Granulomatous mastitis is a rare inflammatory breast disease. It should be considered in the differential if a patient presents with an inflammatory breast mass.

It usually occurs in young parous women with a recent history of pregnancy or breastfeeding.

Idiopathic granulomatous mastitis was first described by Kessler and Wolloch in 1978.

Other causes of granulomatous mastitis include tuberculosis, sarcoidosis, Wegener's granulomatosis or fungal infection.

Definitive diagnosis is made using histopathology result as clinical findings and imaging studies are non-specific.