MALIGNANT FIBROUS HISTIOCYTOMA OF THE CECUM - REPORT OF A CASE AND REVIEW OF THE LITERATURE

Malignant fibrous histiocytoma (MFH) of the gastrointestinal tract is extremely rare. Here we report a case of MFH of the cecum and review o ther cases of large bower MFH in the literature. A 64-year-old man had a large tu mor mass in the cecum associated with multiple small perit oneal implants. Histologically, most of the lesion showed inflammatory pseudotumor-like appearance; that is, a mixed proliferation of fibrob lasts and myofibroblasts loosely arranged in sweeping fascicles or who rled structures and an admixture of chronic inflammatory cell infiltra te. The myofibroblastic nature of the spindle-shaped cells was confirm ed by their immunohistochemical and ultrastructural findings, In addit ion, there was atypical histiocytic-cells infiltrate in some areas and marked lymphatic involvement and lymph node metastasis by such histio cytic cells. These features were interpreted as MFH, although it had t o be distinguished from inflammatory fibrosarcoma and leiomyosarcoma. The differential diagnosis is discussed here.