The risk of lymph node metastases in 3951 surgically resected mucosal gastric cancers: implications for endoscopic resection.
OBJECTIVE
Endoscopic resection for mucosal gastric cancer (MGC) is highly recommended in the absence of lymph node metastasis (LNM). We aimed to clarify the risk factors for LNM in MGC and to investigate the association of LNM with the indication criteria for endoscopic submucosal dissection (ESD).


METHODS
A retrospective cohort study was performed on 3951 patients with MGC who underwent radical gastrectomy at the Samsung Medical Center in Seoul, Republic of Korea, between September 1994 and September 2010.


RESULTS
Of the patients with MGC, 101 (2.60%) were positive for LNM. Multivariate analysis, followed by univariate analysis, revealed the following risk factors for LNM in MGC: large tumor size, undifferentiated tumor type, lymphatic invasion, perineural invasion, and associated ulceration in the tumor (hazard ratio 1.25, 7.49, 20.65, 23.45, and 4.07, respectively). Patients without LNM had significantly increased survival and/or recurrence-free survival rates than patients with LNM (188.4/209.8 months vs 169.5/188.0 months; P = .029/.004, respectively). Only 3 of 1065 patients (0.3%) who met the absolute indication criteria for ESD had LNM. Of those who met the expanded indication criteria for ESD, 11 of 2678 patients (0.4%) had LNM. LNM also was found in 2 patients who had a differentiated tumor <0.5 cm without ulceration.


CONCLUSIONS
The risk for LNM was very low when patients with MGC met the absolute and/or expanded criteria for endoscopic resection, which meant the indication criteria for ESD was safe and acceptable. However, although the risk for LNM is very low, it should not be considered negligible in endoscopic resection.
Department of Trauma Surgery, Regional Trauma Center, Gachon Gil Hospital, Incheon, Republic of Korea.
Kang Kook
KK
Choi
Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
Jae Moon
JM
Bae
Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
Su Mi
SM
Kim
Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
Tae Sung
TS
Sohn
Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
Jae Hyung
JH
Noh
Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
Jun Ho
JH
Lee
Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
Min-Gew
MG
Choi
Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
Sung
S
Kim
D000230:Adenocarcinoma / Q000556:secondary* / Q000601:surgery*; D000328:Adult; D000368:Aged; D001808:Blood Vessels / Q000473:pathology; D018572:Disease-Free Survival; D004210:Dissection; D005260:Female; D005753:Gastric Mucosa / Q000601:surgery; D005773:Gastroscopy; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D042601:Lymphatic Vessels / Q000473:pathology; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009361:Neoplasm Invasiveness; D012189:Retrospective Studies; D012307:Risk Factors; D013274:Stomach Neoplasms / Q000473:pathology* / Q000601:surgery*; D015996:Survival Rate; D047368:Tumor Burden