Abstract
BACKGROUND: Breast tuberculosis, also known as tuberculous mastitis, is an extremely rare form of tuberculosis. It accounts for <0.1% of all breast diseases and <2% of all cases of tuberculosis. It is often misdiagnosed as breast cancer, which can potentially lead to a delayed diagnosis. CASE PRESENTATION: A 69-year-old Japanese woman presented with a tumor-mimicking lesion in her right breast, followed by intractable mastitis with a fistula formation. The time until the correct diagnosis of tuberculosis of the breast and sternal bone was 14 months. CONCLUSIONS: Although rare, it is important to recognize that tuberculous mastitis can present as refractory abscesses/mastitis or mass lesions that mimic carcinomas in women of reproductive age and elderly people. Breast tuberculosis should always be considered in the differential diagnoses, particularly in patients with a history of tuberculosis and those living in areas where tuberculosis is endemic.