ultrastructurally , fibrosarcomas produced by 155-4t1 and u-15t1 consisted mainly of fibroblast-like cells with extracellular collagen fibers , whereas malignant fibrous histiocytoma-like lesions produced by u-26t1 consisted of undifferentiated cells , multinuclear giant cells , histiocyte-like cells , and fibroblast-like cells .
C0334463
malignant fibrous
C0017526
giant cells