We have performed this study to define the usefulness of an anti-human progenitor cell antigen-1(anti-CD34) to distinguish some kinds of soft tissue tumors in formalin-fixed, paraffin-embedded tissues. Sixty three cases of vascular, fibrohistiocytic, neural and other tumors were immunostained for CD34 using the streptavidin-biotin immunoperoxidase method. All of the vascular tumors including he...