angiofibroma of soft tissue

PO

Differential diagnosis

 cellular angiofibroma

• usually in genital region, more cellular, usually ER+, PR+

 low-grade fibromyxoid sarcoma

• often > 6 cm and infiltrative, 45% have epithelioid areas, 40% contain poorly formed but large collagen rosettes

 low-grade myxofibrosarcoma

• infiltrative borders, often sends out long tentacles, more solid areas are often seen similar to typical undifferentiated pleomorphic sarcom; has curvilinear vessels (thick walled with broad arc) with condensation of cells around vessels

 myxoid liposarcoma

• prominent chicken wire vasculature, numerous signet ring lipoblasts particularly at periphery of lobules, mucoid matrix rich in hyaluronidase sensitive acid mucopolysaccharides, may have large mucoid pools, S100+

 solitary fibrous tumor

• fibroblast like cells with patternless pattern, thick bands of collagen and prominent branching, hyalinized vessels; CD34+, CD99+