[Interpretation of Chinese expert consensus on the surgical treatment for adenocarcinoma of esophagogastric junction(2024 edition)]

Due to the unique nature of its anatomical location, the adenocarcinoma of esophagogastric junction (AEG) has been a subject of controversy and disagreement including its definition, staging, and treatment strategies. Chinse expert Consensus on Surgical Treatment of Adenocarcinoma of Esophagogastric Junction in China (2018 Edition) had been released in September 2018 and had played a pioneering role in unifying thoracic and general surgeons in China on surgical treatment strategies for AEG. Over the past five years, the emergence of several clinical research results on AEG has provided new clinical evidence for the selection of key surgical treatment strategies. Therefore, to further standardize the surgical treatment of AEG in China, Chinese Expert Consensus on Surgical Treatment of Adenocarcinoma of Esophagogastric Junction in China (2024 Edition) was released in 2024 by Chinese expert panel including 25 gastrointestinal surgeons and 24 thoracic surgeons. Based on the highest-level clinical research evidence in recent 5 years, this consensus ultimately formulates 29 recommendations on hotspots and key points on surgical treatment of AEG and summary 5 issues that are still awaiting further exploration. This review will provide a summary and detailed interpretation of the recommendations outlined in this consensus.

Development and validation of a nomogram for Siewert II esophagogastric junction adenocarcinoma: a retrospective analysis

Background

Due to the complex histological type and anatomical structures, there has been considerable debate on the classification of adenocarcinoma of the esophagogastric junction (AEG), especially Siewert II AEG. Furthermore, neither the American Joint Committee on Cancer (AJCC) 7th tumor-node-metastasis (TNM) [esophageal adenocarcinoma (E) or gastric cancer (G)] nor the AJCC 8th TNM (E or G) accurately predicted the prognosis of patients with Siewert II AEG.

Objective

This study aimed to investigate the factors influencing the survival and prognosis of patients with Siewert II AEG and establish a new and better prognostic predictive model.

Design

A retrospective study.

Methods

Patients with Siewert II AEG, retrieved from the Surveillance, Epidemiology, and End Results (SEER) databases, were assigned to the training set. Patients retrieved from a single tertiary medical center were assigned to the external validation set. Significant variables were selected using univariate and multivariate Cox regression analyses to construct the nomogram. Nomogram models were assessed using the concordance index (C-index), a calibration plot, decision curve analysis (DCA), and external validation.

Results

Age, tumor grade, and size, as well as the T, N, and M stages, were included in the nomograms. For the SEER training set, the C-index of the nomogram was 0.683 (0.665-0.701). The C-index of the nomogram for the external validation set was 0.690 (0.653-0.727). The calibration curve showed good agreement between the nomogram estimations and actual observations in both the training and external validation sets. The DCA showed that the nomogram was clinically useful.

Conclusion

The new predictive model showed significant accuracy in predicting the prognosis of Siewert II AEG.

[Carbon Emission Characteristics and Influencing Factors of Typical Processes in Drinking Water Treatment Plant]

Based on the actual operating conditions and data monitoring, the carbon emission characteristics of typical processes of a drinking water treatment plant (DWTP) in Tianjin were studied. The total carbon emission intensity measured by CO2-eq was 0.254 kg·m-3, and the proportion of carbon emissions from electricity consumption and reagent consumption was 81.76% and 9.15%, respectively. The key carbon emission sectors of electricity consumption were the water supply pump house, ultrafiltration membrane process, and inlet pump house, which accounted for 50.99%-73.51%, 17.64%-20.70%, and 17.97%-22.40% of the total carbon emission from electricity consumption in the DWTP, respectively. The contribution of sodium hypochlorite to the carbon emission of reagent consumption was 89.12%-90.30%, followed by ferric chloride, PAC, and ammonium sulfate. In the traditional water purification process, the carbon emission intensity of the process unit was in the order of inlet pump house > rapid filter > sedimentation tank. The order in the ultrafiltration membrane advanced treatment process was inlet pump house > ultrafiltration membrane > mechanical coagulation > clarification tank. The carbon emission intensity of the rapid filter process and the ultrafiltration membrane process were 0.070 9 kg·m-3 and 0.109 0 kg·m-3, respectively. The ultrafiltration membrane process could save 23% of the reagent consumption, and its carbon emission of electricity consumption was twice that of the traditional treatment process. The analysis of factors affecting carbon emission in key sectors showed that the raw water quality parameters such as turbidity, pH, ammonia nitrogen, temperature, etc., were significantly correlated with the carbon emission intensity of sodium hypochlorite. There was a significant linear regression relationship between ex-factory water pressure, daily water supply, and carbon emission intensity of the water supply pump house. The control measures of water quality and water pressure can effectively reduce the carbon emissions of the DWTP.

Long-term oncological outcomes of robotic versus laparoscopic gastrectomy for gastric cancer: multicentre cohort study

BACKGROUND

The aim of this multicentre cohort study was to compare the long-term oncological outcomes of robotic gastrectomy (RG) and laparoscopic gastrectomy (LG) for patients with gastric cancer.

METHODS

Patients with gastric cancer who underwent radical gastrectomy by robotic or laparoscopic approaches from 1 March 2010 to 31 December 2018 at 10 high-volume centres in China were selected from institutional databases. Patients receiving RG were matched 1 : 1 by propensity score with patients undergoing LG. The primary outcome was 3-year disease-free survival. Secondary outcomes were overall survival and disease recurrence.

RESULTS

Some 2055 patients who underwent RG and 4309 patients who had LG were included. The propensity score-matched cohort comprised 2026 RGs and 2026 LGs. Median follow-up was 41 (i.q.r. 39-58) months for the RG group and 39 (38-56) months for the LG group. The 3-year disease-free survival rates were 80.8% in the RG group and 79.5% in the LG group (log rank P = 0.240; HR 0.92, 95% c.i. 0.80 to 1.06; P = 0.242). Three-year OS rates were 83.9 and 81.8% respectively (log rank P = 0.068; HR 0.87, 0.75 to 1.01; P = 0.068) and the cumulative incidence of recurrence over 3 years was 19.3% versus 20.8% (HR 0.95, 0.88 to 1.03; P = 0.219), with no difference between groups.

CONCLUSION

RG and LG in patients with gastric cancer are associated with comparable disease-free and overall survival.

Optimal timing of surgery for gastric cancer after neoadjuvant chemotherapy: a systematic review and meta-analysis

BACKGROUND

Following neoadjuvant chemotherapy, surgical resection is one of the most preferred treatment options for locally advanced gastric cancer patients. However, the optimal time interval between chemotherapy and surgery is unclear. This review aimed to identify the optimal time interval between neoadjuvant chemotherapy and surgery for advanced gastric cancer.

METHODS

Beginning on November 12, 2022, we searched the PubMed, Cochrane Library, Web of Science databases, and Embase.com databases for relevant English-language research. Two authors independently screened the studies, assessed their quality, extracted the data, and analyzed the results. The primary goal was to investigate the relationship between the time interval to surgery (TTS) and long-term survival outcomes for patients. This study has been registered with PROSPERO (CRD42022365196).

RESULTS

After an initial search of 4880 articles, the meta-analysis review ultimately included only five retrospective studies. Ultimately, this meta-analysis included 1171 patients, of which 411 patients had TTS of < 4 weeks, 507 patients had TTS of 4-6 weeks, and 253 patients had TTS of > 6 weeks. In survival analysis, patients with TTS of > 6 weeks had poorer overall survival outcomes than patients with TTS of 4-6 weeks (HR = 1.34, 95% CI: 1.03-1.75, P = 0.03). No significant differences were found in terms of disease-free survival the groups.

CONCLUSION

Based on the current clinical evidence, patients with locally advanced gastric cancer may benefit better with a TTS of 4-6 weeks; however, this option still needs additional study.

Helicobacter pylori infection prevalence declined among an urban health check-up population in Chengdu, China: a longitudinal analysis of multiple cross-sectional studies

Objectives

The efficacy of updated health policy in improving the generalization of Helicobacter pylori screening and eradication in southwest China was assessed in a longitudinal analysis of multiple cross-sectional studies from an institution.

Methods

In the periods 2009-2010, 2013-2014, and 2019-2021, 8,365, 16,914, and 18,281 urban observations from health check-ups at West China Hospital were analyzed, respectively. The 14C-urea or 13C-urea breath test was consistently used for H. pylori detection. The protocol has been reported elsewhere (PROSPERO Registration number: CRD42019120764).

Results

The overall prevalence of H. pylori dramatically decreased from 53.1% to 30.7% over the past decade (OR = 0.39, 95% CI 0.37-0.41), with a similar decline in all sex-specific and age-specific subgroups. The age-specific prevalence consistently increased before 40 years of age and always peaked at 50-59 years. Longitudinal clearance increased along with aging, and prevalence dropped to 22.6%, 25.1%, and 23.6% in the 40-49, 50-59, and 60-69 years initial age groups, respectively.

Conclusion

The generalization of H. pylori screening and eradication could greatly contribute to the control of H. pylori infection among urban health check-up populations and lower gastric cancer incidence.

Incidence of cancer for patients after bariatric surgery: evidence from 33 cohort studies

BACKGROUND

With the rising prevalence of severe obesity, bariatric surgery has emerged as a crucial treatment option. As the number of surgeries performed worldwide increases, there has been growing interest in the impact of bariatric surgery on cancer incidence. While several studies have examined this relationship, the topic remains controversial.

OBJECTIVES

We conducted this systematic review of cohort studies with meta-analysis to evaluate the effect of bariatric surgery versus nonsurgical treatment on overall cancer incidence. However, the effects may vary when focusing on specific cancer types, surgical procedures, or gender, so we conducted additional subgroup analyses.

SETTING

A meta-analysis. University hospital.

METHODS

The Cochrane, Embase, PubMed, and Web of Science databases were searched for studies from 1 January 2000 to 1 December 2022. Meta-analysis was conducted to evaluate the pooled effect and further implemented subgroup analysis stratified by cancer type, operation type, and sex.

RESULTS

All cohort studies were included in this meta-analysis from 18,216 studies. The overall cancer incidence demonstrated a significant decrease in the group with bariatric surgery (odds ratios [OR] = .56, P = .000, 95% CI .46 to .68). In subgroup analysis, similar decrease effect was found in 9 cancers. Furthermore, the incidence of cancer decreased significantly in male (OR = .66, P = .001, 95% CI .51 to .85) and female patients (OR = .63, P = .000, 95% CI .57 to .69) and patients undergoing gastric bypass (OR = .46, P = .000, 95% CI .33 to .63) or sleeve gastrectomy (OR = .44, P = .001, 95% CI .27 to .70).

CONCLUSIONS

In the overall analysis, bariatric surgery could reduce the incidence of cancer significantly. Further large-scale well-matched studies are needed to verify the protective effect of bariatric surgery on cancer incidence.

Association between circulating tumor cells in the peripheral blood and the prognosis of gastric cancer patients: a meta-analysis

Background

Research on the correlation between circulating tumor cells (CTCs) and gastric cancer (GC) has increased rapidly in recent years. However, whether CTCs are associated with GC patient prognosis is highly controversial.

Objective

This study aims to evaluate the value of CTCs to predict the prognosis of GC patients.

Design

A meta-analysis.

