Hemangioblastoma of pelvic cavity: report of a case and review of literature.

Hemangioblastoma of soft tissue is a very rare tumor of uncertain histological type. Herein, we reported a 51-year-old woman was found to have a solid and cystic mass measuring 31×30 mm in the right adnexa area on a computed tomography scan. The tumor showed the typical histology of hemangioblastoma. Tumor was composed of numerous capillaries and stromal cells with cytoplasmic vacuolization. Immunohistochemical study revealed that the tumor stromal cells were positive for CD56, S-100 protein, NSE, Syn, CgA, and inhibin-α. Focal EMA positivity was present. Ki-67 expression was found in approximately 1% of tumor cells. The tumor cells were negative for CK, HMB-45, Melan-A, SMA, and CD68. The differential diagnosis of Hemangioblastoma arising in pelvic cavity includes hemangioma, hemangioendothelioma, liposarcoma, renal cell carcinoma, fat-forming solitary fibrous tumor, paraganglioma, and perivascular epithelioid cell tumor (PEComa).