The usefulness of serum tumor markers for assessing gastric carcinoma is very limited compared to that for neoplasms in other digestive organs. Many reports have shown that serum tumor markers are closely associated with the prognosis and tumor recurrence in gastric cancer patients. However, little is known about the usefulness of serum tumor markers as a predictor of distant metastasis for gastric carcinoma.

With excluding the non-specific causes of elevated tumor markers, a total of 788 patients with gastric carcinoma and who were seen at our hospitals between 2004 and 2006 were included in this study. The correlation between the preoperative level of tumor makers and the clinicopathological features was analyzed.

CEA was significantly correlated with age, gender and nodal metastasis, but not with the depth of tumor. The CEA level was not correlated with distant metastasis, such as peritoneal or hematogenous metastasis. In contrast, the CA 19-9 level was significantly correlated not only with the depth of tumor and nodal metastasis, but also with peritoneal metastasis. Especially, the patients with over 500% elevation of the CA 19-9 level had a significant risk of peritoneal metastasis.

CA 19-9 is useful for predicting peritoneal metastasis in gastric cancer patients. It can be used efficiently in making the diagnostic and the treatment plan, in combination with other diagnostic tools, for gastric cancer patients.