Data Sources and Methods

We searched the PubMed, Embase, and Cochrane Library databases for studies that reported the prognostic value of CTCs in GC patients before October 2022. The association between CTCs and overall survival (OS) and disease-free survival (DFS)/recurrence-free survival (RFS) and progression-free survival (PFS) of GC patients was assessed. Subgroup analyses were stratified by sampling times (pre-treatment and post-treatment), detection targets, detection method, treatment method, tumor stage, region, and HR (Hazard Ratio) extraction methods. Sensitivity analysis was performed by removing individual studies to assess the stability of the results. Publication bias was evaluated using funnel plots, Egger's test, and Begg's test.

Results

We initially screened 2000 studies, of which 28 were available for further analysis, involving 2383 GC patients. The pooled analysis concluded that the detection of CTCs was associated with poor OS (HR = 1.933, 95% CI 1.657-2.256, p < 0.001), DFS/RFS (HR = 3.228, 95% CI 2.475-4.211, p < 0.001), and PFS (HR = 3.272, 95% CI 1.970-5.435, p < 0.001). Furthermore, the subgroup analysis stratified by tumor stage (p < 0.01), HR extraction methods (p < 0.001), detection targets (p < 0.001), detection method (p < 0.001), sampling times (p < 0.001), and treatment method (p < 0.001) all showed that CTC detection was associated with poor OS and DFS/RFS for GC patients. Furthermore, the study showed that CTCs were associated with the poor DFS/RFS of GC when CTCs were detected for patients from Asian or No-Asian regions (p < 0.05). In addition, higher CTCs predicted poorer OS for GC patients who are from Asian regions (p < 0.001), but without statistical difference for GC patients from No-Asian regions (p = 0.490).

Conclusion

CTC detection in peripheral blood was associated with poor OS, DFS/RFS, and PFS in patients with GC.

[Clinicopathological characteristics and prognosis of patients with small bowel tumors: A single center analysis of 220 cases]

Objective: To analyze the clinicopathological characteristics and prognosis of patients with small bowel tumors. Methods: This was a retrospective, observational study. We collected clinicopathological data of patients with primary jejunal or ileal tumors who had undergone small bowel resection in the Department of Gastrointestinal Surgery, West China Hospital, Sichuan University between January 2012 and September 2017. The inclusion criteria included: (1) older than 18 years; (2) had undergone small bowel resection; (3) primary location at jejunum or ileum; (4) postoperative pathological examination confirmed malignancy or malignant potential; and (5) complete clinicopathological and follow-up data. Patients with a history of previous or other concomitant malignancies and those who had undergone exploratory laparotomy with biopsy but no resection were excluded. The clinicopathological characteristics and prognoses of included patients were analyzed. Results: The study cohort comprised 220 patients with small bowel tumors, 136 of which were classified as gastrointestinal stromal tumors (GISTs), 47 as adenocarcinomas, and 35 as lymphomas. The median follow-up for all patient was 81.0 months (75.9-86.1). GISTs frequently manifested as gastrointestinal bleeding (61.0%, 83/136) and abdominal pain (38.2%, 52/136). In the patients with GISTs, the rates of lymph node and distant metastasis were 0.7% (1/136) and 11.8% (16/136), respectively. The median follow-up time was 81.0 (75.9-86.1) months. The 3-year overall survival (OS) rate was 96.3%. Multivariate Cox regression-analysis results showed that distant metastasis was the only factor associated with OS of patients with GISTs (HR=23.639, 95% CI: 4.564-122.430, P<0.001). The main clinical manifestations of small bowel adenocarcinoma were abdominal pain (85.1%, 40/47), constipation/diarrhea (61.7%, 29/47), and weight loss (61.7%, 29/47). Rates of lymph node and distant metastasis in patients with small bowel adenocarcinoma were 53.2% (25/47) and 23.4% (11/47), respectively. The 3-year OS rate of patients with small bowel adenocarcinoma was 44.7%. Multivariate Cox regression-analysis results showed that distant metastasis (HR=4.018, 95%CI: 2.108-10.331, P<0.001) and adjuvant chemotherapy (HR=0.291, 95% CI: 0.140-0.609, P=0.001) were independently associated with OS of patients with small bowel adenocarcinoma. Small bowel lymphoma frequently manifested as abdominal pain (68.6%, 24/35) and constipation/diarrhea (31.4%, 11/35); 77.1% (27/35) of small bowel lymphomas were of B-cell origin. The 3-year OS rate of patients with small bowel lymphomas was 60.0%. T/NK cell lymphomas (HR= 6.598, 95% CI: 2.172-20.041, P<0.001) and adjuvant chemotherapy (HR=0.119, 95% CI: 0.015-0.925, P=0.042) were independently associated with OS of patients with small bowel lymphoma. Small bowel GISTs have a better prognosis than small intestinal adenocarcinomas (P<0.001) or lymphomas (P<0.001), and small bowel lymphomas have a better prognosis than small bowel adenocarcinomas (P=0.035). Conclusions: The clinical manifestations of small intestinal tumor are non-specific. Small bowel GISTs are relatively indolent and have a good prognosis, whereas adenocarcinomas and lymphomas (especially T/NK-cell lymphomas) are highly malignant and have a poor prognosis. Adjuvant chemotherapy would likely improve the prognosis of patients with small bowel adenocarcinomas or lymphomas.

Role of the gut microbiota in anticancer therapy: from molecular mechanisms to clinical applications

In the past period, due to the rapid development of next-generation sequencing technology, accumulating evidence has clarified the complex role of the human microbiota in the development of cancer and the therapeutic response. More importantly, available evidence seems to indicate that modulating the composition of the gut microbiota to improve the efficacy of anti-cancer drugs may be feasible. However, intricate complexities exist, and a deep and comprehensive understanding of how the human microbiota interacts with cancer is critical to realize its full potential in cancer treatment. The purpose of this review is to summarize the initial clues on molecular mechanisms regarding the mutual effects between the gut microbiota and cancer development, and to highlight the relationship between gut microbes and the efficacy of immunotherapy, chemotherapy, radiation therapy and cancer surgery, which may provide insights into the formulation of individualized therapeutic strategies for cancer management. In addition, the current and emerging microbial interventions for cancer therapy as well as their clinical applications are summarized. Although many challenges remain for now, the great importance and full potential of the gut microbiota cannot be overstated for the development of individualized anti-cancer strategies, and it is necessary to explore a holistic approach that incorporates microbial modulation therapy in cancer.

A Gastrectomy for early-stage gastric cancer patients with or without preserving celiac branches of vagus nerves: A meta-analysis

BACKGROUND

Vagus nerve-preserving gastrectomy is increasingly popular in treating gastric cancer in the early stage, however the long and short-term outcomes after gastrectomy while preserving the celiac branch of the vagus nerve are not well defined. We aimed to summarize and compare perioperative and longer-term outcomes after celiac branch vagus nerve-preserving gastrectomy (CBP, preserving both the celiac and hepatic branches of the vagus nerve), compared to those without CBP (non-CBP, only the hepatic branch of the vagus nerve is preserved).

METHODS

We searched the Embase, PubMed, Cochrane Library and Web of Science databases for papers published before October 2021. The primary results were evaluated by short-term and long-term postoperative complications, whereas the secondary outcomes included surgery-related parameters, recovery-related parameters and overall survival. Random-effects or fixed-effects model were used to estimate odds ratio, and weighted mean difference for the outcomes. The underlying publication bias was identified via funnel charts, Begg's test and Egger's test. Sensitivity analysis was conducted by removing the research one by one.

RESULTS

A total of 9 studies consisting of 8 retrospective studies and one randomized control trial were included. The analysis included 1,109 patients, with 568 (51.2%) of patients receiving CBP and 541 (48.8%) patients who received non-CBP. The CBP group had a shorter time in terms of first flatus (weighted mean difference = -0.436, 95% confidence interval: -0.603 to -0.269; P < 0.001) and hospital stay (weighted mean difference = -0.456, 95% confidence interval: -0.874 to -0.037, P = 0.033) than the non-CBP group, but the time to the start of oral intake was comparable between the groups. Regarding short-term complications and surgery-related parameters, between CBP and non-CBP, no evident differences were observed in pancreatic complications, anastomotic leakage, postoperative bleeding, operation time, blood loss or lymph nodes examined. In terms of long-term complications, the incidence of gallstones in CBP was lower than that in non-CBP (odds ratio = 0.582, 95% confidence interval: 0.356-0.953, P = 0.031), and the incidence of bile reflux in CBP was lower than that in non-CBP (odds ratio = 0.473, 95% confidence interval: 0.280-0.800, P = 0.005). However, the prevalence rates of diarrhea, early dumping syndrome, esophageal reflux, and delayed gastric emptying were comparable between CBP and non-CBP.

CONCLUSION

The present research showed that gastric cancer patients in the early stage under CBP were superior to those without CBP in terms of incidence of gallstones, bile reflux, time of first flatus and hospital stay. Furthermore, it is imperative to conduct randomized control studies with larger sample sizes to determine the oncological survival outcomes when preserving the celiac branch.

Is No. 12a Lymph Node Dissection Compliance Necessary in Patients Who Undergo D2 Gastrectomy for Gastric Adenocarcinomas? A Population-Based Retrospective Propensity Score Matching Study

LN dissection is essential for accurately staging and improving GC patient prognosis. However, the compliance rate for No. 12a LND in practice is low, and its necessity is controversial. Data from GC patients who underwent total gastrectomy (TG)/distal gastrectomy (DG) plus D2 lymphadenectomy between January 2000 and December 2017 at West China Hospital, Sichuan University were reviewed. No. 12a LND noncompliance's effect on the long-term prognosis of patients with GC after D2 gastrectomy was explored. Of the 2788 patients included, No. 12a LND noncompliance occurred in 1753 patients (62.9%). Among 1035 patients with assessable LNs from station 12a, 98 (9.5%) had positive LNs detected at station 12a. No. 12a LN metastasis patients (stage IV not included) had significantly better overall survival (OS) than TNM stage IV patients (p = 0.006). Patients with No. 12a LND compliance had a significantly higher OS than those without, both before (p < 0.001) and after (p < 0.001) PSM. Cox multivariate analysis confirmed that No. 12a LND noncompliance was an independent prognostic factor before (HR 1.323, 95% CI 1.171-1.496, p < 0.001) and after (HR 1.353, 95% CI 1.173-1.560, p < 0.001) PSM. In conclusion, noncompliance with No. 12a LND compromised the long-term survival of patients who underwent D2 gastrectomy for GC.

The role and mechanism of claudins in cancer

Claudins are a tetraspan membrane protein multigene family that plays a structural and functional role in constructing tight junctions. Claudins perform crucial roles in maintaining cell polarity in epithelial and endothelial cell sheets and controlling paracellular permeability. In the last two decades, increasing evidence indicates that claudin proteins play a major role in controlling paracellular permeability and signaling inside cells. Several types of claudins are dysregulated in various cancers. Depending on where the tumor originated, claudin overexpression or underexpression has been shown to regulate cell proliferation, cell growth, metabolism, metastasis and cell stemness. Epithelial-to-mesenchymal transition is one of the most important functions of claudin proteins in disease progression. However, the exact molecular mechanisms and signaling pathways that explain why claudin proteins are so important to tumorigenesis and progression have not been determined. In addition, claudins are currently being investigated as possible diagnostic and treatment targets. Here, we discuss how claudin-related signaling pathways affect tumorigenesis, tumor progression, and treatment sensitivity.

