Comparison between endoscopic submucosal resection and surgery for the curative resection of undifferentiated-type early gastric cancer within expanded indications: a nationwide multi-center study.

BACKGROUND AND AIMS: Endoscopic submucosal dissection (ESD) for undifferentiated early gastric cancer (UD EGC) has debate due to the risk of lymph node metastasis. We investigated the outcomes of ESD compared to those of surgery for the UD EGC within expanded indication. METHODS: We reviewed 971 UD EGC patients performed ESD across 18 hospitals in Korea and 1812 patients who underwent surgical resection in two hospitals between February 2005 and May 2015. Of these cases, we enrolled a curative resected ESD group of 328 patients and surgery group of 383 cases within an expanded indication. Overall outcomes and one-to-one propensity score-matched (218 ESD group vs 218 surgery group cases) outcomes for these two groups were analyzed. RESULTS: Over the 75.6 month median follow-up period for the 711 enrolled cases, recurrences occurred in 22 patients (6.7%) in the ESD group but not in the surgery group. Overall survival (OS) was higher in the surgery group (p = 0.0316) in all cases, but there was no significant difference after propensity score matching (p = 0.069). According to the histologic type in propensity score matching, the OS of signet ring cell carcinoma and poorly differentiated carcinoma patients did not differ between the ESD and surgery groups (p = 0.1189 and p = 0.3087, respectively). In the surgery group involving expanded criteria, lymph node metastasis was found in six cases (1.56%). CONCLUSIONS: Although ESD shows comparable outcomes to surgery for the UD EGC within expanded indications, appropriate patient selection is needed for the ESD due to the possibility of lymph node metastasis.

External Validation of an Eastern Asian Nomogram for Survival Prediction After Gastric Cancer Surgery in a European Patient Cohort.

Several nomograms for survival prediction after curative gastric cancer surgery have been published over the recent years. Previous validation studies failed to prove applicability of Eastern Asian nomograms in Western patients. Here we present data on a validation analysis of a newly developed Korean nomogram in a German patient cohort.Among a total of 2771 patients having been treated in the Department of Surgery of the Technische Universitaet Muenchen from 1982 to 2008, 908 patients were eligible to undergo this analysis. Patients were treated according to Japanese Gastric Cancer guidelines and followed up on a regular basis for at least 60 months postoperatively. Baseline characteristics were compared using χ-testing. Survival analyses were computed with the Kaplan-Meier method and multivariate regression analysis models. The C-statistics and Hosmer-Lemeshow chi-square statistics were computed for comparisons of the nomogram's predictive ability.All baseline characteristics were significantly different (P < 0.0001) between Korean and German patients except Union Internationale Contre le Cancer-stages (P = 0.427). Multivariate regression analysis revealed the same predictive factors for overall survival in the German and Korean cohorts, respectively, with the exception of tumor size >10 cm and an exclusive correlation of whole stomach spread and pN1-stage for German patients only. The C-index was 0.76, representing an adequate value for predictability of the Korea nomogram in German patients. The Hosmer-Lemeshow statistic implied applicability of the nomogram in the TUM-cohort.A newly developed multicenter Korean nomogram for survival prediction after curative gastric cancer surgery may be applicable for estimating survival prognosis in Western (European) patients.