H, peanut lectin receptor, and carcinoembryonic antigen distribution in keratoacanthomas, squamous dysplasias, and carcinomas of skin.
The distribution of blood group antigen H(O), peanut lectin receptor (PNL-R) (a precursor to the MN blood group antigens), and carcinoembryonic antigen (CEA) was examined in 15 squamous cell carcinomas, 10 keratoacanthomas, 17 squamous dysplasias, and 5 normal controls using immunoperoxidase techniques. All controls and 8 carcinomas, 10 keratoacanthomas, 14 dysplasias expressed H antigen. All controls and 9 carcinomas, 10 keratoacanthomas, 16 dysplasias expressed PNL-R antigen. CEA was present in 15 carcinomas, in trace amounts in 3 keratoacanthomas, in 6 dysplasias, and in 0 controls. The staining for H antigen and PNL-R in the carcinomas and dysplasias was disorganized, patchy, and less than that of normal epithelium, while staining in keratoacanthomas was uniform, with normal to increased intensity as compared to controls in 9 cases. CEA showed weak focal staining in 5 carcinomas, 8 dysplasias and 3 keratoacanthomas, and more intense and extensive cytoplasmic and membrane staining in 10 carcinomas and 5 dysplasias, and no cellular staining in 4 dysplasias and 7 keratoacanthomas. CEA was present in greatest amounts in the well-differentiated carcinomas and focal in the less-differentiated tumors. The well-differentiated carcinomas had a greater percentage of cells staining for H antigen and PNL-R. The pattern of staining for H, PNL-R, and CEA appears to distinguish keratoacanthomas from carcinomas and squamous dysplasias, and may be a useful adjunct to diagnosis.