OBJECTIVES: Endoscopic submucosal dissection (ESD) has been widely accepted for selected patients with early gastric cancer (EGC). The aim of this study was to assess the therapeutic outcomes after ESD according to the pathological extent. PATIENTS AND METHODS: From January 2005 to December 2014, a total of 599 patients with 611 lesions were enrolled in this study. The tumors were categorized according to pathological results on the basis of absolute criteria (AC), expanded criteria (EC), EC with undifferentiated histology [(EC-U), mucosal cancer, ulcer (-), ≤20 mm], or beyond EC (BEC). The therapeutic outcomes among the four groups were analyzed retrospectively. RESULTS: The number of patients in the AC, EC, EC-U, and BEC groups was 447, 91, 19, and 54. The complete resection rates of EGC were 97.8, 84.6, 94.4, and 45.5% (P=0.001) and en bloc resection rates in the AC, EC, EC-U, and BEC groups were 99.1, 98.9, 100, and 98.1% (P=0.833), respectively. The 5-year disease-free survival rate in the AC, EC, EC-U, and BEC groups was 90.6, 88.7, 75.0, and 83.3% (P=0.394). In multivariate analysis, undifferentiated histology (P=0.001) and tumor size (>30 mm, P=0.017) were risk factors related to local recurrence. CONCLUSION: The efficacy of ESD for EGCs in EC is almost equal to that in AC when complete resection was achieved. However, the indication for ESD should be decided conservatively because the complete resection rate of EGC in the EC group was significantly lower than that in the AC group. Undifferentiated histology and tumor size over 30 mm were risk factors related to local recurrence.
OBJECTIVES: Endoscopic submucosal dissection (ESD) has been widely accepted for selected patients with early gastric cancer (EGC). The aim of this study was to assess the therapeutic outcomes after ESD according to the pathological extent. PATIENTS AND METHODS: From January 2005 to December 2014, a total of 599 patients with 611 lesions were enrolled in this study. The tumors were categorized according to pathological results on the basis of absolute criteria (AC), expanded criteria (EC), EC with undifferentiated histology [(EC-U), mucosal cancer, ulcer (-), ≤20 mm], or beyond EC (BEC). The therapeutic outcomes among the four groups were analyzed retrospectively. RESULTS: The number of patients in the AC, EC, EC-U, and BEC groups was 447, 91, 19, and 54. The complete resection rates of EGC were 97.8, 84.6, 94.4, and 45.5% (P=0.001) and en bloc resection rates in the AC, EC, EC-U, and BEC groups were 99.1, 98.9, 100, and 98.1% (P=0.833), respectively. The 5-year disease-free survival rate in the AC, EC, EC-U, and BEC groups was 90.6, 88.7, 75.0, and 83.3% (P=0.394). In multivariate analysis, undifferentiated histology (P=0.001) and tumor size (>30 mm, P=0.017) were risk factors related to local recurrence. CONCLUSION: The efficacy of ESD for EGCs in EC is almost equal to that in AC when complete resection was achieved. However, the indication for ESD should be decided conservatively because the complete resection rate of EGC in the EC group was significantly lower than that in the AC group. Undifferentiated histology and tumor size over 30 mm were risk factors related to local recurrence.