Machine learning identifies the risk of complications after laparoscopic radical gastrectomy for gastric cancer

BACKGROUND Laparoscopic radical gastrectomy is widely used,and perioperative complications have become a highly concerned issue.AIM To develop a predictive model for complications in laparoscopic radical gastrectomy for gastric cancer to better predict the likelihood of complications in gastric cancer patients within 30 days after surgery,guide perioperative treatment strategies for gastric cancer patients,and prevent serious complications.METHODS In total,998 patients who underwent laparoscopic radical gastrectomy for gastric cancer at 16 Chinese medical centers were included in the training group for the complication model,and 398 patients were included in the validation group.The clinicopathological data and 30-d postoperative complications of gastric cancer patients were collected.Three machine learning methods,lasso regression,random forest,and artificial neural networks,were used to construct postoperative complication prediction models for laparoscopic distal gastrectomy and laparoscopic total gastrectomy,and their prediction efficacy and accuracy were evaluated.RESULTS The constructed complication model,particularly the random forest model,could better predict serious complications in gastric cancer patients undergoing laparoscopic radical gastrectomy.It exhibited stable performance in external validation and is worthy of further promotion in more centers.CONCLUSION Using the risk factors identified in multicenter datasets,highly sensitive risk prediction models for complications following laparoscopic radical gastrectomy were established.We hope to facilitate the diagnosis and treatment of preoperative and postoperative decision-making by using these models.

Optimal choice of stapler and digestive tract reconstruction method after distal gastrectomy for gastric cancer:A prospective case–control study

BACKGROUND Gastric cancer is the most common cause of cancer-related deaths,and is classified according to its location in the proximal,middle,or distal stomach.Surgical resection is the primary approach for treating gastric cancer.This prospective study aimed to determine the best reconstruction method after distal gastrectomy for gastric cancer.AIM To explore the efficacy of different staplers and digestive tract reconstruction(DTR)methods after radical gastrectomy and their influence on prognosis.METHODS Eighty-seven patients who underwent radical gastrectomy for distal gastric cancer at our institution between April 2017 and April 2020 were included in this study,with a follow-up period of 12-26 mo.The patients were assigned to four groups based on the stapler and DTR plan as follows:BillrothⅠ(B-I)reconstruction+linear stapler group(group A,22 cases),B-I reconstruction+circular stapler group(group B,22 cases),Billroth II(B-II)reconstruction+linear stapler group(group C,22 cases),and B-II reconstruction+circular stapler group(group D,21 cases).The pathological parameters,postoperative gastrointestinal function recovery,postoperative complications,and quality of life(QOL)were compared among the four groups.RESULTS No significant differences in the maximum diameter of the gastric tumors,total number of lymph nodes dissected,drainage tube removal time,QLQ(QOL questionnaire)-C30 and QLQ-STO22 scores at 1 year postoperatively,and incidence of complications were observed among the four groups(P>0.05).However,groups A and C(linear stapler)had significantly lower intraoperative blood loss and significantly shorter anastomosis time,operation time,first fluid diet intake time,first exhaust time,and length of postoperative hospital stay(P<0.05)than groups B and D(circular stapler).CONCLUSION Linear staplers offer several advantages for postoperative recovery.B-I and B-II reconstruction methods had similar effects on QOL.The optimal solution can be selected according to individual conditions and postoperative convenience.

Utilization of deep neuromuscular blockade combined with reduced abdominal pressure in laparoscopic radical gastrectomy for gastric cancer:An academic perspective

