The pathological examination results of HE-stained tissue sections indicated that tumor cells were short fusiform or elliptical and significantly atypical, with visible pathological mitosis, mononuclear or multinuclear tumor giant cells, thus morphologically complying with malignant tumor; immunohistochemistry (tumor cells) showed Vimentin (+), desmin (less) (+), Ki67 50% (+), CK (–), GFAP (–), S-100 (–), CD34 (–), Actin (–). The gene discussed is VIM; the disease is neoplasm.