the results of the examination of both cases were as follows : the benign tumor ( angiomyoma ) was composed of mainly mature smooth muscle cells having dark cytoplasm , and the malignant tumor ( leiomyosarcoma ) consisted mainly of two types of cells , undifferentiated mesenchymal cells or fibroblast-like cells ( type i ) and myofibroblast-like cells ( type ii ) .
C0016030
fibroblast
C0007634
cells