Isolated bilateral breast tuberculosis mimicking carcinoma: a rare case report from Pakistan

Breast tuberculosis (BTB) is a highly unusual form of extrapulmonary tuberculosis, accounting for less than 1% of all breast tumors worldwide. The disease poses a serious diagnostic problem because of its clinical and radiological resemblance to breast cancer. Bilateral involvement is highly uncommon and has been reported in only 3% of BTB cases. We report an unusual case of bilateral primary BTB mimicking carcinoma in a perimenopausal woman from Pakistan.

A 42-year-old perimenopausal housewife presented with bilateral breast lumps with asymmetrical progression for 10 months. On the right side, there was an inflammatory and painful lump measuring 6 × 5 cm with skin thickening (peau d'orange) and retraction of the nipple. On the left side, there was a painless, mobile lump measuring 3 × 4 cm. Bilateral suspicious parenchymal densities were observed on mammography, with right BI-RADS 5 and left BI-RADS 4A findings. All microbiological investigations, including acid-fast bacilli, Gram staining, and cultures, were negative. Biopsies of the bilateral masses confirmed, histopathologically, benign mammary parenchyma with prominent central necrotizing granulomatous inflammation, and a diagnosis of tuberculous mastitis was made. Unfortunately, advanced molecular testing (GeneXpert MTB/RIF) could not be performed because of financial considerations. She received ATT for 6 months and required surgical debridement during the sixth week of her treatment due to paradoxical abscess and sinus formation. Healing was complete without recurrence for up to 1.5 years.

BTB is an important pitfall that may mimic advanced breast carcinoma and idiopathic granulomatous mastitis. In countries where tuberculosis is endemic, a strong index of suspicion for BTB is essential when encountering atypical or bilateral breast masses. Histopathology is indispensable for confirming the diagnosis and avoiding inappropriate oncological management, especially in areas where advanced diagnostics for TB are not available.