Angiomyofibroblastoma of the vagina in a postmenopausal breast cancer patient treated with tamoxifen: clinicopathologic analysis of a case and review of the literature.

Angiomyofibroblastoma is a rare mesenchymal tumor. This study presents the clinical, histologic, and immunohistochemical features of an angiomyofibroblastoma of the vagina occurring in an 80-year-old breast cancer patient under prolonged treatment with tamoxifen. Histologically, the tumor was characterized by alternating hypercellular and hypocellular edematous zones and small- to medium-sized blood vessels, which were characteristically thin walled. The tumor cells were spindle shaped (mainly) or round shaped (occasionally) arranged in cords and nests. The stroma was edematous and contained inflammatory cells, especially lymphocytes and mast cells. Immunohistochemistry of the tumor cells revealed diffuse and intense immunoreactivity for vimentin and desmin. The staining for estrogen receptors and progesterone receptors was positive, with a percentage of 70% and 40%, respectively. In conclusion, the tumor was diagnosed as an angiomyofibroblastoma based on its typical histologic and immunohistochemical features. The expression of estrogen and progesterone receptors suggests that it might arise as a neoplastic proliferation of hormonally responsible mesenchymal cells. Tamoxifen may exert stimuli effects upon mesenchymal cells.