[Expression and prognostic indicators of type 1 and type 2 Lewis blood group antigens in colorectal cancers].

The immunohistochemical analysis using the monoclonal antibodies to the blood group antigens was performed on the tissues of 387 colorectal cancers and 307 normal colonic tissues, and the relation between expression of these antigens and prognosis of the patients with stage 2 was also investigated. La, Le(b), and CA 19-9 were used for type 1 antigens, and Le(x), Le(y), and Sialyl Le(x) for type 2, respectively. Expression of Ca 19-9 and Silyl Le(x) remarkably increased in cancers throughout the colorectum. Le(b) and Le(y) were expressed in only 0-17% of the normal distal colon, but in almost colonic tumors. Therefore CA 19-9 and Sialyl Le(x) are tumor-associated antigens in the whole colorectum, and Leb and Le(y) in the distal colon. Expression of CA 19-9 in primary tumor provided more prognostic information and risk of liver metastasis than other Lewis blood group antigens.