Axillary skin malignancy: a rare breast cancer presentation

A rise in incidence and decrease in mortality rates from breast cancer have lead to an increase in prevalence within developed countries. Presentation is classically with a palpable breast tissue mass that may metastasize to bone, lung, liver, brain, lymph nodes, and skin. We describe a delayed diagnosis, in an 80-year-old female patient, where, on 2 occasions, the primary initial presentation was with a cutaneous squamous cell carcinoma in the right axilla. It was not until the third referral, with an ipsilateral breast lump, that breast cancer was clinically diagnosed. This was histologically identified as the primary malignancy, most likely in-keeping with squamous cell carcinoma of the breast. This unique atypical presentation represents a diagnostic challenge and highlights a clinically relevant learning point that may avoid subsequent diagnostic delay. Cutaneous axillary lesions should be treated with a high index of suspicion, necessitating the requirement for chest examination because of the possible presence of an associated primary breast carcinoma.