Epithelioid malignant schwannoma : a study of 14 cases

摘要: We report a light and electron microscopic, immunohistochemical, clinical prognostic study of 14 patients with epithelioid malignant schwannoma. In 8 the tumour involved major nerve. The tumours were rather small in most instances, largest diameter being less than 5 cm 7 cases. Light microscopically, they showed highly cellular areas epithelioid, polygonal or rounded cells characteristically forming cords rows arranged nodules varying size. Spindle cell sarcoma as classical schwannoma seen 9 cases, neurofibromatous one case. Four cases entirely appearance. Electron microscopically nuclei mostly even contours containing two trabecular reticular nucleoli, cytoplasmic projections, intra-cytoplasmic myelin-like figures, intercellular junctions discontinuous, sometimes multilayered external lamina material. ultrastructural findings indicate that is neural crest derivation having features Schwann differentiation. Immunohistochemically, S-100 protein was demonstrated neuron specific enolase 3. There female predominance, 9/14, median age 38.5 years (range 17-74). extremities, including hip shoulder regions, common sites, 12/14. proved malignant; dead at time follow-up high incidence metastasis (7 14) observed.