Simultaneous detection of intercellular adhesion molecule-1 (CD54) and carcinoembryonic antigen in lung adenocarcinoma.

Simultaneous detection of intercellular adhesion molecules-1 (ICAM-1) and carcinoembryonic antigen (CEA) was investigated in AMeX (Acetone, Methyl benzoate and Xylene)-fixed, paraffin-embedded tumor sections of 24 adenocarcinomas of the lung, using the avidin-biotin-peroxidase complex (ABC) method. Distinct expression of both ICAM-1 and CEA was found in tumor cells in all cases. The staining pattern of these two antigens was quite similar and was mainly affected by the tumor grade. In well-differentiated adenocarcinoma, uniformly positive staining was demonstrated predominantly along the apical surfaces of the tumor cell nests, and to a lesser degree on the lateral cell surface and in the cytoplasm with apical concentration, but no positive staining was found on the basal cell surfaces. In poorly differentiated adenocarcinoma, positive staining was found along the entire cell surface and in the cell cytoplasm without any apical concentration, and the staining intensity varied from region to region in the same tumor cell and from cell to cell within the same tumor cell nest. In moderately differentiated adenocarcinoma, the staining pattern was intermediate between those of well and poorly differentiated adenocarcinoma with some degree of apical concentration. The expression pattern of ICAM-1 or CEA on tumor cells did not correlate well with stromal inflammatory cell infiltration. These results indicate that the expression pattern of CEA and ICAM-1 is an inherent characteristic of tumor cells, and that their abnormal expression may play an important role in the physiological behavior of tumor cells because the polarity of their expression is lost in parallel with histological tumor grades.