Prevalence Difference of Helicobacter pylori Infection Between Tibetan and Han Ethnics in China: A Meta-analysis on Epidemiologic Studies (SIGES)

China is a multi-ethnic country, and the prevalence of Helicobacter pylori ( H pylori) infection may be diverse among ethnics. This meta-analysis was conducted to compare the prevalence of H pylori infection between Tibetans and Han ethnics. Ten studies that reported the prevalence of H pylori infection between Tibetans and Hans in China were eligible. The pooled prevalence of H pylori infection was 62.2% versus 55.3% among Tibetans and Hans, respectively. Tibetans had a higher risk of H pylori infection than Hans (odds ratio [OR] = 1.38, 95% confidence interval [CI] [1.05, 1.80]). In subgroup analysis, Tibetans with upper gastrointestinal symptoms (OR = 1.51, 95% CI [1.06-2.16]), inhabiting in Tibet (OR = 1.51, 95% CI [1.22, 1.87]), or inhabiting in Northwestern region (OR = 1.15, 95% CI [1.00, 1.31]) had significantly higher risks of H pylori infection. In addition, in the recent 10 years, Hans showed a decreased risk of H pylori infection (OR = 1.81, 95% CI [1.42, 2.30]). Heterogeneity was common, while sensitivity analyses showed partially inconsistent results against main findings. This study demonstrated higher prevalence of H pylori infection in Tibetans compared with Hans, especially in recent years, or in Tibet and northwest China, as well as symptomatic Tibetans. The results suggest tailored strategy and robustness need to be further considered for H pylori screening and eradication among Tibetans.

[How to master the clinical study on digestive tract reconstruction in gastric cancer surgery]

Digestive tract reconstruction is extremely important during gastric cancer surgery, which is related to long-tern quality of life of patients. The selection of reconstruction methods and the application of reconstruction techniques are major topics in the field of reconstruction-related study of gastric cancer surgery. The clinical research on digestive tract reconstruction needs to be designed and implemented scientifically to comprehensively evaluate the impact of reconstruction methods on surgical safety, long-term survival outcomes, short- and long-term changes in quality of life, endoscopic mucosal changes and postoperative nutritional status. In addition, health economic analysis is also important and should be considered in reconstruction-related studies. In brief, selection of appropriate gastrointestinal reconstruction methods based on individual characteristics of each gastric cancer patients may be an important direction of clinical trials in the future.

[Comparison of postoperative mid-term and long-term quality of life between Billroth-I gastroduodenostomy and Billroth-II gastrojejunostomy after radical distal gastrectomy in patients with gastric cancer: a cohort study based on a case registry database]

Objective: The pattern of digestive tract reconstruction in radical gastrectomy for gastric cancer is still inconclusive. This study aims to compare mid-term and long-term quality of life after radical gastrectomy for distal gastric cancer between Billroth-I (B-I) and Billroth-II (B-II) reconstruction. Methods: A retrospective cohort study was conducted.Clinicopathological and follow-up data of 859 gastric cancer patients were colected cellected from the surgical case registry database of Gastrointestinal Surgery Center of Sichuan University West China Hospital, who underwent radical distal gastric cancer resection between January 2016 and December 2020. Inclusion criteria: (1) gastric cancer confirmed by preoperative gastroscopy and biopsy; (2) elective radical distal major gastrectomy performed according to the Japanese Society for Gastric Cancer treatment guidelines for gastric cancer; (3) TNM staging referenced to the American Cancer Society 8th edition criteria and exclusion of patients with stage IV by postoperative pathology; (4) combined organ resection only involving the gallbladder or appendix; (5) gastrointestinal tract reconstruction modality of B-I or B-II; (6) complete clinicopathological data; (7) survivor during the last follow-up period from December 15, 2021 to January 15, 2022. Exclusion criteria: (1) poor compliance to follow-up; (2) incomplete information on questionnaire evaluation; (3) survivors with tumors; (4) concurrent malignancies in other systems; (5) concurrent psychiatric and neurological disorders that seriously affected the objectivity of the questionnaire or interfered with patient's cognition. Telephone follow-up was conducted by a single investigator from December 2021 to January 2022, and the standardized questionnaire EORTC QLQ-C30 scale (symptom domains, functional domains and general health status) and EORTC QLQ-STO22 scale (5 symptoms of dysphagia, pain, reflux, restricted eating, anxiety; 4 single items of dry mouth, taste, body image, hair loss) were applied to evaluate postoperative quality of life. In 859 patients, 271 were females and 588 were males; the median age was 57.0 (49.5, 66.0) years. The included cases were divided into the postoperative follow-up first year group (202 cases), the second year group (236 cases), the third year group (148 cases), the fourth year group (129 cases) and the fifth year group (144 cases) according to the number of years of postoperative follow-up. Each group was then divided into B-I reconstruction group and B-II reconstruction group according to procedure of digestive tract reconstruction. Except for T-stage in the fourth year group, and age, tumor T-stage and tumor TNM-stage in the fifth year group, whose differences were statistically significant between the B-I and B-II reconstruction groups (all P<0.05), the differences between the B-I and B-II reconstruction groups in terms of demographics, body mass index (BMI), tumor TNM-stage and tumor pathological grading in postoperative follow-up each year group were not statistically significant (all P>0.05), suggesting that the baseline information between B-I reconstruction group and the B-II reconstruction group in postoperative each year group was comparable. Evaluation indicators of quality of life (EORTC QLQ-C30 and EORTC QLQ-STO22 scales) and nutrition-related laboratory tests (serum hemoglobin, albumin, total protein, triglycerides) between the B-I reconstruction group and B-II reconstruction group in each year group were compared. Non-normally distributed continuous variables were presented as median (Q(1),Q(3)), and compared by using the Wilcoxon rank sum test (paired=False). The χ(2) test or Fisher's exact test was used for comparison of categorical variables between groups. Results: There were no statistically significant differences in all indexes EORTC QLQ-30 scale between the B-I reconstruction group and the B-II reconstruction group among all postoperative follow-up year groups (all P>0.05). The EORTC QLQ-STO22 scale showed that significant differences in pain and eating scores between the B-I reconstruction group and the B-II reconstruction group were found in the second year group, and significant differences in eating, body and hair loss scores between the B-I reconstruction group and the B-II reconstruction group were found in the third year group (all P<0.05), while no significant differences of other item scores between the B-I reconstruction group and the B-II reconstruction group were found in postoperative follow-up of all year groups (P>0.05). Triglyceride level was higher in the B-II reconstruction group than that in the B-I reconstruction group (W=2 060.5, P=0.038), and the proportion of patients with hyperlipidemia (triglycerides >1.85 mmol/L) was also higher in the B-II reconstruction group (19/168, 11.3%) than that in the B-I reconstruction group (0/34) (χ(2)=0.047, P=0.030) in the first year group with significant difference. Albumin level was lower in the B-II reconstruction group than that in the B-I reconstruction group (W=482.5, P=0.036), and the proportion of patients with hypoproteinemia (albumin <40 g/L) was also higher in the B-II reconstruction group (19/125, 15.2%) than that in the B-I reconstruction group (0/19) in the fifth year group, but the difference was not statistically significant (χ(2)=0.341, P=0.164). Other nutrition-related clinical laboratory tests were not statistically different between the B-I reconstruction and the B-II reconstruction in each year group (all P>0.05). Conclusions: The effects of both B-I and B-II reconstruction methods on postoperative mid-term and long-term quality of life are comparable. The choice of reconstruction method after radical resection of distal gastric cancer can be based on a combination of patients' condition, sugenos' eoperience and operational convenience.

[Clinical significance of No.11p posterior lymph nodes dissection in gastric cancer surgery]

Objective: To analyze the association of No.11p posterior lymph node metastasis with clinicopathological features and its prognostic significance in gastric cancer. Methods: A single-center retrospective cohort study was conducted. Clinicopathological data of patients with primary gastric cancers undergoing No.11p posterior lymph node dissection from January 2016 to December 2020 were retrieved from the Database of Gastric Cancer, West China Hospital, Sichuan University. Case inclusion criteria: (1) gastric cancer proved by pathology; (2) radical resection with intraoperative No.11p posterior lymph node dissection; (3) operations performed by the same surgical team; (4) no previous history of other malignant tumors and no concurrent malignant tumors. Those with stump gastric cancer, history of gastrectomy, neoadjuvant chemotherapy, incomplete clinicopathological data and lost to follow-up were excluded. During the operation, the upper edge of the pancreas was retracted forward to expose the area between the upper edge of the pancreas and the splenic vessels. The proximal segment of the splenic artery was skeletonized to remove lymphatic tissue anterior and superior to the splenic artery for No.11p lymph node dissection. For patients with lymphadenopathy in the area between the splenic artery and the splenic vein, dissection was performed. The enlarged lymph nodes were labeled with titanium clips and named as No.11p posterior lymph node. Pathological examination was performed separately after the specimen was isolated. Statistical analysis was performed using R software. Results: A total of 127 gastric cancer patients, who underwent No.11p posterior lymph nodes dissection were included in this study, of which 120 patients without No.11p posterior lymph nodes metastasis (No.11p posterior lymph nodes negative) and 7 patients with No.11p posterior lymph nodes metastasis (No.11p posterior lymph nodes positive). A total of 8 metastatic No.11p posterior lymph nodes were detected in 7 patients, metastasis rate and with a ratio of 5.5% (7/127) and 6.8% (8/127), respectively. In the subgroup analysis of T3-4 stage patients, the metastasis rate and ratio of No.11p posterior lymph nodes were 9.0% (7/78) and 10.7% (8/75), respectively. Compared to negative cases, patients with No.11p posterior lymph nodes metastasis had larger tumor (P=0.002), higher proportion of Borrmann type Ⅲ and Ⅳ tumors (P=0.005), more metastatic lymph nodes (P<0.001), more advanced T stage (P=0.043), N stage (P=0.004) and TNM stage (P=0.015). In survival analysis, patients with No.11p posterior lymph node metastasis had a significantly worse prognosis than those without metastasis after adjusting for TNM stage (hazard ratio=3.009, 95% confidence interval: 1.824-4.964, P<0.001). Conclusions: The No.11p posterior lymph node metastasis in gastric cancer is associated with worse prognosis. For patients of T3-4 stage gastric cancer, No.11p posterior lymph node dissection should be emphasized during radical operation.

Genomic evolution and diverse models of systemic metastases in colorectal cancer

OBJECTIVE

The systemic spread of colorectal cancer (CRC) is dominated by the portal system and exhibits diverse patterns of metastasis without systematical genomic investigation. Here, we evaluated the genomic evolution of CRC with multiorgan metastases using multiregion sequencing.

DESIGN

Whole-exome sequencing was performed on multiple regions (n=74) of matched primary tumour, adjacent non-cancerous mucosa, liver metastasis and lung metastasis from six patients with CRC. Phylogenetic reconstruction and evolutionary analyses were used to investigate the metastatic seeding pattern and clonal origin. Recurrent driver gene mutations were analysed across patients and validated in two independent cohorts. Metastatic assays were performed to examine the effect of the novel driver gene on the malignant behaviour of CRC cells.

