomatous mastitis which helps us to prevent unnecessary mastectomies. GM is essentially a diagnosis of exclusion that is by excluding other causes of chronic inflammation. Infective causes such as tuberculosis should always be ruled out before stating treatment with steroid.