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

Abstract

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-toone 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.

Comparison of long-term outcomes of endoscopic submucosal dissection and surgery for undifferentiated-type early gastric cancer meeting the expanded criteria: a systematic review and meta-analysis

“…In our study, we found that ESD was associated with inferior OS to surgery in the overall cohort but not in the PSM cohort. These results are consistent with the results of the most recent and largest cohort study [ 14 ]. Prior studies suggested no significant difference in the OS between ESD and surgery both before and after PSM, which indicates the possible low study power of these studies [ 13 , 28 – 30 ].…”

“…Because two studies included patients who underwent noncurative ESD for UD EGC, we contacted the authors and provided data for patients with curative ESD only [ 13 , 30 ]. In addition, there were some data duplications between the two studies [ 14 , 29 ]. Therefore, we contacted the authors and provided data after excluding duplicated records.…”

“…In the sensitivity analysis, HR was directly derived from two studies [ 14 , 29 ] while being indirectly estimated in the others [ 13 , 28 , 30 ]. The results were consistent with those in the main analysis (Supplemental Table 3 and Figs.…”

“…The characteristics of the excluded studies are listed in Supplemental Table 2. Based on these, five articles that fulfilled the eligibility criteria were included [13,14,[28][29][30]. None of the studies were RCTs; they were all retrospective cohort studies.…”

“…Several case reports also described UD EGCs that satisfied the expanded criteria but had LN metastasis [10][11][12]. Moreover, previous retrospective studies have reported cases of extragastric recurrence years after curative ESD for UD EGC [13,14]. In addition, poorly differentiated adenocarcinoma (PDA) was reported to harbor a higher risk of LN metastasis than signet ring cell carcinoma (SRC) [15].…”