Tumor Size As A Prognostic Factor In Patients With Stage Ⅲ Gastric Cancer

AIM:To explore the impact of tumor size on outcomes in patients with stage Ⅲ gastric cancer.METHODS: We retrospectively analyzed the clinical records of 264 patients with stage gastric cancer who underwent D2 curative resection(full stomach or distal or Ⅲproximal stomach cancer radical prostatectomy)in The First Affiliated Hospital of Fujian Medical University from December 2009 to December 2011.Receiver-operating characteristic(ROC)curve analysis was used to determine the appropriate cutoff value for tumor size,which is measured as maximum tumor diameter.Based on this cutoff value,patients were divided into two groups: those with large-sized tumors(LSTs)and those with small-sized tumors(SSTs).The correlations between other clinicopathologic factors and tumor size were investigated,and the 5-year overall survival(OS)rate was compared between the two groups.Potential prognostic factors were evaluated by univariate Kaplan-Meier survival analysis and multivariate Cox’s proportional hazard model analysis.RESULTS: The follow-up rate of all patients was 98.1%,and the median follow-up time is 70.5 months(62.8 84.0).ROC analysis indicated that the sensitivity and specificity results for the appropriate tumor size cutoff value of 45 mm.Using this cutoff value,124 patients were LSTs(tumor size ≥45mm)and 140 were SSTs(tumor size <45mm).By means of two groups of patients with clinical pathologic data were analyzed,and the tumor location and surgical methods such as comparative differences statistically significant(P < 0.05).Two groups of patients with postoperative 5-year survival rate were 20.7% and 37.7% respectively,the differences between the two groups have statistical significance(P < 0.01).The tumor size and lymph node metastasis were the independent factors affecting the prognosis of the whole group,according to the COX proportional risk model analysis(P < 0.05).Independent factors affecting the whole set of outcomes,in turn,hierarchical analysis,found that for the period of N0 patients,its large diameter and small diameter group postoperative 5-year survival rate of no statistical significance(P > 0.05);For patients with N1,the large diameter and small diameter group there was no statistically significant difference of postoperative 5-year survival rate(P > 0.05);For patients with N2,its large diameter and small diameter group after 5 years survival rates were 17.9% and 51.1%,respectively,the differences between the two groups have statistical significance(P < 0.05);For patients with stage N3,its large diameter and small diameter group there was no statistically significant difference of postoperative 5-year survival rate(P > 0.05).CONCLUSION: Using a tumor size cutoff value of 45 mm,tumor size is a prognostic factor in patients with stage Ⅲ gastric cancer.For the N2 Ⅲ period in patients with gastric cancer,the prognosis of patients with tumor size of 4.5 cm or less is better than that of over 4.5 cm.