The incidence of lymph node metastasis in early gastric cancer according to the expanded criteria in comparison with the absolute criteria of the Japanese Gastric Cancer Association: a systematic review of the literature and meta-analysis

Overall, expanding the indication for endoscopic resection to include mucosal nonulcerated differentiated lesions irrespective of size and differentiated mucosal ulcerated lesions <3 cm is justified with minimal increased risk in comparison to the absolute criteria. However, expanding the indication for undifferentiated lesions ≤2 cm and differentiated lesions with slight submucosal invasion (T1b) should be balanced with the risks of surgery, given the increased risk of LNM in these patients.