RESULTS

Based on the migration patterns and clonal origins, three models were revealed (sequential, branch-off and diaspora), which not only supported the anatomic assumption that CRC cells spread to lung after clonally expanding in the liver, but also illustrated the direct seeding of extrahepatic metastases from primary tumours independently. Unlike other cancer types, polyphyletic seeding occurs in CRC, which may result in late metastases with intermetastatic driver gene heterogeneity. In cases with rapid dissemination, we found recurrent trunk loss-of-function mutations in ZFP36L2, which is enriched in metastatic CRC and associated with poor overall survival. CRISPR/Cas9-mediated knockout of ZFP36L2 enhances the metastatic potential of CRC cells.

CONCLUSION

Our results provide genomic evidence for metastatic evolution and indicate that biopsy/sequencing of metastases may be considered for patients with CRC with multiorgan or late postoperative metastasis.

Nomogram to Predict Intensive Care Following Gastrectomy for Gastric Cancer: A Useful Clinical Tool to Guide the Decision-Making of Intensive Care Unit Admission

BACKGROUND

We aimed to generate and validate a nomogram to predict patients most likely to require intensive care unit (ICU) admission following gastric cancer surgery to improve postoperative outcomes and optimize the allocation of medical resources.

METHODS

We retrospectively analyzed 3,468 patients who underwent gastrectomy for gastric cancer from January 2009 to June 2018. Here, 70.0% of the patients were randomly assigned to the training cohort, and 30.0% were assigned to the validation cohort. Least absolute shrinkage and selection operator (LASSO) method was performed to screen out risk factors for ICU-specific care using the training cohort. Then, based on the results of LASSO regression analysis, multivariable logistic regression analysis was performed to establish the prediction nomogram. The calibration and discrimination of the nomogram were evaluated in the training cohort and validated in the validation cohort. Finally, the clinical usefulness was determined by decision curve analysis (DCA).

RESULTS

Age, the American Society of Anesthesiologists (ASA) score, chronic pulmonary disease, heart disease, hypertension, combined organ resection, and preoperative and/or intraoperative blood transfusions were selected for the model. The concordance index (C-index) of the model was 0.843 in the training cohort and 0.831 in the validation cohort. The calibration curves of the ICU-specific care risk nomogram suggested great agreement in both training and validation cohorts. The DCA showed that the nomogram was clinically useful.

CONCLUSIONS

Age, ASA score, chronic pulmonary disease, heart disease, hypertension, combined organ resection, and preoperative and/or intraoperative blood transfusions were identified as risk factors for ICU-specific care after gastric surgery. A clinically friendly model was generated to identify those most likely to require intensive care.

Assessment of indocyanine green fluorescence lymphography on lymphadenectomy during minimally invasive gastric cancer surgery: a systematic review and meta-analysis

BACKGROUND

In recent years, indocyanine green fluorescence lymphography has been introduced for lymphatic mapping in gastric cancer surgery. The aim of this study was to investigate the efficacy of ICGFL in lymph node dissection during minimally invasive surgery for gastric cancer.

METHODS

A systematic review of electronic databases including PubMed, Embase, Web of Science, the Cochrane Library, and China National Knowledge Infrastructure was performed from the inception to January 2021 for all studies comparing ICGFL with non-ICGFL in GC patients undergoing minimal access gastrectomy. The primary outcome was the total number of harvested lymph nodes. The secondary endpoints were the number of metastatic LNs, operative time, estimated blood loss, and postoperative complications. The registration number of this protocol is PROSPERO CRD42020203443.

RESULTS

A total of 13 studies including 1882 participants were included. In this meta-analysis, the use of ICGFL was associated with a higher number of harvested LNs (40.33 vs. 33.40; MD = 6.93; 95%CI: 4.28 to 9.58; P < 0.0001; I² = 86%). No significant difference was found between the ICGFL and control groups in terms of metastatic LNs (2.63 vs. 2.42; MD = 0.21; 95%CI: -0.46 to 0.87; P = 0.54; I² = 0%). In addition, the use of ICGFL could be safely performed without increasing the operative time (P = 0.49), estimated blood loss (P = 0.26) and postoperative complications (P = 0.54).

CONCLUSION

The use of ICGFL may be a useful tool facilitating complete lymph node dissection during minimally invasive GC resection. However, more high-quality RCTs with large sample size are needed to validate this issue.

Comparison of Survival and Safety Between Total Omentectomy and Partial Omentectomy for Gastric Cancer: A Meta-Analysis

Background: The greater omentum can limit abdominal inflammation and act as a protective cushion, but it is always involved in dissemination of gastric cancer. The purpose of this meta-analysis was to compare the survival and safety between total omentectomy and partial omentectomy for gastric cancer.

Methods: Two investigators independently conducted a systematic search of PubMed, Embase, CNKI, and Cochrane Library ranging from January 2000 to November 2020. The pooled odds ratio (ORs) and weighted mean difference (WMD) with the 95% confidence interval (95% CI) were used to assess perioperative and survival parameters.

Results: A total of 2,031 patients in 11 studies (574 patients in the partial omentectomy group and 1,457 patients in the total omentectomy group) were included. The results found shorter operation time (WMD = −25.584; P = 0.000) and less intraoperative blood loss (WMD = −47.301; P = 0.050) in the partial omentectomy group, compared to total omentectomy. There were no significant differences in terms of incidence of complications (OR = 0.770; P = 0.164), blood transfusions rates (OR = 0.269; P = 0.161), time to first flatus (WMD = 0.160; P = 0.345), hospital stay (WMD = −1.258; P = 0.087), and number of harvested lymph nodes (WMD = 1.265; P = 0.662). For the disease-free survival (OR = 0.80; P = 0.381) and overall survival, there were no statistical differences between the two procedures.

Conclusions: The partial omentectomy could reduce operation time and trended to decrease intraoperative blood loss. And the survival in patients with partial omentectomy seemed to be comparable to that of patients with total omentectomy.

Application of Gross Tissue Response System in Gastric Cancer After Neoadjuvant Chemotherapy: A Primary Report of a Prospective Cohort Study

OBJECTIVE

We previously established a gross tissue response (GTR) system to evaluate the intraoperative response of perigastric tissue in patients with gastric cancers to neoadjuvant chemotherapy. This prospective cohort study aims to confirm the relationship between gross tissue response and clinicopathological characteristics and explore the possibility of using the GTR system to predict the difficulty of surgery and the occurrence of postoperative complications within 30 days.

METHODS

A total of 102 patients with gastric cancer from January 2019 to April 2020 were enrolled in this study. The degrees of fibrosis, edema, and effusion in the perigastric tissues were assessed intraoperatively according to the GTR system. We systematically analyzed the relations between GTR and clinicopathological characteristics, and then a prediction model that includes GTR was established to predict the difficulty of surgery and the occurrence of postoperative complications within 30 days.

RESULTS

Finally, the study included 71 male patients and 31 female patients. The patients had an average age of 58.79 ± 1.03 years, BMI of 22.89 ± 0.29, and tumor diameter of 4.50 ± 0.27 cm. Among these patients, 17 underwent laparoscopic gastrectomy, 85 underwent open gastrectomy, the average operation time was 294.63 ± 4.84 minutes, and the mean volume of intraoperative blood loss was 94.65 ± 5.30 ml. The overall 30-day postoperative complication rate was 19.6% (20/102). The total GTR was significantly related to the primary tumor stage, operation time and 30-day postoperative complication rate (p<0.05). Edema and effusion were significantly related to intraoperative blood loss (p<0.05). The logistic regression analysis identified that the total GTR score (score: 4-9, OR 2.888, 95% CI: 1.035-8.062, p = 0.043) was an independent risk factor for postoperative complications within 30 days, and the total GTR score (score 4-9, OR 3.32, 95% CI 1.219-9.045, p=0.019) was also an independent risk factor for operation time. The AUC of the total GTR score for predicting postoperative complications within 30 days was 0.681.

CONCLUSION

According to the results of the present study, the gross tissue response (GTR) system is an effective tool that may be used to predict the risk of a difficult operation after neoadjuvant chemotherapy and postoperative complications. Although neoadjuvant chemotherapy improves the therapeutic effect, it also increases the risk of surgical trauma and postoperative complications.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, identifier NCT03791268.

Clinical significance of lower perigastric lymph nodes dissection in Siewert type II/III adenocarcinoma of esophagogastric junction: a retrospective propensity score matched study

PURPOSE

The optimal surgical procedure, whether total gastrectomy (TG) or proximal gastrectomy (PG), for Siewert type II/III adenocarcinoma of esophagogastric junction (AEG) has not been standardised, primarily because the optimal extent of lymph node (LN) dissection for AEG based on the metastatic rate of perigastric LNs remains under debate. The aim of this study was to investigate the metastatic incidence and prognostic significance of lower perigastric lymph nodes (LPLN), including No.4d, 5, 6 and 12a LN stations, in Siewert type II/III AEG.

METHODS

A total of 701 patients with Siewert type II/III AEG who received transabdominal open gastrectomy (425 patients with TG and 276 patients with PG) from 2010 to 2015 in West China Hospital were retrospectively included. Based on the clinicopathological information of TG patients, the risk factors of LPLN-positive patients were evaluated, and the metastatic incidence as well as the therapeutic value (TV) index of each LN station was assessed. Moreover, the 5-year overall survival (OS) rates between LPLN-positive and LPLN-negative groups were compared in TG patients, and the postoperative survival difference between TG and PG patients was also compared, using propensity score matching (PSM) method.

RESULTS

Tumour size (≥ 5 cm, OR = 1.481, p = 0.002) and pT stage (pT4, OR = 2.755, p = 0.024) were significant risk factors for patients with LPLN metastasis. For patients with tumour size more than 5 cm or pT4 stage, the metastatic rates of LPLN for Siewert type II, III and II/III AEG were 31.67%, 34.69% and 33.03%, whereas the TV indexes of LPLN for them were 5.76, 5.62 and 5.38, respectively. LPLN was a significant independent prognostic factor (HR = 1.422, p = 0.028), and positive LPLN was related to worse prognosis (p < 0.05). For patients with tumour size more than 5 cm or pT4 stage, TG patients were illustrated to have a better prognosis than PG patients, with 5-year OS rates of 58.9% vs 38.2% for Siewert type II AEG (χ2 = 4.159, p = 0.041), 68.9% vs 50.2% for Siewert type III AEG (χ2 = 5.630, p = 0.018) and 65.1% vs 40.3% for Siewert type II/III AEG (χ2 = 12.604, p < 0.001), respectively.

CONCLUSIONS

LPLN metastasis is a poor prognostic factor for patients with Siewert II/III AEG. LPLN dissection may improve the long-term survival of patients with tumour size more than 5 cm or pT4 stage, and TG might be more suitable for this kind of cancer.

The long-term survival outcomes of gastric cancer patients with total intravenous anesthesia or inhalation anesthesia: a single-center retrospective cohort study

Background

The relationship between the type of anesthesia and the survival outcomes of gastric cancer patients is uncertain. This study compared the overall outcome of gastric cancer patients after surgery with total intravenous anesthesia (TIVA) or inhalation anesthesia (IHA).

