Pseudoangiomatous stromal hyperplasia (PASH) presenting as axillary lump: case report and review of the literature.

Pseudoangiomatous stromal hyperplasia (PASH) is an uncommon benign mesenchymal breast lesion. There are extremely rare reports of PASH arising in accessory breast tissue. To date, in literature, fewer than 10 cases of PASH occurring in axillary region have been described. We report a case presenting as axillary lump in a young woman. A 20-year-old female presented to our surgical unit for a progressively growing and painful palpable mass of the right axilla for about a year. Before surgery an ultrasound was performed. The patient underwent local excision of the lesion under local anaesthesia. Through histological and immunohistochemical examination a pseudoangiomatous stromal hyperplasia (PASH) was diagnosed. At 6 months of followup the patient is free of disease. It is important to include PASH also in the differential diagnosis of axillary lumps. Histological examination of the surgical specimen and surgery represent, respectively, the mainstay for diagnosis and therapy.