The clinical significance of sialoglycoprotein antigens in colorectal cancer

This study aimed to investigate the clinical significance of sialyl LewisX (SLX) and sialyl LewisA (SLA) expression on colorectal cancer. Immunohistochemical staining was performed using resected specimens from 188 colorectal cancer patients. Specimens in which antigens expressed less than 5% of total cancer glands were regarded as antigen-negative, whereas more than 5% were scored as antigen-positive. The positive SLX expressions on primary tumors were seen in 80.6% of patients with hepatic metastases, as opposed to 42.1% in patients without metastases (p <0.01). Multiple logistic regression analysis indicated that SLX significantly correlated with hepatic metastasis as with lymph node involvement, invasion depth and vessel invasiveness. In addition, SLX expression significantly correlated with asynchronous hepatic metastasis. Five-year survival rates were significantly worse among SLX positive patients than among negative patients (53.3% vs. 81.2%, p <0.01). These results suggested that SLX is a very sensitive marker which is associated with hepatic metastasis and poor prognosis.