Preoperative serum levels of sialyl Lewis(a), sialyl Lewis(x), and sialyl Tn antigens as prognostic markers after curative resection for colorectal cancer.

In this study, we examined the preoperative serum levels of sialyl Lewisa, sialyl LewisX, sialyl Tn, and carcinoembryonic antigen in 243 colorectal cancer patients in order to clarify the role of these antigens as prognostic factors after curative surgery. The patients were divided into two groups: low and high antigen groups (lower and higher than a selected diagnostic-based cut-off value). Patients with high serum levels of sialyl Lewisa and carcinoembryonic antigen had shorter disease-free intervals than those with low serum levels of the respective antigen, although sialyl Lewisx and sialyl Tn showed no significant differences. Multivariate analysis revealed that three independent prognostic variables, including depth of tumor invasion, lymph node metastasis, and serum sialyl Lewisa level, did prove to have value in predicting disease-free interval. In conclusion, among the four antigens examined in this study, the preoperative serum level of sialyl Lewisa is the only independent prognostic variable for recurrence after curative resection of colorectal cancer.

Comparison of the expression of ABH/Lewis-related antigens in polypoid and non-polypoid growth types of colorectal carcinoma.

BACKGROUND AND AIMS: Colorectal tumors can be classified based on their growth pattern into the polypoid growth-type (PG-type) and non-polypoid growth-type (NPG-type). To ascertain whether there is any relationship between the expression of particular blood group-related antigens (A, B, H, Lewis (Le)a, sialyl Le(a), Le(x), sialyl Le(x)) in a colorectal tumor, and a tumor having polypoid or non-polypoid growth, we examined 78 PG-type and NPG-type colorectal cancers. METHODS: Fourteen PG-type and 64 NPG-type colorectal carcinomas were subjected to immunohistochemical analyses by using monoclonal antibodies against A, B, H, Le(a), sialyl Le(a), Le(x) and sialyl Le(x). RESULTS: The patients with NPG-type carcinomas had a significantly younger age of onset, significantly smaller maximal tumor diameter, significantly higher rate of lymph node metastasis and significantly worse prognosis than those with PG-type carcinomas. Among the 32 tumors of patients with blood type A or AB, isoantigen A was expressed in a significantly larger percentage of NPG-type carcinomas than PG-type carcinomas (95.8 vs 62.5%, respectively; P=0.014). Among all 78 tumors, sialyl Le(x) antigen was expressed in a significantly larger percentage of NPG-type than PG-type carcinomas (90.6 vs 64.3%, respectively; P=0.010). Multivariate analysis using the logistic regression model revealed that isoantigen A and sialyl Le(x) expression were independent predictive risk factors for the development of NPG-type colorectal carcinoma. CONCLUSIONS: These data suggest that the expression of isoantigen A and sialyl Le(x) in a colorectal carcinoma partially determines whether the tumor will have polypoid or non-polypoid growth.