Pleomorphic Hyalinizing AngiectaticTumor

Overview

Authors present an additional case report of pleomorphic hyalinizing angiectatic tumor (PHAT),only recently recognized entity amongst the soft tissue tumors. 63-year-old man underwent surgery for subcutaneous tumor growing on the forearm. Grossly, ovoid well demarcated tumor 4,0 x3,5 x 2,5 cm was removed. Histologically, hypovascular areas of spindle-cells arranged in sheetsand fascicles resembling spindle-cell sarcoma and areas rich on ectatic vessels with fibrin deposits or thickened hyalinized walls were present. Some cells contained intranuclear cytoplasmaticinclusions, lobulated nuclei with or without prominent nucleoli or multiple nuclei. Mitoses wereless than 1 per 30 HPF, Ki-67 nuclear positivity was observed in 2,6% of tumor cells. Immunohistochemically, cells were positive with vimentin, but negative for CD34, S100, desmin, smooth-muscleactin, EMA, VWF, CD99, bcl-2 and cytokeratins. The patient did well, without recurrent tumorafter 13 months follow-up. Spectrum of tumors including solitary fibrous tumor, giant-cell angiofibroma, neurilemmoma, malignant fibrous histiocytoma and acral myxoinflammatory tumor withatypical bizarre giant cells is discussed in differential diagnosis.

Key words:
pleomorphic angiectatic hyalinizing tumor - sarcoma - soft parts - vasculature - solitary fibrous tumor