BACKGROUND Few studies have examined the specific efficacy of deep neuromuscular blockade(NMB)combined with pneumoperitoneal pressure reduction in laparoscopic radical gastrectomy(LRG)in the elderly.AIM To investigate the application effect of deep neuromuscular blockade(NMB)combined with reduced pneumoperitoneum pressure in LRG for gastric cancer(GC)in elderly patients and its influence on inflammation.METHODS Totally 103 elderly patients with GC treated in our hospital between January 2020 and January 2022 were retrospectively analyzed.Among them,45 patients treated with surgery based on deep NMB and conventional pneumoperitoneum pressure were assigned to the control group,while the rest of the 58 patients who underwent surgery based on deep NMB and reduced pneumoperitoneum pressure were assigned to the observation group.The two groups were compared in the changes of the Leiden-surgical rating scale score,serum tumor necrosis fact-α(TNF-α)and interleukin 6(IL-6)before and after therapy.The visual analogue scale(VAS)was adopted for evaluating the shoulder pain of patients at 8 h,24 h and 48 h after the operation.The driving pressure of the two groups at different time points was also compared.Additionally,the operation time,pneumoperitoneum time,infusion volume,blood loss,extubation time after surgery,residence time in the resuscitation room,TOF%=90%time and post-anesthetic recovery room(PACU)stay time were all recorded,and adverse PACU-associated respiratory events were also recorded.The postoperative hospitalization time and postoperative expenses of the two groups were counted and compared.RESULTS No significant difference was found between the two groups at the time of skin incision,60 minutes since the operation and abdominal closure after surgery(P>0.05).The observation group exhibited significantly lower VAS scores than the control group at 24 and 48h after surgery(P<0.05).Additionally,the observation group had significantly lower driving pressure than the control group at 5 min and 60 min after the establishment of pneumoperitoneum(P<0.05).Additionally,the two groups were similar in terms of the operation time,pneumoperitoneum time,infusion volume,blood loss,extubation time after surgery,residence time in the resuscitation room and TOF%=90%time(P>0.05),and the observation group showed significantly lower TNF-αand IL-6 Levels than the control group at 24 h after therapy(P<0.05).Moreover,the incidence of adverse events was not significantly different between the two groups(P>0.05),and the observation group experienced significantly less hospitalization time and postoperative expenses than the control group(P<0.05).CONCLUSION Deep NMB combined with reduced pneumoperitoneum pressure can decrease the VAS score of shoulder pain and inflammatory reaction,without hindering the surgical vision and increasing adverse PACU-associated respiratory events,and can thus shorten the hospitalization time and treatment cost for patient.

Prognostic value and nomograms of proximal margin distance in gastric cancer with radical distal gastrectomy

Objective:The proximal margin(PM)distance for distal gastrectomy(DG)of gastric cancer(GC)remains controversial.This study investigated the prognostic value of PM distance for survival outcomes,and aimed to combine clinicopathologic variables associated with survival outcomes after DG with different PM distance for GC into a prediction nomogram.Methods:Patients who underwent radical DG from June 2004 to June 2014 at Department of General Surgery,Nanfang Hospital,Southern Medical University were included.The first endpoints of the prognostic value of PM distance(assessed in 0.5 cm increments)for disease-free survival(DFS)and overall survival(OS)were assessed.Multivariate analysis by Cox proportional hazards regression was performed using the training set,and the nomogram was constructed,patients were chronologically assigned to the training set for dates from June 1,2004 to January 30,2012(n=493)and to the validation set from February 1,2012 to June 30,2014(n=211).Results:Among 704 patients with p TNM stage I,p TNM stage II,T1-2,T3-4,N0,differentiated type,tumor size≤5.0 cm,a PM of(2.1-5.0)cm vs.PM≤2.0 cm showed a statistically significant difference in DFS and OS,while a PM>5.0 cm was not associated with any further improvement in DFS and OS vs.a PM of 2.1-5.0 cm.In patients with p TNM stage III,N1,N2-3,undifferentiated type,tumor size>5.0 cm,the PM distance was not significantly correlated with DFS and OS between patients with a PM of(2.1-5.0)cm and a PM≤2 cm,or between patients with a PM>5.0 cm and a PM of(2.1-5.0)cm,so there were no significant differences across the three PM groups.In the training set,the C-indexes of DFS and OS,were 0.721 and 0.735,respectively,and in the validation set,the C-indexes of DFS and OS,were 0.752 and 0.751,respectively.Conclusions:It is necessary to obtain not less than 2.0 cm of PM distance in early-stage disease,while PM distance was not associated with long-term survival in later and more aggressive stages of disease because more advanced GC is a systemic disease.Different types of patients should be considered for removal of an individualized PM distance intra-operatively.We developed a universally applicable prediction model for accurately determining the 1-year,3-year and 5-year DFS and OS of GC patients according to their preoperative clinicopathologic characteristics and PM distance.

