Long-term outcome after endoscopic submucosal dissection for early gastric cancer: focusing on a group beyond the expanded indication.

Objective: To determine the long-term outcome after endoscopic submucosal dissection (ESD) in patients with early gastric cancer (EGC) according to the pathological extent.

Methods: ESD were performed in 280 patients with 309 EGC. The tumors were classified by pathological severity based on absolute indication (AI), expanded indication (EI) or beyond expanded indication (BEI). The therapeutic outcomes among the three groups were analyzed.

Results: The complete resection rates of EGC were 96.4%, 78.7% and 41.2% in the AI-EGC, EI-EGC and BEI-EGC groups, respectively (P = 0.000). En bloc resection rates were 97.6%, 87.4% and 86.3% in the AI-EGC, EI-EGC and BEI-EGC groups, respectively (P = 0.023). The 5-year tumor recurrence rates were 1.8%, 1.5% and 15.4% in the AI-EGC, EI-EGC and BEI-EGC groups, respectively (P = 0.000). The 5-year disease-specific survival rates were 100%, 100% and 97.4% in the AI-EGC, EI-GEC and BEI-EGC groups, respectively (P = 0.088). The 5-year disease-free survival rates were 98.2%, 98.5% and 84.6% in the AI-EGC, EI-EGC and BEI-EGC groups, respectively (P = 0.000).

Conclusions: ESD was effective and safe in treating AI-EGC and EI-EGC, but there was a comparatively high rate of recurrence after ESD in the BEI-EGC group. However, long-term outcomes of patients with BEI-EGC that did not receive additional surgery were better than those with an natural course of EGC. Thus, ESD may be considered for specific BEI-EGC patients at high risk for surgery.