Clinicopathological and prognostic differences between mucinous gastric carcinoma and signet-ring cell carcinoma

Objective： To analyze the differences in clinicopathologic characteristics and prognosis between mucinous gastric carcinoma （MGC） and signet-ring cell carcinoma （SRCC）. Methods： Clinicopathologic and prognostic data of 1,637 patients with histologically confirmed MGC or SRCC who received surgical operations in the Department of Gastroenterological Surgery, Beijing Cancer Hospital between December 2004 and December 2009 were retrospectively collected and analyzed. The clinicopathological features were analyzed statistically using Z2 test. Survival was analyzed using the Kaplan- Meier method and multivariate analysis of Cox proportional hazards regression model （backward, stepwise）. Results： A total of 181 patients with gastric cancer （74 MGC, 107 SRCC） were included. MGC, when compared with SRCC, was featured by senile patients, stage III and I~, upper third stomach, large tumor size, positive lymph node metastasis, and positive lymphatic vascular invasion （P〈0.05）. The overall 5-year survival rate showed no difference between the two groups （48.8% vs. 44.8%, P〉0.05）. However, the survival rate for MGC patients was significant lower than that for SRCC patients when compared among the age 〈60 years, negative distant metastasis, and tumor localized at upper third stomach （P〈0.05）. Multivariate Cox proportional hazards models revealed that distant metastasis was a significant independent prognostic indicator in MGC group, and lymph node metastasis and distant metastasis was significant independent prognostic indicators in SRCC group. Conclusions： While compared with SRCC, MGC is associated with a more aggressive tumor biologic behavior. There is no statistically significant difference in distant metastasis, an independent prognostic indicator for both MGC and SRCC, which might be the reason for no significant difference of the overall survival rate between the patients with MGC and SRCC.

Combination of endoscopic submucosal dissection and laparoscopic sentinel lymph node dissection in early mucinous gastric cancer:Role of lymph node metastasis

BACKGROUND Recent evidence showed that combining endoscopic submucosal dissection(ESD)and laparoscopic sentinel lymph node dissection may avoid unnecessary gastrectomy in treating early mucinous gastric cancer(EMGC)patients with risks of positive lymph node metastasis(pLNM).AIM To explore the predictive factors for pLNM in EMGC,and to optimize the clinical application of combing ESD and sentinel lymph node dissection in a proper subgroup of patients with EMGC.METHODS Thirty-one patients with EMGC who had undergone gastrectomy with lymph node dissection were consecutively enrolled from January 1988 to December 2016.Univariate and multivariate logistic regression analyses were used to estimate the association between the rates of pLNM and clinicopathological factors,providing odds ratio(OR)with 95%confidence interval.And the association between the number of predictors and the pLNM rate was also investigated.RESULTS Depth of invasion(OR=7.342,1.127-33.256,P=0.039),tumor diameter(OR=9.158,1.348-29.133,P=0.044),and lymphatic vessel involvement(OR=27.749,1.821-33.143,P=0.019)turned out to be significant and might be the independent risk factors for predicating pLNM in the multivariate analysis.For patients with 1,2,and 3 risk factors,the pLNM rates were 9.1%,33.3%,and 75.0%,respectively.pLNM was not detected in seven patients without any of these risk factors.CONCLUSION ESD might serve as a safe and sufficient treatment for intramucosal EMGC if tumor size≤2 cm,and when lymphatic vessel involvement is absent by postoperative histological examination.Combining ESD and sentinel lymph node dissection could be recommended as a safe and effective treatment for EMGC patients with a potential risk of pLNM.