Inflammatory fibrosarcoma: another imitator of Hodgkin's disease?

We report a case of inflammatory fibrosarcoma occurring in a 49 year-old man, that manifested with distinct multinodular masses in the mesentery. Histologically, the lesion was characterized by spindle fibroblast-like cells, histiocytes, pool of lymphocytes and eosinophils, abundant fibrous to hyaline stroma, and numerous "ganglion" cells. Of special interest was the presence of large multinucleated tumor cells which displayed optically clear nuclei and prominent nucleoli, bearing a deceitful resemblance to the diagnostic Reed Sternberg cells of Hodgkin's disease. The differential diagnosis between the two conditions rests on the evaluation of the appropriate clinical background, as well as on an in-depth assessment of the basic pathologic features. Immunohistochemical reactivity of spindle and ganglion cells for actin along to complementary negativity for CD15, and CD30 further assists in separating the two conditions.