[Plexiform fibrohistiocytic tumor: a low grade malignancy lesion].

The plexiform fibrohistiocytic tumor is rare. It affects mainly children and adolescent. This tumor occurs at the dermo-subcutaneous region of the upper extremities. We report a case of a 11 year-old child exhibited a nodule on his forearm who is diagnosed as a plexiform fibrohistiocytic tumor. Histologically, it was a plexiform proliferation of spindle fibroblast-like cells associated with mononuclear histiocyte-like cells. Treatement consisted on a large excision and in the follow-up there is no recurrence of the tumor. 'I'he differential diagnosis may be difficult with other tumors in to the derm or sub-cutaneus adipose tissu, having a plexiform pattern or a predominantly fibroblastic pattern like the fibromatosis and well differenciated fibrosarcoma. This tumor reccured in 20 to 30 % of the cases. Lymph node and pulmonary metastasis are rare. This clinical behaviour leads authors to class it into a "borderline tumor".