PLEXIFORM FIBROHISTIOCYTIC TUMOR WITH NOVEL PHENOTYPIC FEATURES

Plexiform fibrohistiocytic tumour is a recently described type of fibr ohistiocytic tumour, the differentiation pattern of which is poorly un derstood. A case representing the predominantly fibrohistiocytic type of the tumour is reported. Immunohistochemical analysis supports the h istiocytic origin of this entity. The expression of EBM/11 and tissue transglutaminase both in fibroblast-like and histiocyte-like cells ind icate that a single cell line produces the dual morphological features . It is proposed that a non-phagocytic epithelioid pattern of histiocy tic differentiation characterizes this tumour.