Methods

Clinicopathological variables of gastric cancer patients were retrieved from the database of the Surgical Gastric Cancer Patient Registry in West China Hospital, Sichuan University. Patients were grouped according to whether they received TIVA or IHA during the operation. Propensity score (PS) matching was used to balance the baseline variables, and survival outcomes were compared between these two groups. In addition, studies comparing survival outcomes between TIVA and IHA used for gastric cancer surgery and published before April 20th, 2020, were identified, and their data were pooled.

Results

A total of 2827 patients who underwent surgical treatment from Jan 2009 to Dec 2016 were included. There were 323 patients in the TIVA group and 645 patients in the IHA group, with 1:2 PS matching. There was no significant difference in overall survival outcomes between the TIVA and IHA groups before matching the cohort (p = 0.566) or after matching the cohort (p = 0.679) by log-rank tests. In the Cox hazard regression model, there was no significant difference between the TIVA and IHA groups before (HR: 1.054, 95% CI: 0.881–1.262, p = 0.566) or after (HR: 0.957, 95% CI: 0.779–1.177, p = 0.679) PS matching. The meta-analysis of survival outcomes between the TIVA and IHA groups found critical statistical value in the before PS matching cohort (HR 0.74, 95% CI: 0.57–0.96 p < 0.01) and after PS matching cohort (HR: 0.65, 95% CI: 0.46–0.94, p < 0.01).

Conclusions

Combined with the results of previous studies, total intravenous anesthesia has been shown to be superior to inhalation anesthesia in terms of overall survival for gastric cancer patients undergoing surgical treatment. The selection of intravenous or inhalation anesthesia for gastric cancer surgery should take into account the long-term prognosis of the patient.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08946-7.

Impact of Type of Postoperative Complications on Long-Term Survival of Gastric Cancer Patients: Results From a High-Volume Institution in China

BACKGROUND

This study aimed to evaluate the impact of postoperative complication and its etiology on long-term survival for gastric cancer (GC) patients with curative resection.

METHODS

From January 2009 to December 2014, a total of 1,667 GC patients who had undergone curative gastrectomy were analyzed. Patients with severe complications (SCs) (Clavien-Dindo grade III or higher complications or those causing a hospital stay of 15 days or longer) were separated into a "complication group." Univariate and multivariate analyses were performed to reveal the relationship between postoperative complications and long-term survival. A 2:1 propensity score matching (PSM) was used to balance baseline parameters between the two groups.

RESULTS

SCs were diagnosed in 168 (10.08%) patients, including different etiology: infectious complications (ICs) in 111 (6.66%) and non-infectious complications (NICs) in 71 (4.26%) patients. Multivariate analysis showed that presence of SCs (P=0.001) was an independent prognostic factor for overall survival, and further analysis by complication type demonstrated that the deteriorated overall survival was mainly caused by ICs (P=0.004) rather than NICs (P=0.068). After PSM, patients with SCs (p=0.002) still had a significantly decreased overall survival, and the presence of ICs (P=0.002) rather than NICs (P=0.067) showed a negative impact on long-term survival.

CONCLUSION

Serious complications, particularly of an infectious type, may have a negative impact on overall survival of GC patients. However, additional multicenter prospective studies with larger sample size are required to verify this issue.

Safety and Efficacy of Laparoscopic Versus Open Gastrectomy in Patients With Advanced Gastric Cancer Following Neoadjuvant Chemotherapy: A Meta-Analysis

Background

Given the expanding clinical applications of laparoscopic surgery and neoadjuvant chemotherapy in advanced gastric cancer treatment, there is an emerging need to summarize the few evidences that evaluated the safety and efficacy of laparoscopic versus open gastrectomy in patients with advanced gastric cancer (AGC) following neoadjuvant chemotherapy (NAC).

Methods

From January 1 to 2, 2021, we searched Ovid Embase, PubMed, Cochrane central register Trials (Ovid), and web of science to find relevant studies published in English, and two authors independently performed literature screening, quality assessment of the included studies, data extraction, and data analysis. This study was registered with PROSPERO (CRD42021228845).

Results

The initial search retrieved 1567 articles, and 6 studies were finally included in the meta-analysis review, which comprised 2 randomized control trials and 4 observational studies involving 288 laparoscopic gastrectomy (LG) and 416 open gastrectomy (OG) AGC patients treated with NAC. For intraoperative conditions, R0 resection rate, blood transfusion, intraoperative blood loss, number of lymph nodes dissected, proximal margin, and distal margin were comparable between LG group and open OG group. For postoperative short-term clinical outcomes, LG has significantly less postoperative complications (OR = 0.65, 95%CI: 0.42-1.00, p = 0.05) and shorter postoperative time to first aerofluxus (WMD = -0.57d, 95%CI: -0.89-0.25, p = 0.0004) than OG, and anastomotic leakage, pulmonary infection, pleural effusion, surgical site infection, thrombosis, intestinal obstruction, peritoneal effusion or abscess formation, postoperative time to first defecation, postoperative time to first liquid diet, and postoperative length of stay were comparable between the two groups. For postoperative survival outcomes, there were no significant differences in disease-free survival (DFS) and overall survival (OS) between the two groups.

Conclusion

The available evidences indicated that LG is an effective and feasible technology for the treatment of AGC patients treated with NAC, and LG patients have much less postoperative complications and faster bowel function recovery than OG patients.

Systematic Review Registration

PROSPERO database (identifier, CRD42021228845).

Difference Between Signet Ring Cell Gastric Cancers and Non-Signet Ring Cell Gastric Cancers: A Systematic Review and Meta-Analysis

Background: There is controversy about the characteristics and prognostic implications of signet ring cell gastric cancers and non-signet ring cell gastric cancers.

Objective: This study aims to evaluate clinicopathological characteristics and prognoses of signet ring cell carcinoma (SRCC) and non-signet ring cell carcinoma (NSRCC) of stomach.

Methods: Studies compared between SRCC and NSRCC of the stomach after gastrectomy and published before September 1st, 2020, in the PubMed, Cochrane, and Embase databases, were identified systematically.

Results: A total of 2,865 studies were screened, and 36 studies were included, with 19,174 patients in the SRCC group and 55,942 patients in the NSRCC group. SRCC patients were younger in age (P < 0.001), less likely to be male patients (P < 0.001), more afflicted with upper third lesions (P < 0.001), and presenting with more Borrmann type IV tumors (P = 0.005) than NSRCC patients. Lymph nodes metastasis was similar between SRCC and NSRCC patients with advanced tumor stage (OR: 0.86, 95% CI: 0.671.10, P = 0.23), but lower in the SRCC than NSRCC patients with early tumor stage (OR: 0.73; 95% CI: 0.560.98, P = 0.02). SRCC patients had comparable survival outcomes with NSRCC patients for early gastric cancers (HR: 1.05, 95% CI: 0.651.68, P < 0.001) but had significantly poor prognosis for patients with advanced tumor stage (HR: 1.50, 95% CI: 1.281.76, P < 0.001).

Conclusions: Signet ring cell carcinomas of the stomach are an increasingly common histopathological subtype of gastric cancers. These kinds of patients tend to be younger in age and more often female. Although, signet ring cell gastric cancer is a negative prognostic factor for patients with advanced stage. The difference is that for early stage of signet ring cell gastric cancers, it has low lymph nodes metastasis rate and comparable prognosis with non-signet ring cell cancers.

Comparisons of perioperative and survival outcomes of laparoscopic versus open gastrectomy for serosa-positive (pT4a) gastric cancer patients: a propensity score matched analysis

BACKGROUND

Data about whether laparoscopic gastrectomy (LG) is applicable in serosa-positive (pT4a) gastric cancer patients remain rare. The purpose of this study is to compare the perioperative and long-term outcomes between the laparoscopic and open gastrectomy (OG) in pT4a gastric cancer patients who underwent curative resection.

METHODS

A total of 1086 consecutive pT4a patients (101 patients with LG and 985 with OG) who underwent curative gastrectomy in a high-volume center between 2006 and 2016 were evaluated. Demographics, surgical, and oncologic outcomes were analyzed. Propensity score matching (PSM) analysis was performed to balance baseline confounders, and COX regression analysis was performed to identify independent prognostic factors.

RESULTS

After PSM adjustment, a well-balanced cohort comprising 101 patients who underwent LG and 201 who underwent OG was analyzed. Operative time (288.7 vs. 234.2 min; P < 0.001) was significantly longer, while estimated blood loss (172.8 vs. 220.7 ml; P < 0.001) was significantly less in the LG group compared with the OG group. There were no significant differences between groups in total number of harvested lymph nodes, postoperative stays, readmission rate, and postoperative complication rate. The 3-year overall survival (OS) rate was not significant different in the LG and OG groups (66.7% vs. 62.8%, P = 0.668), and the subsequent multivariate analysis revealed that the surgical approach was not an independent prognostic factor for OS (HR = 1.123; 95%CI: 0.803-1.570; P = 0.499). In sensitivity analysis including 78 pairs well-matched patients operated by an experienced surgeon, the results were similar to these for the matched entire cohort.

CONCLUSION

LG can be a safe and feasible approach for pT4a gastric cancer treatment. However, well-designed high-quality RCTs are expected to draw a definitive conclusion on this topic.

Incidence of adhesive small bowel obstruction after gastrectomy for gastric cancer and its risk factors: a long-term retrospective cohort study from a high-volume institution in China

Adhesive small bowel obstruction (ASBO) has a significant impact on quality of life and medical costs. However, data about ASBO after gastrectomy remain sparse. From January 2009 to December 2017, 3025 patients who underwent gastrectomy for gastric cancer were retrospectively collected and analyzed. Clinicopathological materials were obtained retrospectively, and univariate and multivariate regression analyses were performed to determine risk factors for ASBO. A nomogram for the prediction of ASBO was generated using the results of multivariable analyses. Bootstraps with 1000 resamples were performed for internal validation. The performance of the model was assessed with its discrimination, calibration, and clinical usefulness. A total of 330 (10.9%) patients experienced at least one ASBO episode with a median follow-up of 57.0 (interquartile range 31.0-85.0) months. Logistic regression analysis showed that independent risk factors for ASBO were previous abdominal surgery (odds ratio, OR = 2.03), open gastrectomy (OR = 3.12), non-Billroth-1 reconstruction (Billroth-2, OR = 2.61; Roux-en-Y, OR = 1.99; esophagogastrostomy, OR = 2.79), D2/D2 + lymphadenectomy (OR = 2.64), combined organ resection (OR = 2.76), and postoperative intraabdominal complication (OR = 2.73). The nomogram showed good discrimination, with a C-index of 0.702 and good calibration. Decision curve analysis demonstrated that the nomogram was clinically useful. Several risk factors associated with ASBO after gastrectomy for gastric cancer were identified. Nomogram generated based on these factors could serve as a reliable tool to predict the probability of ASBO.

Indocyanine green fluorescence angiography prevents anastomotic leakage in rectal cancer surgery: a systematic review and meta-analysis

BACKGROUND

The role of intraoperative use of indocyanine green (ICG) fluorescence angiography (ICGFA) to prevent anastomotic leakage (AL) in rectal cancer surgery remains controversial.

METHODS

The systematic review for studies evaluating ICGFA in patients undergoing rectal cancer surgery in PubMed, Embase, Web of Science, and the Cochrane Library was performed up to April 30, 2020. The primary outcome was the incidence of AL. The analysis was performed using RevMan v5.3 and Stata v12.0 software.