Emergency exploratory laparotomy and radical gastrectomy in patients with gastric cancer combined with acute upper gastrointestinal bleeding

BACKGROUND Gastric cancer(GC)is a prevalent malignant tumor worldwide and ranks as the fourth leading cause of cancer-related mortality.Upper gastrointestinal bleeding(UGIB)is a frequent complication of GC.Radical gastrectomy and palliative therapy are widely used surgical procedures in the clinical management of GC.This study intends to probe the clinical efficacy and safety of radical gastrectomy and palliative therapy on the basis of exploratory laparotomy in patients with GC combined with UGIB,hoping to provide valuable information to aid patients in selecting the appropriate surgical intervention.AIM To investigate the clinical efficacy and safety of exploratory laparotomy^(+)radical gastrectomy and palliative therapy in patients with GC and UGIB combined.METHODS A total of 89 GC patients admitted to the First Affiliated Hospital of the University of South China between July 2018 and July 2020 were selected as participants for this study.The 89 patients were divided into two groups:radical resection group(n=46)treated with exploratory laparotomy^(+)radical gastrectomy and Palliative group(n=43)treated with palliative therapy.The study compared several variables between the two groups,including surgical duration,intraoperative blood transfusion volume,postoperative anal exhaust time,off-bed activity time,length of hospitalization,and incidence of complications such as duodenal stump rupture,anastomotic obstruction,and postoperative incision.Additionally,postoperative immune function indicators(including CD3^(+),CD4^(+),CD8^(+),CD4^(+)/CD8^(+),and CD3^(+)/HLADR^(+)),immunoglobulin(IgG and IgM),tumor markers(CEA,CA199,and CA125),and inflammatory factors(IL-6,IL-17,and TNF-α)were assessed.The surgical efficacy and postoperative quality of life recovery were also evaluated.The patients were monitored for survival and tumor recurrence at 6 mo,1 year,and 2 years post-surgery.RESULTS The results indicated that the duration of operation time and postoperative hospitalization did not differ between the two surgical procedures.However,patients in the radical resection group exhibited shorter intraoperative blood loss,anus exhaust time,off-bed activity time,and inpatient activity time than those in the Palliative group.Although there was no substantial difference in the occurrence of postoperative complications,such as duodenal stump rupture and anastomotic obstruction,between the radical resection group and Palliative group(P>0.05),the radical resection group exhibited higher postoperative immune function indicators(including CD3^(+),CD4^(+),CD8^(+),etc.)and immunoglobulin levels(IgG,IgM)than the Palliative group,while tumor markers and inflammatory factors levels were lower than those in the radical resection group.Additionally,surgical efficacy,postoperative quality of life,and postoperative survival rates were higher in patients who underwent radical gastrectomy than in those who underwent palliative therapy.Moreover,the probability of postoperative tumor recurrence was lower in the radical gastrectomy group compared to the palliative therapy group,and these differences were all statistically significant(P<0.05).CONCLUSION Compared to palliative therapy,exploratory laparotomy^(+)radical gastrectomy can improve immune function,reduce the levels of tumor markers and inflammatory factors,improve surgical efficacy,promote postoperative quality of life recovery,enhance survival rates,and attenuate the probability of tumor recurrence.

