SUCRASE-ISOMALTASE IS AN INDEPENDENT PROGNOSTIC MARKER FOR COLORECTAL-CARCINOMA

PURPOSE: Expression of disaccharidase sucrase-isomaltase (SI) is signi ficantly enhanced during neoplastic transformation of colonic epitheli um. Our study was designed to determine whether expression of SI withi n primary tumors was significantly associated with survival in patient s with colorectal carcinoma (CRC). METHODS: SI expression was analyzed by immunohistochemistry in paraffin sections from 182 Stage I to III CRC that had been resected for cure at the New England Deaconess Hospi tal between 1965 and 1977. Expression was scored as absent or present in 1 to 50 percent or more than 50 percent of tumor cells. Association s were explored among SI expression, other clinical or pathologic vari ables, and overall survival. The data set is mature, with 91 (56 perce nt) patients who bad died of CRC at a median follow-up of 96 months. R ESULTS: Fifty-five percent of primary CRC expressed SI. When the multi variate Cox analysis was performed, nodal status, T stage, primary sit e, grade, and SI expression were independent covariates. SI expression was not associated with the expression of other clinicopathologic var iables but increased the risk of death from colorectal carcinoma by 1. 83-fold. DISCUSSION: These results indicate that SI is a prognostic ma rker for CRC that is independent of stage-related variables in patient s who have undergone potentially curative resections.