Increased expression of sialyl Lex antigen in non-polypoid growth type of colorectal carcinoma

Colorectal carcinoma can be morphologically divided into two different categories, namely polypoid growth (PG-type) and non-polypoid growth (NPG-type). To ascertain whether the expression of sialyl Lex antigen correlates with biologically and clinically important differences, an immunohistochemical assay was performed in 30 PG-type and 119 NPG-type cancers. In contrast to PG-type, the characteristics of the NPG-type include (1) an increased expression of sialyl Lex; (2) a high rate of lymph node metastasis; (3) a high proportion of moderately differentiated adenocarcinoma cells; (4) young age of onset. It is concluded that differences in sialyl Lex expression between the PG-type and NPG-type cancers may be at least partly responsible for different tumor progression behavior.