Prognostic significance of perioperative tumor marker levels in stage II/III gastric cancer.

Aim: To evaluate the prognostic significance of perioperative carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9) levels in stage II/III gastric cancer.

Methods: From a multi-institutional retrospective database compiled by integrating clinical data from nine institutions, data of 998 patients who underwent curative resection for stage II/III gastric cancer between 2010 and 2014 were retrieved and analyzed. The prognostic impact of the preoperative and postoperative levels and chronological changes in CEA, CA19-9 and their combination were evaluated. To test whether postoperative adjuvant chemotherapy alters the prognostic impact of perioperative CEA and CA19-9 levels, the hazard ratios for mortality were compared between patients who underwent surgery alone and patients who underwent surgery followed by adjuvant chemotherapy.

Results: The prognostic impact of postoperative CEA and CA19-9 was superior to that of the preoperative levels. Multivariable analysis identified high postoperative CEA and CA19-9 levels as independent prognostic factors for overall survival. Disease-free survival rates clearly decreased in a stepwise manner in association with postoperative CEA and CA19-9 levels, and patients with high levels of both markers showed significantly poorer prognosis than other patient groups. When we analyzed perioperative changes in serum CEA and CA19-9 levels, patients with high levels before and after surgery had the worst disease-free survival rates among all patient groups. Patients with normalized CEA levels after surgery had a significantly lower disease-free survival rate than those with normal perioperative levels, whereas patients with normalized CA19-9 levels after surgery had equivalent survival to those with normal perioperative levels. The prognostic impact of high CEA levels was observably smaller in patients who underwent adjuvant chemotherapy than in patients who underwent surgery alone, whereas that of high CA19-9 was greater in patients who underwent adjuvant chemotherapy. High postoperative CEA levels were significantly associated with an increased prevalence of liver, lung and bone recurrences, and high postoperative CA19-9 levels were significantly associated with increased frequencies of lymph node and liver recurrences.

Conclusion: The evaluation of serum CEA and CA 19-9 levels both before and after surgery provides useful information for precise risk stratification after curative gastrectomy.