Immunohistochemical demonstration of breast-derived and/or carcinoma-associated glycoproteins in normal skin appendages and their tumors.

Sixty-six benign and malignant skin appendage tumors were studied for the expression and localization of the glycoproteins identified by the monoclonal antibodies (MoAbs) GCDFP-15, CU18, B72.3, and VU-1D9. Formalin-fixed, paraffin-embedded tissue was processed by the avidin-biotin complex method. In normal eccrine and apocrine sweat glands, GCDFP-15, CU18, B72.3, and VU-1D9 staining was localized differently (intracellular, membranous, or intraluminal), whereas eccrine glands showed no B72.3 staining. There were various patterns of positive staining of tumors arising from sweat glands, but no immunoreactivity for B72.3 was found in eccrine-derived tumors. CU18 and VU-1D9 labeled mature sebocytes in a vacuolar fashion and stained sebaceous carcinomas. VU-1D9 labeled membranes of the secondary germ cells in early anagen of a hair follicle bulb as well as the basaloid cells of trichoepitheliomas and basal cell carcinomas. These MoAbs appear to be valuable markers for the study of normal skin appendages and their tumors.