Peritoneal recurrence in gastric cancer following curative resection can be predicted by postoperative but not preoperative biomarkers: a single-institution study of 320 cases

To determine the risk factors for peritoneal recurrence in gastric cancer patients after curative resection, we included 320 patients with stage I-III primary gastric cancer between January 2008 and June 2012. Data on each patient's surgical and pathological information, preoperative and postoperative tumor markers were collected and analyzed retrospectively. The risk factors for peritoneal recurrence were investigated by univariate and multivariate analysis. In patients with peritoneal recurrence, advanced T or N stage, low differentiation, vascular/lymphatic invasion, perineural invasion, and elevated postoperative CEA/CA19-9 were more common than in patients without peritoneal recurrence. Patients with peritoneal recurrence showed a worse overall survival (OS) compared to those without peritoneal recurrence. In addition, patients with peritoneal recurrence within the first year had a worse OS compared to those with recurrence after 1 year. The univariate and multivariate analyses revealed that elevated number of metastatic lymph nodes and elevated postoperative CEA and CA19-9 were three independent risk factors for peritoneal recurrence in gastric cancer patients. For patients with N3 stage and high postoperative CEA and CA19-9, we found an initial steep slope within approximately 1 year and a subsequent gentle slope in the risk curve. Combined receiver operating characteristic curve analysis using the three independent risk factors for peritoneal recurrence yielded an area under the curve value of 0.73 with 73.7% sensitivity and 64.2% specificity. Therefore, the risk factors may be associated with peritoneal recurrence after curative resection in selected gastric cancer patients.