OLIGOSACCHARIDE LE(A)-LE(X) - A CELL-SURFACE MARKER FOR CARCINOMAS DERIVED FROM EMBRYONIC ENDODERM

An immunohistochemical evaluation of Le(a)-Le(x) expression by adenoca rcinomas of the biliary tree, pancreas, colon and stomach was undertak en as examples of epithelial tumors derived from embryonic endoderm. T his complements previous studies showing that Le(a)-Le(x) was present on the cell surface of non-small cell lung carcinomas, some non-lung c arcinomas, and is a prognostic marker for squamous cell lung carcinoma s. All of the tumor specimen evaluated were positive and no expression of Le(a)-Le(x) was detected in derivatives of neural, connective or m uscle tissues. These findings indicate that it could be informative to examine the biological significance of Le(a)-Le(x) not only in carcin ogenesis but during embryogenesis, as well.