A comparative study of totally laparoscopic distal gastrectomy versus laparoscopic-assisted distal gastrectomy in gastric cancer patients: Short-term operative outcomes at a high-volume center

Objective： Laparoscopic gastrectomy has been established as a standard treatment for early gastric cancer, and its use is increasing recently. Compared with the conventional laparoscopy-assisted distal gastrectomy （LADG）, totally laparoscopic distal gastrectomy （TLDG） involves intracorporeal reconstruction, which can avoid the additional incision, resulting in pain reduction and early recovery. This study aimed to compare the short-term postoperative outcomes of TLDG vs. LADG in gastric cancer in a high-volume center.Methods： A retrospective cohort study was conducted on 1,322 patients who underwent laparoscopic distal gastrectomy from June 2012 to June 2017 at the National Cancer Center, Korea. LAD G was performed in the early period before July 2015, and TLDG was applied in the later period. Postoperative short-term outcomes were compared in terms of complication and clinical course between the two groups. Pain score was measured by rating the pain intensity from 0 to 10 points on postoperative day （POD） 1 and 3. Results： A total of 667 patients underwent LADG and 655 patients underwent TLDG. Clinieopathologic characteristics were not different in both groups. Intraoperative estimated blood loss （EBL） was significantly lower in the TLDG group （P〈0.001）. Postoperative pain scores were significantly lower in the TLDG group than in the LADG group on POD 1 （5.1±1.5 vs. 4.8±1.4, P=0.015）. First flatus passage after operation was significantly earlier in the TLDG group （3.4±0.8 d vs. 3.2±0.6 d, P〈0.001）. There were no differences in postoperative complications and hospital stay between the two groups. Conclusions： Based on the reported short-term postoperative outcomes, TLDG is safe and feasible as well as LADG. Moreover, compared with LADG, TLDG can reduce intraoperative EBL and postoperative pain and enhance the bowel motility in gastric cancer surgery.

Progression of remnant gastric cancer is associated with duration of follow-up following distal gastrectomy

AIM: To re-evaluate the recent clinicopathological features of remnant gastric cancer (RGC) and to develop desirable surveillance programs. METHODS: Between 1997 and 2008, 1149 patients underwent gastrectomy for gastric cancer at the Department of Digestive Surgery, Kyoto Prefectural University of Medicine, Japan. Of these, 33 patients underwent gastrectomy with lymphadenectomy for RGC. Regarding the initial gastric disease, there were 19 patients with benign disease and 14 patients with gastric cancer. The hospital records of these patients were reviewed retrospectively. RESULTS: Concerning the initial gastric disease, the RGC group following gastric cancer had a shorter interval [P < 0.05; gastric cancer vs benign disease: 12 (2-22) vs 30 (4-51) years] and were more frequently reconstructed by Billroth-Ⅰ procedure than those following benign lesions (P < 0.001). Regarding reconstruction, RGC following Billroth-Ⅱ reconstruction showed a longer interval between surgical procedures [P < 0.001; Billroth-Ⅱ vs Billroth-Ⅰ: 32 (5-51) vs 12 (2-36) years] and tumors were more frequently associated with benign disease (P < 0.001) than those following Billroth-Ⅰ reconstruction. In tumor location of RGC, after Billroth-Ⅰ reconstruction, RGC occurred more frequently near the suture line and remnant gastric wall. After Billroth-Ⅱ reconstruction, RGC occurred more frequently at the anastomotic site. The duration of follow-up was significantly associated with the stage of RGC (P < 0.05). Patients diagnosed with early stage RGC such as stage Ⅰ-Ⅱ tended to have been followed up almost every second year. CONCLUSION: Meticulous follow-up examination and early detection of RGC might lead to a better prognosis. Based on the initial gastric disease and the procedure of reconstruction, an appropriate follow-up interval and programs might enable early detection of RGC.

