Accessory breast tissue in axilla masquerading as breast cancer recurrence.

Ectopic or accessory breast tissue is most commonly located in the axilla, though it may be present anywhere along the milk line. Development is hormone dependent, similar to normal breast tissue. These lesions do not warrant any intervention unless they produce discomfort, thus their identification and distinction from other breast pathologies, both benign and malignant, is essential. We report a case with locally advanced breast cancer who presented with an ipsilateral axillary mass following surgery, radiotherapy, and chemotherapy. Subsequent evaluation with excision biopsy showed duct ectasia in axillary breast tissue and the patient was continued on hormone therapy with tamoxifen.