RESULTS

Eighteen studies comprising 4038 patients were included. In the present meta-analysis, intraoperative use of ICGFA markedly reduced AL rate (OR = 0.33; 95% CI: 0.24-0.45; P < 0.0001; I² = 0%) in rectal cancer surgery, which was still significant in surgeries limited to symptomatic AL (OR = 0.44; 95% CI: 0.31-0.64; P < 0.0001; I² = 22%). This intervention was also associated with shorter postoperative stays (MD = - 1.27; 95% CI: - 2.42 to - 0.13; P = 0.04; I² = 60%). However, reoperation rate (OR = 0.61; 95% CI: 0.34-1.10; P = 0.10; I² = 6%), ileus rate (OR = 1.30; 95% CI: 0.60-2.82; P = 0.51; I² = 56%), and surgical site infection rate (OR = 1.40; 95% CI: 0.62-3.20; P = 0.42; I² = 0%) were not significantly different between the two groups.

CONCLUSION

The use of ICGFA was associated with a lower AL rate after rectal cancer resection. However, more multi-center RCTs with large sample size are required to further verify the value of ICGFA in rectal cancer surgery.

The Survival Benefit and Safety of Splenectomy for Gastric Cancer With Total Gastrectomy: Updated Results

Background

Splenectomy was traditionally performed to dissect the splenic hilar lymph nodes. Considering the important functions of spleen, whether splenectomy would bring beneficial to gastric cancer patients is debatable. This meta-analysis aimed to make an updated evaluation on the effectiveness and safety of splenectomy.

Methods

Literature searches were performed to identify eligible RCTs concerning effectiveness or safety of splenectomy with gastrectomy from PubMed, MEDLINE, CBMdisc, EMBASE, and Cochrane Central Register of Controlled Trials. Two reviewers completed the study selection, data extraction, and quality assessment independently. The meta-analyses were performed by RevMan 5.3.

Results

A total of 971 patients from four studies were included (485 in splenectomy group and 486 in spleen preservation group). Splenectomy did not increase 5-year overall survival rate (RR=1.05, 95% CI: 0.96, 1.16) or increase postoperative mortality (RR=1.21, 95% CI: 0.41, 3.54). However, the analysis demonstrated that gastrectomy with splenectomy had significantly higher incidence of postoperative complications (RR=1.80, 95% CI: 1.33, 2.45). No significant differences were found in terms of the number of resected lymph nodes and reoperation rate; however, splenectomy had a tendency to prolong the duration of surgery and hospital stays. Subgroup analyses indicated that splenectomy could not increase overall survival rate for either whole or proximal gastric cancer. Sensitivity analyses also found similar results compared to the primary analyses.

Conclusions

Splenectomy cannot benefit the survival of patients with tumor located at lesser curvature, and it could instead increase postoperative morbidity.

Reappraise role of No. 10 lymphadenectomy for proximal gastric cancer in the era of minimal invasive surgery during total gastrectomy: a pooled analysis of 4 prospective trial

BACKGROUND

For patients with locally advanced proximal gastric cancer (LAPGC), the individualized selection of patients with highly suspected splenic hilar (No. 10) lymph node (LN) metastasis to undergo splenic hilar lymphadenectomy, is a clinical dilemma. This study aimed to re-evaluate the feasibility and safety of laparoscopic spleen-preserving splenic hilar lymphadenectomy (LSPSHL) and to identify the population who would benefit from it.

METHODS

A total of 1068 patients (D2 group = 409; D2 + No. 10 group = 659) who underwent laparoscopic total gastrectomy from four prospective trials between January 2015 and July 2019 were analyzed.

RESULTS

No significant difference in the incidence (16.9% vs. 16.4%; P = 0.837) of postoperative complications were found between the two groups. The metastasis rate of No. 10 LN among patients in the D2 + No. 10 group was 10.3% (68/659). Based on the decision tree, patients with LAPGC with tumor invading the greater curvature (Gre), patients with non-Gre-invading LAPGC with a tumor size > 5 cm and clinical positive locoregional LNs were defined as the high-priority No. 10 dissection group. The metastasis rate of No. 10 LNs in the high-priority group was 19.4% (41/211). In high-priority group, the 3-year overall survival of the D2 + No. 10 group was better than that of the D2 group (74.4% vs. 42.1%; P = 0.005), and the therapeutic index of No. 10 was higher than the indices of most suprapancreatic stations.

CONCLUSIONS

LSPSHL for LAPGC is safe and feasible when performed by experienced surgeons. LSPSHL could be recommended for the high-priority group patients even without invasion of the Gre.

Closure of Petersen's defect in gastrectomy for gastric cancer: an interrupted time series analysis from a high-volume institution in China

PURPOSE

Petersen's hernia (PH) is a serious complication after gastrectomy for gastric cancer. The aim of this study was to investigate whether closure of Petersen's defect (PD) can decrease the rates of PH and suspected Petersen's hernia (SPH).

METHODS

Patients who underwent gastrectomy with PD were enrolled. From January 2014 to January 2017, we performed gastrectomy without PD closure (non-closure group). From February 2017 to June 2018, we closed PDs during gastrectomy (closure group). The rates of PH and SPH were compared between the two groups. The last follow-up was updated in August 2020.

RESULTS

Among a total of 1213 patients, 12 patients (1.0%) developed PH, and 23 patients (1.9%) developed SPH. The rate of PH in the closure group was significantly lower than that in the non-closure group (1/385, 0.3% versus 11/828, 1.3%, p = 0.042, log-rank test). The rate of SPH in the closure group was significantly lower than that in the non-closure group (1/385, 0.3% versus 22/828, 2.7%, p = 0.008, log-rank test). Non-closure of PD was a risk factor for PH and SPH (odds ratio (OR) 7.72, 95% CI 1.84-32.35, p = 0.006).

CONCLUSIONS

PD closure is recommended after gastrectomy for gastric cancer, as the rates of PH and SPH were significantly decreased.

Application of clockwise modularized laparoscopic lymphadenectomy in the suprapancreatic area, a propensity score matching study and comparison with open gastrectomy

BACKGROUND

Suprapancreatic lymphadenectomy is the essence of D2 radical gastric cancer surgery. The present study aimed to describe clockwise modularized laparoscopic lymphadenectomy in the suprapancreatic area.

METHODS

The data from gastric cancer patients who underwent surgical treatment from September 2016 to December 2018 were collected. Patients were divided into clockwise modularized lymphadenectomy (CML) and traditional open gastrectomy (OG) groups according to the surgical treatment strategy. The propensity score matching method was utilized to balance the baseline characteristics between the two groups.

RESULTS

Finally, 551 gastric cancer patients were included in the present study. Following propensity score matching, 106 pairs of patients in the CML group and OG group were included in the final analysis. The CML group had more total examined lymph nodes (36, IQR 28-44.74 vs. 29, IQR 29-39.5, p = 0.002) and no. 9 station nodes (2, IQR 1-5 vs. 2, IQR 1-3, p = 0.007) than the OG group. There was less intraoperative blood loss (30, IQR 20-80 ml vs. 80, IQR 50-80 ml, p < 0.001) and a longer surgical duration (262.5 min, IQR 220-303.25 min vs. 232, IQR 220-255 min, p < 0.001) in the CML group than in the OG group. The incidence of postoperative complications (19.8% vs. 16.0%, p = 0.591) and postoperative hospital stay (8, IQR 7-9 days vs. 8, IQR 7-9 days, p = 0.452) were comparable between the CML and OG groups.

CONCLUSION

Laparoscopic lymphadenectomy for gastric cancer surgery is technically demanding. Clockwise modularized laparoscopic lymphadenectomy in the suprapancreatic area can attain similar effects as traditional open surgery and without an increase in postoperative adverse events.

The value of spleen-preserving lymphadenectomy in total gastrectomy for gastric and esophagogastric junctional adenocarcinomas: A long-term retrospective propensity score match study from a high-volume institution in China

BACKGROUND

The benefit of removing the splenic lymph nodes in patients with proximal gastric cancer has been controversial. The purpose of our study was to investigate the importance of performing a splenic hilar lymph node dissection without splenectomy in patients undergoing total gastrectomy for gastric cancer.

METHODS

From January 2006 to December 2015, we retrospectively reviewed patients who underwent a curative total gastrectomy for gastric cancer. Propensity score matching was used to balance any potential discrepancy of the other covariates between patients with and without splenic hilar lymph node dissection. Survival analysis, Cox univariate and multivariate analysis, and subgroups analysis were conducted to determine the value of splenic hilar lymph node dissection. After matching, 2 nomograms among patients with and without splenic hilar lymph node dissection were established respectively, the C-index, calibration curve and decision curve analysis were used to further evaluate the value of splenic hilar lymph node dissection.

RESULTS

The rate of metastatic splenic hilar lymph nodes in the 274 patients undergoing splenic hilar lymph node dissection was 16.4% (45/274). Patients undergoing splenic hilar lymph node dissection had better survival outcomes than those not undergoing splenic hilar lymph node dissection before (P = .003) and after (P = .003) propensity score matching. Cox multivariate analysis also confirmed that splenic hilar lymph node dissection was an independent prognostic factor both before (hazard ratio 1.284, 95% confidence interval 1.042-1.583, P = .019) and after (hazard ratio 1.480, 95% confidence interval 1.156-1.894, P = .002) propensity score matching. Subgroup analysis indicted that splenic hilar lymph node dissection offered better survival outcomes for esophagogastric junctional adenocarcinoma (P < .001, P for interaction = .018). After propensity score matching, the nomogram of patients with splenic hilar lymph node dissection (C-index 0.735, 95% confidence interval 0.695-0.774) also indicated a statistically significant advantage compared with that without splenic hilar lymph node dissection (C-index 0.708, 95% confidence interval 0.668-0.748, P < .001).

CONCLUSION

Our study suggests that spleen-preserving splenic hilar lymph node dissection should be an essential procedure among patients undergoing total gastrectomy.

The Significance of the CLDN18-ARHGAP Fusion Gene in Gastric Cancer: A Systematic Review and Meta-Analysis

Objective: The objective of this study was to summarize the clinicopathological characteristics of the CLDN18-ARHGAP fusion gene in gastric cancer patients.

Background: The CLDN18-ARHGAP26 fusion gene is one of the most frequent somatic genomic rearrangements in gastric cancer, especially in the genomically stable (GS) subtype. However, the clinical and prognostic meaning of the CLDN18-ARHGAP fusion in gastric cancer patients is unclear.

Methods: Studies that investigated CLDN18-ARHGAP fusion gastric cancer patients were identified systematically from the PubMed, Cochrane, and Embase databases through the 28th of February 2020. A systematic review and meta-analysis were performed to estimate the clinical significance of CLDN18-ARHGAP fusion in patients.

