Pseudoangiomatous Stromal Hyperplasia of the Breast A clinicopathological study of 8 cases

ABSTRACT

Pseudoangiomatous stromal hyperplasia (PASH) of the breast occurs in premenopausal women and is characterized by anastomosing channels lined by spindle cells. It has been suggested to be of hormonal origin. This unusual condition may also be mistaken for a vascular tumor. We analyzed eight cases of PASH of the breast in Samsung Cheil Hospital from 1992 through 1998. All patients were premenopausal and had painless breast lump. Clinical diagnoses were fibroadenomas. Grossly, the masses were well circumscribed, nonhemorrhagic and measure 2.2 to 5 cm. Histologically, they consisted of complex interanastomosing channels lined by slender spindle cells, which resembled low grade angiosarcoma. Cells that line the interanastomosing channels showed no immunoreactivity for Factor VIII and electron microscopic findings consistent with fibroblast. All patients were treated with surgical excision and none of them had recurrence for 1 to 69 months (mean 19 months) postoperatively. Pathologic diagnosis of PASH may be difficult unless the pathologists are aware of the presence of a mass lesion and appreciate the characteristic stromal changes. PASH should be included in the differential diagnosis of a circumscribed mass, especially in the premenopausal women.