Treatment of gastric remnant cancer post distal gastrectomy by endoscopic submucosal dissection using an insulation-tipped diathermic knife

AIM: To evaluate the effectiveness of endoscopic submucosal dissection using an insulation-tipped diathermic knife (IT-ESD) for the treatment of patients with gastric remnant cancer. METHODS: Thirty-two patients with early gastric cancer in the remnant stomach, who underwent distal gastrectomy due to gastric carcinoma, were treated with endoscopic mucosal resection (EMR) or ESD at Sumitomo Besshi Hospital and Shikoku Cancer Center in the 10-year period from January 1998 to December 2007, including 17 patients treated with IT-ESD. Retrospectively, patient backgrounds, the one-piece resection rate, complete resection (CR) rate, operation time, bleeding rate, and perforation rate were compared between patients treated with conventional EMR and those treated with IT-ESD. RESULTS: The CR rate (40% in the EMR group vs 82% in the IT-ESD group) was significantly higher in the IT-ESD group than in the EMR group; however, the operation time was significantly longer for the IT- ESD group (57.6 ± 31.9 min vs 21.1 ± 12.2 min). No significant differences were found in the rate of underlying cardiopulmonary disease (IT-ESD group, 12% vs EMR group, 13%), one-piece resection rate (100% vs 73%), bleeding rate (18% vs 6.7%), and perforation rate (0% vs 0%) between the two groups. CONCLUSION: IT-ESD appears to be an effective treatment for gastric remnant cancer post distal gastrectomy because of its high CR rate. It is useful for histological confirmation of successful treatment. Thelong-term outcome needs to be evaluated in the future.

Radical gastrectomy for D2 distal gastric cancer

Patient＇s information The patient is a 56-year-old man who visited our hospital for ＂repeated epigastric pain for more than two months.＂ Physical examination showed nearly pale appearance; abdomen was soft and no mass palpable; left supraclavicular lymph node （-）; and digital rectal examination （-）.

Effect on changes of blood coagulation function, cytokines and immune function in patients undergoing laparoscopic radical gastrectomy for gastric cancer

Objective:To explore the changes of coagulation function, cytokines and T lymphocyte in patients undergoing laparoscopic radical gastrectomy for gastric cancer and its clinical significance.Methods: 40 cases of laparoscopic radical gastrectomy for gastric cancer patients and 40 cases of open radical gastrectomy for gastric cancer patients in our hospital were selected to detect and investigate the perioperative coagulation function [APTT (activated partial thromboplastin time), FIB (fibrinogen), and PLT (platelet)], cytokines [CRP (C reactive protein), IL-6 (IL-6) and TNF-alpha (Tumor necrosis factor-alpha)] and T lymphocytes (CD4+, CD8+ and CD4+/CD8+) changes and clinical meaning of patients in the two groups.Results: The coagulation function related indicators, cytokines and T lymphocytes of the two groups before treatment did not change significantly (P>0.05). 1 d after operation, blood coagulation, TNF-alpha, CD4+ and CD4+/CD8+ levels were significantly lower than that before operation in two groups of patients (P<0.05), while IL-6, CRP and CD8+ were significantly higher than that before the operation (P<0.05), and the index change in open group was more obvious. 3 d after surgery, the APTT, IL-6, CRP, CD4+, CD8+ and PLT levels in two group patients were significantly lower than that 1 d after surgery, while FIB, TNF-alpha and CD4+/CD8+ were significantly higher than that 1 d after surgery;blood coagulation index, TNF-alpha and CD4+ and CD4+/CD8+ were significantly lower in the laparotomy group patients than in laparoscopic group, while IL-6, CRP and CD8+ were significantly higher than the laparoscopic group (P<0.05). 5 d after operation, the APTT, TNF-alpha, FIB, CD4+, CD4+/CD8+ and PLT in two groups were significantly higher than that 3 d after surgery (P<0.05), while IL-6, CRP and CD8+ levels were significantly lower than that of 3 d after surgery (P<0.05);blood coagulation index, TNF-alpha and CD4+ and CD4+/CD8+ in the laparotomy group patients were significantly lower than laparoscopic group (P<0.05), while IL-6, CRP and CD8+ were significantly higher than the laparoscopic group (P<0.05).Conclusions: Radical resection of gastric cancer can cause coagulation disorder, inhibit the immune function and inflammatory reaction, and gradually recover with the passage of time;Compared with open surgery, laparoscopic radical gastrectomy have smaller impact on patients and recovery faster.

