Published online Oct 21, 2015. doi: 10.3748/wjg.v21.i39.11160
Peer-review started: April 2, 2015
First decision: June 4, 2015
Revised: July 27, 2015
Accepted: August 29, 2015
Article in press: August 29, 2015
Published online: October 21, 2015
Processing time: 200 Days and 11.1 Hours
AIM: To find risk factors of lymph node metastasis (LNM) in early gastric cancer (EGC) and to find proper endoscopic therapy indication in EGC.
METHODS: We retrospectively reviewed the 2270 patients who underwent curative operation for EGC from January 2001 to December 2008. EGC was defined as malignant lesions that do not invade beyond the submucosal layer of the stomach wall irrespective of presence of lymph node metastasis.
RESULTS: Among 2270 enrolled patients, LNM was observed in 217 (9%) patients. LNM in intramucosal (M) cancer and submucosal (SM) cancer was detected in 38 (2.8%, 38/1340) patients and 179 (19%, 179/930) patients, respectively. In univariate analysis, the risk factors for LNM in EGC were size of tumor, Lauren classification, ulcer, lymphatic invasion, vascular invasion, and depth of invasion. However, in multivariate analysis, size of tumor, lymphatic invasion, vascular invasion, and depth of invasion were risk factors for LNM in EGC. Size of tumor, lymphatic invasion, vascular invasion, and depth of invasion were risk factors for LNM in cases of intramucosal cancer and submucosal cancer. In particular, there was no lymph node metastasis in cases of well differentiated early gastric cancer below 1 cm in size without ulcer regardless of lymphovascular invasion.
CONCLUSION: Tumor size, perilymphatic-vascular invasion, and depth of invasion were risk factors for LNM in EGC. There was no LNM in EGC below 1 cm regardless risk factors.
Core tip: Although the depth of tumor infiltration, tumor size as a maximum tumor diameter, and perilymphovascular invasion are independent risk factors for lymph node metastasis (LNM) in early gastric cancer (EGC), there was no LNM in intramucosal cancer which was not signet ring cell type and was below 1 cm without ulceration regardless of lymphatic invasion. This means that endoscopic submucosal dissection can be the treatment of choice in patients with intramucosal cancer below 1 cm without ulceration. There was LN metastasis in EGC of extended criteria in this study. But, the possibility of LNM in intramucosal cancer of extended indication was below 1%.