Prognostic value of serum tumor antigen CA19-9 after curative resection of colorectal cancer.

BACKGROUND CA19-9 was evaluated as a prognostic marker for colorectal cancer and whether it could be helpful in addition to surveillance using CEA was also tested. MATERIALS AND METHODS Serum CA19-9 levels were measured preoperatively in 1109 patients and monitored at 3-month intervals for the first 2 years postoperatively, and at 6-month intervals thereafter in 700 patients. RESULTS Preoperative high CA19-9 was independent prognostic factor for recurrence. Among patients with recurrence, 21.4% had a high postoperative CA19-9. High postoperative CA 19-9 levels were more likely in patients with high preoperative levels. Postoperative CA19-9 increased more in patients with a peritoneal recurrence than in those with liver metastasis (p=0.002). Among patients with recurrence, CA19-9 increased in 7.8% of the patients with a normal follow-up CEA. CONCLUSION Postoperative CA19-9 was more frequently elevated when peritoneal recurrence occurred. Data on CA19-9 levels provided 7.8% of additional information in predicting recurrence in this study.