Cutaneous curiosity: axillary apocrine carcinoma.

A middle-aged male patient in his 40s presented with a 6-month history of a progressively enlarging, painless right axillary mass measuring 7 cm × 5 cm, fixed to the skin. MRI revealed a lobulated dermal lesion with increased vascularity and deep pectoral lymphadenopathy. The biopsy showed nodular arrangements of polygonal tumour cells with eosinophilic cytoplasm. Immunohistochemistry (IHC) was positive for carcinoembryonic antigen and gross cystic disease fluid protein-15, and negative for markers ruling out metastatic disease, confirming primary cutaneous apocrine carcinoma. The patient underwent wide local excision with level I and II axillary lymph node dissection and dorsal scapular flap reconstruction. Histology revealed one metastatic lymph node and tumour positivity for androgen receptor, oestrogen receptor, progesterone receptor and GATA-3. Postoperative radiotherapy was administered. At 6 months, the patient remained recurrence-free. This case highlights the diagnostic challenge of apocrine carcinoma in young patients and underscores the importance of thorough IHC and aggressive multimodal treatment for optimal outcomes.