Results: A total of five eligible studies covering 1908 patients were selected for inclusion in the meta-analysis based on specified inclusion and exclusion criteria. Several fusion patterns were observed linking CLDN18 and ARHGAP26 or ARHGAP6, with the most common type being CLDN18/exon5-ARHGAP26/exon12. The survival outcome meta-analysis of the CLDN18-ARHGAP fusion gene showed that it was associated with overall survival outcomes in gastric cancer (HR, 2.03, 95% CI 1.26–3.26, P < 0.01, random-effects). In addition, diffuse gastric cancer had a greater proportion of CLDN18-ARHGAP fusions than intestinal gastric cancer (13.3%, 151/1,138 vs. 1.8%, 8/442; p < 0.001). Moreover, gastric cancer patients with the CLDN18-ARHGAP fusion gene are more likely to be female or have a younger age, lymph node metastasis and advanced TNM stages.

Conclusion: The CLDN18-ARHGAP fusion is one of the molecular characteristics of diffuse gastric cancer and is also an independent prognostic risk factor for gastric cancer. In addition, it is also related to multiple clinical characteristics, including age, sex, lymph node metastasis and tumor stage. However, the mechanism of the CLDN18-ARHGAP fusion gene and potential targeted therapeutic strategies need further exploration.

The Role of HER2 in Self-Renewal, Invasion, and Tumorigenicity of Gastric Cancer Stem Cells

Background

Deregulation of HER2 expression could affect the biological characteristics of gastric cancer cells and treatment option for gastric cancer patients. This research aims to investigate the impact of HER2 on biological characteristics of gastric cancer stem cells (GCSCs) and prognosis of gastric cancer patients.

Methods

HER2 knockdown in GCSCs were constructed by lentivirus transfection. Alterations of proliferation, self-renewal, invasion, migration, colony formation, and tumorigenicity of GCSCs were examined. The changes of gene expressions after HER2 interference in GCSCs were detected by gene microarray. The impact of concentration of serum HER2 and expression of HER2 in tumor tissues on survival of 213 gastric cancer patients was also analyzed.

Results

Down-regulation of HER2 decreased the self-renewal, colony formation, migration, invasion, proliferation, and chemotherapy resistance of GCSCs. However, the tumorigenicity of GCSCs in vivo was increased after down-regulation of HER2. The results of gene microarray showed that HER2 gene might regulate the signal transduction of mTOR, Jak-STAT, and other signal pathways and affect the biological characteristics of GCSCs. Furthermore, survival analyses indicated that patients with high concentration of HER2 in serum had a favorable overall survival. However, there was no significant correlation between expression of HER2 in tumor tissue and overall survival.

Conclusion

Interference of HER2 in GCSCs decreased the capacity of self-renewal, proliferation, colony formation, chemotherapy resistance, invasion, and migration but might increase the tumorigenicity in vivo. Patients with high concentration of HER2 in serum seemed to have a favorable prognosis.

Prognostic Value of Changes in Preoperative and Postoperative Serum CA19-9 Levels in Gastric Cancer

Objective: The prognostic significance of serum CA19-9 levels in gastric cancer patients remains a matter debate. The aim of this study was to determine the prognostic value of changes in preoperative and postoperative serum CA19-9 levels in patients with gastric cancer.

Methods: A total of 1,046 gastric cancer patients who underwent curative gastrectomy in West China Hospital of Sichuan University from January 2011 to December 2016 were analyzed retrospectively. Patients were categorized by minimum P-value using X-tile, while the baseline confounders for CA19-9 changes were balanced through propensity score matching (PSM). The relationships between CA19-9 changes and other clinicopathologic features were measured. Univariate and multivariate analysis were performed to explore the risk factors associated with survival outcomes.

Results: We included 653 patients. Changes in CA19-9 levels significantly correlated with age, tumor size, macroscopic type, histological grade, T stage and TNM stage. Kaplan–Meier curves revealed that patients with CA19-9 changes <20% had significant better overall survival than those with changes more than 20% (p < 0.001); Cox regression analysis revealed the CA19-9 change (p = 0.010), gender (p = 0.031), histological grade (p = 0.036) and TNM stage (p < 0.001) were independent risk factors for survival after PSM. Stratification analysis indicated that patients with CA19-9 change more than 20% had worse prognosis that those with CA19-9 change no more than 20% in male (p = 0.002), poorly differentiated or undifferentiated type (p = 0.031) and TNM stage III (p = 0.006).

Conclusion: Changes in preoperative and postoperative serum CA19-9 levels were closely associated with clinicopathological traits and was an independent prognostic factor in gastric cancer patients. This parameter may be a reliable marker for prediction of survival.

Prognostic impact of Borrmann classification on advanced gastric cancer: a retrospective cohort from a single institution in western China

Background

Due to the controversy over the prognostic significance of Borrmann type in patients with gastric cancer (GC), the present study was to investigate the clinical value of Borrmann type in advanced GC.

Methods

We retrospectively evaluated 2092 patients with advanced GC and subsequently examined the clinicopathological characteristics and prognosis of patients stratified by Borrmann type.

Results

Patients were divided into three groups according to Borrmann type (Borrmann types I+II, III, and IV). Patients with Borrmann types III and IV had larger size, more poorly differentiated tumor type, more advanced tumor stage, and higher chance of involving the entire stomach. The overall survival (OS) rates were significantly different among the three groups (p < 0.001). Stratification analysis revealed significant OS rates among the three groups in tumor-node-metastasis (TNM) stage III (p < 0.001) and TNM stage IV (p = 0.008). Multivariate analysis revealed that Borrmann types, adjuvant chemotherapy, curative resection, and TNM stage were all independent predictors of OS among GC patients. The subgroup analysis indicated that Borrmann type was an independent predictor of OS among GC patients who undergone curative resection and with TNM stage III cancer. However, curative resection and postoperative chemotherapy failed to prolong the survival of patients with Borrmann type IV.

Conclusions

The clinicopathological characteristics and prognosis of patients with three Borrmann types of GC were different. Borrmann type can be simply used as a valuable factor to predict survival in advanced GC patients, especially in those TNM stage III undergoing curative resection. Additionally, more attention should be paid to the treatment for Borrmann type IV GC.

Development and validation of a nomogram for predicting overall survival of gastric cancer patients after D2R0 resection

OBJECTIVE

The aim of the study was to find factors associated with overall survival (OS) and establish a nomogram predicting OS of patients with gastric cancer (GC) after D2R0 resection.

METHODS

Demographic and clinicopathologic factors of patients with GC underwent D2R0 surgical resection were retrospectively collected from medical records, telephone interview or outpatient follow-up. To find factors significantly associated with OS, univariate and multivariate analyses were conducted. The concordance index (C-index) was used to measure the accuracy of the nomogram. Discrimination and calibration of the nomogram were tested using the patients in the validation set.

RESULTS

Overall, patients with 890 GC underwent D2R0 surgical resection were included. Based on the results of univariate analysis and multivariate analysis, T stage, number of metastatic local lymph nodes, lymph node positive rate, adjuvant chemotherapy and diameter of tumour were used to construct a nomogram predicting OS of patients with GC after surgical resection. In the validation cohort, the C-index was 0.73 and the nomogram performed well in predicting OS.

CONCLUSION

The nomogram was able to accurately predict OS of patients with GC underwent curative surgery and performed well in internal validation, which would also be useful for the decision-making of doctors.

Visceral Fat Area (VFA) Superior to BMI for Predicting Postoperative Complications After Radical Gastrectomy: a Prospective Cohort Study

BACKGROUND

Obesity may impact surgical outcomes of gastrectomy. Whether visceral fat area (VFA) is a better obesity parameter than body mass index (BMI) is still controversial. The aim of this study is to compare the accuracy and effectiveness of VFA and BMI in predicting the short-term surgical outcomes of gastrectomy.

METHODS

Patients who were diagnosed with gastric cancer were measured for BMI and VFA preoperatively and then divided into a VFA-H (VFA-high) group and VFA-L (VFA-low) group, at the cutoff point of 100 cm², and a BMI-H (BMI-high) group and BMI-L (BMI-low) group, at the cutoff point of 25 kg/m². The short-term surgical outcomes were compared between the different groups.

RESULTS

In total, 276 patients were enrolled in this study; 55 (19.9%) patients were classified into the BMI-H group, and 122 (44.2%) patients were classified into the VFA-H group. There was a significant correlation between BMI and VFA (r = 0.652, p < 0.001). Compared with the VFA-L group, the VFA-H group had a higher incidence of postoperative complications (31.1% vs. 13.0%; p < 0.001), longer operation duration (270.0 (235.0-305.0) vs. 255.0 (223.8-295.0), p = 0.046), and more blood loss (100.0 (100.0-150.0) vs. 80.0 (80.0-100.0), p < 0.001), while the BMI-H group had more blood loss than the BMI-L group (100.0 (100.0-120.0) vs. 100.0(80.0-100.0), p = 0.006). Logistic regression showed that VFA was an independent risk factor for postoperative complications (odds ratio 2.813, 95% CI 1.523-5.194; p = 0.001).

CONCLUSION

For gastric cancer patients, VFA is superior to BMI in accurately and effectively illuminating the impact of obesity on short-term surgical outcomes.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT02800005.

[Effect of standardized surgical treatment and multidisciplinary treatment strategy on the prognosis of gastric cancer patients: report of a single-center cohort study]

Objective: To explore the effect of standardized surgical treatment and multidisciplinary treatment strategy on the treatment outcomes of gastric cancer patients. Methods: A single-center cohort study was carried out. Clinicopathological and long-term follow up data of primary gastric cancer patients were retrieved from the database of Surgical Gastric Cancer Patient Registry (SGCPR) in West China Hospital of Sichuan University. Finally, 4516 gastric cancer patients were included and were divided into three groups according to time periods (period 1 group: exploration stage of standardized surgical treatment, 2000 to 2006, 967 cases; period 2 group: application stage of standardized surgical treatment, 2007 to 2012, 1962 cases; period 3 group: optimization stage of standardized surgical treatment and application stage of multidisciplinary treatment strategy, 2013 to 2016, 1587 cases). Differences in clinical data, pathologic features, and prognosis were compared among 3 period groups. Follow-up information was updated to January 1, 2020. The overall follow-up rate was 88.9% (4016/4516) and median follow-up duration was 51.58 months. Survival curve was drawn by Kaplan-Meire method and compared with log-rank test. Univariate and multivariate analyses were performed by Cox proportional hazards model. Results: There were significant differences among period 1, period 2 and period 3 groups in the rates of D2/D2+ lymphadenectomy [14.4%(139/967) vs. 47.2%(927/1962) vs. 75.4%(1197/1587), χ(2)=907.210, P<0.001], in the ratio of proximal gastrectomy [19.8%(191/967) vs. 16.6%(325/1962) vs. 8.2%(130/1587), χ(2)=100.020, P<0.001], and in the median intraoperative blood loss (300 ml vs. 100 ml vs. 100 ml, H=1126.500, P<0.001). Besides, the increasing trend and significant difference were also observed in the median number of examined lymph nodes among period 1, period 2 and period 3 groups (14 vs. 26 vs. 30, H=987.100, P<0.001). Survival analysis showed that the 5-year overall survival rate was 55.3% in period 1, 55.2% in period 2 and 62.8% in period 3, and significant difference existed between period 3 and period 1 (P=0.004). The Cox proportional hazards model analysis showed that treatment period (period 3, HR=0.820, 95%CI: 0.708 to 0.950, P=0.008), postoperative chemotherapy (HR=0.696, 95%CI: 0.631 to 0.768, P<0.001) and mid-low gastric cancer (HR=0.884, 95%CI: 0.804 to 0.973, P=0.011) were good prognostic factors. Whereas old age (≥65 years, HR=1.189, 95%CI: 1.084 to 1.303, P<0.001), palliative resection (R1/R2, HR=1.538,95%CI: 1.333 to 1.776, P<0.001), large tumor size (≥5 cm, HR=1.377, 95%CI: 1.239 to 1.529, P<0.001), macroscopic type III to IV (HR=1.165, 95%CI: 1.063 to 1.277, P<0.001) and TNM stage II to IV(II/I:HR=1.801,95%CI:1.500~2.162,P<0.001;III/I:HR=3.588, 95%CI: 3.028~4.251, P<0.001; IV/I: HR=6.114, 95%CI: 4.973~7.516, P<0.001) were independent prognostic risk factors. Conclusion: Through the implementation of standardized surgical treatment technology and multidisciplinary treatment model, the quality of surgery treatment and overall survival increase, and prognosis of gastric cancer patients has been improved.

