Differentiation state specific localization of the carcino-embryonic antigen (CEA) on ultrathin cryosections of breast, stomach and lung lesions.

The ultraimmunohistochemical localization of carcinoembryonic antigen (CEA) in breast, gastric and lung tumours at various stages of differentiation showed that CEA is mainly located on well differentiated tumour cells, the subcellular morphometric data of which resembled more those of benign lesions rather than those of malignant tumours. All these cells were characterized by raised surface to volume ratios as compared to normal cells. The CEA labels were mainly found on the cell membranes, the outer nuclear membrane and the rough endoplasmatic reticulum (rER). Mono- and poly-clonal antibodies produced a similar labelling pattern, but the former appeared to have less affinity for glycocalix-associated structures than the latter.