Bilateral pseudoangiomatous stromal hyperplasia in a human immunodeficiency viral-infected patient

Pseudoangiomatous stromal hyperplasia (PASH) is an uncommon mesenchymal neoplasm of the breast demonstrating stromal myofibroblastic proliferation and having the appearance of anastomosing slit-like pseudovascular spaces lined by spindle-shaped cells. A case of nodular PASH of the bilateral breasts in a 40-year-old woman with clinically presenting with a progressive enlarged breast lump is reported. Mammographic and ultrasonographic features of the right and left breasts showed a large solid lump with well-circumscribed border measuring 4 cm × 1.7 cm × 3.4 cm and 13.8 cm × 10.9 cm × 12.1 cm, respectively. Wide excision of the right breast and quadrantectomy of the left breast were performed. The histopathological examination of the lesion showed anastomosing slit-like pseudovascular spaces. The stromal cells were immunoreactive for muscle actin (HHF35), smooth muscle actin, and progesterone receptor. Clinical and pathological findings with briefly reviewed relevant literatures are discussed. This is the first clinicopathological and radiological report of bilateral mammary nodular PASH in a human immunodeficiency viral-infected patient.