Prevalence difference of Helicobacter pylori infection between Tibetan and Han ethnics: The protocol of a meta-analysis on epidemiologic studies

OBJECTIVES

Helicobacter pylori (Hp) is an identified carcinogenic pathogen of human gastric cancer. China is not only one of the countries with high incidence and mortality of gastric cancer, but also a high infection area of Hp. As a multi-ethnic country, China may have a diverse prevalence of Hp infection among ethnics. This meta-analysis tends to compare the prevalence of Hp infection between Tibetan and Han ethnics, the results may provide evidence for targeted screening and eradication of Hp in China.

METHODS

The following databases will be searched: PubMed, Web of Science, Technology Periodical Database (VIP), China National Knowledge infrastructure (CNKI), and WanFang databases. Studies which reported the prevalence of Hp infection between Tibetans and Hans in China are eligible. Two reviewers will independently screen studies, extract data and assess the risk of bias of included studies. The prevalence of Hp infection between Tibetan and Han ethnics will be compared by meta-analysis. Heterogeneity tests and meta-analyses will be conducted using RevMan 5.3 and Stata 12.0 softwares. Meanwhile, subgroup analysis, publication bias and sensitivity analysis evaluation will be performed where applicable.

RESULTS

This study will be reported in compliance with the PRISMA statement.This systematic review will not be submitted for any ethical approval since no privacy health information will be included. The findings will be published through peer-reviewed publications or conference presentations.

PROSPERO REGISTRATION NUMBER

CRD42019121192.

CONCLUSIONS

Our study will provide us evidence for tailored strategy and robustness of Hp screening and eradication among Tibetans.

Electronic and transport properties and physical field coupling effects for net-Y nanoribbons

Recently, a new type of quasi-1D graphene-like nanoribbons, periodically embedded with four- and eight- membered rings, has been successfully fabricated, and based on this structure, a novel planar 2D carbon allotrope, the so-called the net-Y, has been proposed. Here, we study various nanoribbons derived from such a 2D monolayer focusing on the structure stability, electronic, and transport properties, especially on the physical field coupling effects of electronic behaviors. Very high stability is predicted for various types of nanoribbons by the calculated binding energy and molecular dynamics simulation. Different edge shapes and widths have a significant influence on their electronic properties. Armchair nanoribbons are always semiconductors, and possess a high carrier mobility. After hydrogen termination, some metallic nanoribbons can become semiconductors or quasi-metals with massless Dirac-fermion behavior. In particular, the electronic properties of ribbons can be effectively modulated by applying strain and electric field. The band gap size and the transition from indirect to direct band gap can be realized upon strain or electric field. These flexibly tunable electronic properties for nanoribbons expand their applications in nanoelectronics and optoelectronics.

[Comparison of safety and efficacy between proximal gastrectomy and total gastrectomy for upper third gastric cancer: a Meta-analysis]

Objective: To compare the safety and efficacy between proximal gastrectomy and total gastrectomy and to ascertain the optimized procedure for patients with upper third gastric cancer through meta-analysis. Methods: The English literatures about proximal gastrectomy and total gastrectomy for upper third gastric cancer were searched from PubMed, EMBASE, the Cochrane Library and the Web of Science database and then collected. The quality of enrolled studies was independently assessed by two researchers according to the Newcastle-Ottawa Scale for retrospective studies and Jadad scale for RCT studies. The basic information of the literature and related clinical indicators were extracted. The primary endpoints were 5-year overall survival rate and recurrence rate. The secondary endpoints were operative time, intraoperative blood loss, morbidity of postoperative complication, incidence of anastomotic stenosis and incidence of reflux esophagitis. Considering the influence of tumor staging on postoperative clinicopathological features and prognosis, a subgroup analysis was performed on the literatures including cases of early gastric cancer and those including cases of tumor stage I to IV. Statistical analyses were carried out by the "metafor" and "meta" software packages from RevMan 5.3 software and R software (V3.2.4). Results: Twenty-five literatures involving 3667 patients (proximal gastrectomy for 1483, total gastrectomy for 2184) were finally enrolled for analysis, including 24 retrospective studies with ≥ 5 points and 1 RCT with 3 points, and all the literatures were of high quality. A total of 2516 cases of early gastric cancer were enrolled in 18 articles, including 1027 with proximal gastrectomy and 1489 with total gastrectomy. A total of 1151 cases with stage I to IV were enrolled in 7 articles, including 456 in proximal gastrectomy group and 695 in total gastrectomy group. Five-year survival rate was not significantly different for patients with early gastric cancer between the proximal gastrectomy group and total gastrectomy group (OR=1.16, 95% CI: 0.72 to 1.86, P=0.54). Similarly, there was no significant difference for patients with stage I to IV between the proximal gastrectomy group and the total gastrectomy group (OR=1.19, 95% CI: 0.92 to 1.53, P=0.18). Recurrence rate of early gastric cancer patients was not significantly different between the proximal gastrectomy group and the total gastrectomy group (OR=0.40, 95% CI: 0.05 to 3.16, P=0.39).However, the recurrence rate of the proximal gastrectomy group was higher than that of the total gastrectomy group in patients with stage I to IV (OR=1.55, 95% CI: 1.09 to 2.19, P<0.01), whose difference was statistically significant. There was no significant differences in postoperative complication between the groups, both in patients with early gastric cancer, and in those with stage I to IV (both P>0.05). The incidences of postoperative anastomotic stenosis (OR=3.57, 95% CI: 1.82 to 6.99, P<0.01) and reflux esophagitis (OR=2.83, 95% CI: 1.23 to 6.54, P=0.01) in the proximal gastrectomy group were significantly higher than those in the total gastrectomy group in patients with early gastric cancer. Conclusions: There is no significant difference in long-term survival outcomes between total gastrectomy and proximal gastrectomy for upper gastric tumors. However,incidence of anastomotic stenosis and reflux esophagitis, and tumor recurrence rate after total gastrectomy are significantly lower. The total gastrectomy is recommended as the first choice for advanced upper gastric tumor.

[Infrapyloric lymph node dissection in gastric cancer radical surgery under the guidance of mesenteric anatomy theory]

The most common metastasis modality of gastric cancer is the perigastric lymph node metastasis. Complete dissection of regional lymph nodes of the stomach is the core surgical treatment strategy of gastric cancer, and is closely related to the prognosis of gastric cancer patients. Infrapyloric lymph node metastasis is common in gastric cancer,and its incomplete dissection is associated with tumor recurrence. Meanwhile, anatomical variations of vessels and complex mesentery layers of infrapyloric area increase the difficulty of lymphadenectomy during the operation. So, infrapyloric lymph node (No. 6) is an important station. Based on the theory of embryonic development and complete mesogastrium excision, operation across the anatomical space among mesentery layers can ensure en bloc resection of the infrapyloric lymph nodes.

"Four-Step Procedure" of laparoscopic exploration for gastric cancer in West China Hospital: a retrospective observational analysis from a high-volume institution in China

BACKGROUND

The preoperative work-up has limitations on finding peritoneal dissemination (PD) in gastric cancer patients. Laparoscopic exploration (LE) can discover radiographically occult PD, obtain accurate stage and avert futile laparotomy. The aim of our study was to introduce "Four-Step Procedure" LE in West China Hospital and further evaluate its safety and feasibility.

METHODS

We conducted a retrospective analysis on 165 patients from July 2016 to December 2017 who underwent "Four-Step Procedure" LE in gastrointestinal surgery department of West China Hospital. All the patients were diagnosed with gastric adenocarcinoma without explicit distant metastasis through Computed Tomography and/or Gastrointestinal Ultrasonography. Peritoneal lavage cytological examination (CY) was routinely performed during LE in our research. The "Four-Step" technical process of LE was introduced comprehensively. The clinicopathologic features and the presence of PD or CY at LE were analyzed, and the stratified analysis by cT and cN stages on the proportion of P1 and/or CY1 was also reported in this study.

RESULTS

Total of 165 patients accepted LE in our study, among these patients: 27 (16.4%) patients with P1 and/or CY1: 19 (11.5%) patients were found PD (P1), 17 (10.3%) patients with positive cytological examination (CY1) and 9 (3.6%) patients with P1Cy1. The stratified analysis by cT stage indicated that there was no P1 and/or Cy1 in cT1-cT2 stages, 1 (2.7%) patient with P1 and 1 (2.7%) with Cy1 in cT3 stage, 18 (20.0%) patients with P1 and 16 (17.8%) with Cy1 in cT4 stage. After LE, there were 74 (44.8%) patients underwent laparoscopic assistant gastrectomy, 25 (15.2%) patients with open gastrectomy, 50 (30.3%) patients with neoadjuvant chemotherapy and 16 (9.7%) patients with palliative chemotherapy and/or conversion therapy.

CONCLUSION

"Four-Step Procedure" LE is reliable and feasible for gastric cancer. From our study, LE has unique superiority on ascertaining PD and cytological examination and LE should be recommended in cT4 stage gastric cancer before resection.

[Efficacy and outcome of transcatheter closure of patent foramen ovale in patients with cryptogenic stroke]

Objective: To investigate the efficacy and outcome of transcatheter patent foramen ovale (PFO) closure in patients with cryptogenic stroke (CS). Methods: Sixty consecutive patients with cryptogenic stroke who undertook transcatheter PFO closure between May 2015 and September 2017 in Beijing Tiantan Hospital were enrolled in this prospective study.Transcranial Doppler (TCD) bubble test was performed and right-left shunt(RLS) was confirmed in all patients.Closure success rate,effective closure rate, complications, recurrence of ischemic stroke and new onset atrial fibrillation were evaluated. Results: A total of 60 patients (42 male,age range 24-68 (47±11)years) were included in the study.PFO size (motionless state) was (1.6±0.6)mm.RLS before closure was graded and 11 patients had moderate RLS and 48 patients had large RLS (include 41 patients who experienced shower or curtain effect).Closure success rate was 100% (60/60).No severe complications were observed.At 6 months,45 patients completed TCD bubble test.Of these, 4 patients suffered from moderate to large residual and thus effective closure rate was 91%(41/45).The mean follow-up period was 2-29 (median 12) months. During the follow-up, only 1 patient experienced recurrent cerebral infarction.New onset atrial fibrillation was not detected. Conclusion: Transcatheter PFO closure is effective,safe and related with a good outcome in reduction of recurrent CS for patients with PFO.