Clinical importance of preoperative carcinoembryonic antigen and carbohydrate antigen 19-9 levels in gastric cancer

Although serum carcinoembryonic antigen (CEA) and carbohydrate antigen (CA) 19-9 are commonly measured before surgery for gastric carcinoma, this clin ical significance is not fully understood. We evaluated a total of 549 pati ents with gastric cancer who underwent gastrectomy. Levels of CEA and CA19- 9 were measured preoperatively in all patients. We retrospectively analyzed correlations between CEA or CA19-9 and clinicopathologic features, and est imated the prognostic utility of the tumor markers by analyzing clinicopath ologic characteristics of the carcinoma as a function of seropositivity or negativity of the antigens in combination or by raising the levels. The pos itivity rates of CEA (greater than or equal to5 ng/mL) and CA19-9 (greater than or equal to 37 U/mL) were 19.5% and 18%, respectively. Serum CEA and C A19-9 positivity significantly correlated with depth of invasion, hepatic m etastasis, and curativity. Forty nine patients positive for both CEA and CA 19-9 had significantly higher frequencies of lymph node metastasis, deeper invasion by the tumor, lower rates of curative resection (p < 0.01), and hi gher rates of hepatic metastasis (p < 0.05) than 377 patients with normal l evels of CEA and CA19-9. Surgical outcomes of patients who were CEA- and CA 19-9-positive were poorer than those of patients with normal CEA and CA19-9 levels (p < 0.01). Significant correlation was found between serum CEA and CA19-9 level (p < 0.001, r = 0.24). Doubling the threshold level of serum positivity to 10 ng/mL (CEA) and 74 U/mL (CA19-9) improved the prognostic v alue of these factors. However, multivariate analysis using Cox's hazards m odel revealed that only CEA positivity using the doubled threshold value (1 0 ng/mL) (p = 0.04, hazard ratio = 1.7), nodal involvement (p = 0.01, hazar d ratio = 1.9), and depth of invasion (p = 0.02 hazard ratio = 1.5) signifi cantly predicted prognosis. Carcinoembryonic antigen positivity using the d oubled threshold level (10 ng/mL) was an important prognostic factor in pat ients with gastric cancer.