A middle-aged female presented with a 7-month history of a non-tender mobile lump in the right axilla. Ultrasonography demonstrated a 40×38 mm lymph node with no hilum. A smaller (28×25 mm) mammographically detected axillary lymph node had been resected from the patient's right axilla 3 years earlier, at which time histology reported a benign squamous epithelial cyst inclusion. The clinical and radiological breast examination was normal on both occasions.

Following a non-malignant, yet inconclusive, ultrasound-guided needle core biopsy result, the lymph node was surgically excised from the lower axilla (level 1) where it was attached on the serratus anterior muscle. Complete histological examination reported reactive changes and multiple cysts lined by keratinising squamous epithelium (figure 1), with no evidence of cellular atypia or …