Immunohistochemical analysis of molecules expressed by PEL.

Most tumor cells in clinical samples of PEL display multiple protein expression with membranous and/or cytoplasmic staining. Cytospin preparations, avidin-biotin-peroxidase complex immunostaining, hematoxylin counterstain; original magnification, × 250 (A-D,F); section from cell block, avidin-biotin-peroxidase complex immunostaining, hematoxylin counterstain; original magnification, × 250 (E).