Carbohydrate antigens and liver metastasis in colorectal cancer

A comparative immunohistochemical study was performed to analyse the expression of cancerassociated carbohydrate antigens by primary and metastatic lesions of colon cancer. We used monoclonal antibodies which reacted with Le^a, Le^x and Tn as well as their sialylated derivatives. Twenty-one primary lesions in patients without metastasis and 26 primary and metastatic lesions in patients with liver metastasis were studied. Sialyl Le^a was expressed by 57% of the primary lesions of patients without metastasis, 65% of the primary lesions of patients with metastasis and 73% of their liver metastases. Sialyl Le^x was expressed by 60% of the primary lesions of patients with and without metastasis as well as by approximately 80% of the liver metastases. Sialyl Le^a and sialyl Le^x showed strong expressions in the liver metastases, significantly greater than in the primary lesions. The findings indicate the increased expressions of sialyl Lea and sialyl Lex to be correlated with liver metastasis of colorectal cancer.