Accessory breast granulomatous mastitis: A case report and mini‑review of the literature

Granulomatous mastitis (GM) is a rare inflammatory condition that primarily affects the breasts, and its occurrence in accessory breast tissue is even rarer. The present report describes the case of a patient with GM in the accessory breast. A 43-year-old female patient presented with a 1-month history of pain in the left axilla and breast. An analysis of her medical and surgical history did not reveal any notable findings, but she had a history of four full-term pregnancies and a cumulative lactation period of 4 years. Upon a clinical examination, a palpable, ill-defined, tender mass was noted along with an accessory breast and nipple in the axilla. The diagnosis was chronic mastitis, and she was treated with oral corticosteroids, amoxicillin, cabergoline and analgesics. Her condition initially improved; however, the symptoms recurred 1 year later. A wide local excision of the left axillary tail was performed. The patient experienced marked improvement post-surgery and remained stable, with no recurrence, at the 1-year follow-up. In addition, in the present study, seven recent cases of GM were included for a brief literature review, involving patients aged 23 to 42 years. Of these cases, 6 cases did not have any notable medical histories. A total of 6 patients had a history of pregnancy, with an average lactation duration of 22.7 months. The right breast was affected in 6 cases. Pain and swelling were the most frequent symptoms. A conservative approach, which included antibiotics, corticosteroids and wound dressing was used for 5 patients. In total, 6 patients achieved recovery. On the whole, the present study demonstrates that accessory breast tissue can develop GM. While corticosteroids may provide favorable short-term results, they do not necessarily prevent recurrence, whereas surgical management may provide more durable long-term outcomes.