0000000000132885
AUTHOR
M.a. Martorell
Fibroblast and Myofibroblast Participation in Malignant Fibrous Histiocytoma (MFH) of Bone
Eight malignant fibrous histiocytomas (MFH) of bone were studied with immunohistochemistry and electron microscopy. Ultrastructurally, fibroblasts and myofibroblasts were the main tumor cells in four cases and abundant in two other cases; these cells showed immunohistochemical positivity to alpha 1-antitrypsin, vimentin and anti-muscle antigen (HHF 35). Moreover, histiocytic-like tumor cells were electron-microscopically detected in four cases, being the main tumor cell type in two of the cases; immunohistochemically these cells expressed positivity to alpha-1-antichymotrypsin (A1ACT), alpha-1-antitrypsin (A1AT) and vimentin. Present results confirm the cellular heterogeneity of MFH of bone…
Primary omental tumor with ultrastructural features of cellular schwannoma and absence of S-100 antigen reactivity.
Summary We report a primary well-delimited, large mesenchymal omental neoplasm which appeared in a 58 year old man without neurofibromatous traces. The histological and ultrastructural features were consistent with a Schwann cell origin. However, repeated immunohistochemical reactions failed to demonstrate protein S-100 antigen reactivity in the neoplasic cells, the latter only expressing vimentin. The differential diagnosis with hemangiopericytoma is proposed.