Figure 3
From: Malignant fibrous histiocytoma of the face: report of a case
(A-D). Histopathological and immunohistochemical findings of the recurrent lesion diagnosed as malignant fibrous histiocytoma of myxoid type: (A) Heterogeneous fibroblastic spindle cells, histiocytic, inflammatory and pleomorphic giant cells are scattered throughout the tumour mass embedded in myxoid stroma containing plentiful collagen fibres. (H&E, 200×). (B) Negative immunohistochemical reaction for cytokeratins [pan-anti-cytokeratin antibody; KL-1 (Ventana, Germany)], (C) Strong positive reaction with the MIB1 antibody showing a high proliferative activity of the tumor, MIB-1 labelling index: 50%(100×), (D) Strongly positive immunohistochemical reaction for vimentin in the vast majority of tumour cells (400×)