Neoadjuvant chemoradiotherapy followed by laparoscopic distal gastrectomy in advanced gastric cancer: A case report and review of literature

BACKGROUND The laparoscopic technique has been widely applied for early gastric cancer,with the advantages of minimal invasion and quick recovery.However,there is no report about the safety and oncological outcome of laparoscopic gastrectomy with D2 lymph node dissection for patients after neoadjuvant chemoradiotherapy.CASE SUMMARY A 60-year-old man was diagnosed with advanced distal gastric cancer,cT4aN1M0 stage III.The neoadjuvant chemoradiotherapy was performed based on the regimen of gross tumor volume 50G y/25 f and clinical target volume 45 Gy/25 f,as well as concurrent S-160 mg Bid.Then laparoscopic distal gastrectomy with D2 lymph node dissection was undertaken successfully for him after achieving partial response evaluated by radiological examination.The patient recovered smoothly without moderate or severe postoperative complications.The postoperative pathological stage was ypT3N0M0 with American Joint Committee on Cancer tumor regression grade 1.He was still in good condition after 5 years of follow-up.CONCLUSION Neoadjuvant chemoradiotherapy followed by laparoscopic technique could be applicable and may achieve satisfactory oncological outcomes.Our finding requires further validation by cohort studies.

Clinical observation of laparoscopic radical gastrectomy for advanced gastric cancer

Objective: To explore the clinical efficacy of laparoscopic radical gastrectomy and traditional open radical gastrectomy for advanced gastric cancer. Methods: 116 patients with advanced gastric cancer in our hospital were randomly selected, including 55 cases in the experimental group and 61 cases in the control group. The clinical effects, CEA, CA-199, AFP and postoperative complications of the two groups were compared. Results: The indexes of operation and post-operation (average operation time, incision length, exhaust time, intraoperative bleeding volume, hospital stay, enteral nutrition time), and the total number of lymph nodes dissected in the experimental group was less than that in the control group (P < 0.05). There was no difference in CEA, CA-199 and AFP before operation and 1 month after operation. The incidence of complications in laparoscopic group was 9.1% lower than that in control group (27.9%). Conclusion: Laparoscopic radical gastrectomy has many advantages in the treatment of gastric cancer, which can effectively reduce complications and is worth promoting.

Harnessing interventions during the immediate perioperative period to improve the long-term survival of patients following radical gastrectomy

Although the incidence and mortality of gastric cancer(GC)have been decreasing steadily worldwide,especially in East Asia,the disease burden of this malignancy is still very heavy.Except for tremendous progress in the management of GC by multidisciplinary treatment,surgical excision of the primary tumor is still the cornerstone intervention in the curative-intent treatment of GC.During the relatively short perioperative period,patients undergoing radical gastrectomy will suffer from at least part of the following perioperative events:Surgery,anesthesia,pain,intraoperative blood loss,allogeneic blood transfusion,postoperative complications,and their related anxiety,depression and stress response,which have been shown to affect long-term outcomes.Therefore,in recent years,studies have been carried out to find and test interventions during the perioperative period to improve the long-term survival of patients following radical gastrectomy,which will be the aim of this review.

Multifactor analysis of the technique in total laparoscopic gastric cancer

BACKGROUND Esophageal gastric anastomosis is a common surgical technique used to treat patients with gastric cancer who undergo total gastrectomy.However,using simple anastomosis techniques alone may not meet the needs of patients in some cases and can lead to complications such as anastomotic stenosis and ulceration.In order to overcome these issues and improve patient prognosis,muscle flap reconstruction technique has emerged.Muscle flap reconstruction is a method of improving gastric-esophageal anastomosis by transplanting muscle tissue.By covering the anastomotic site with muscle tissue,it not only enhances the stability of the anastomosis site but also increases blood supply,promoting healing and recovery of the anastomosis.Therefore,the use of muscle flap reconstruction technique in esophageal gastric anastomosis during total gastrectomy for gastric cancer is increasingly widely applied.AIM To determine the effectiveness of esophagogastric anastomosis using the muscle flap reconstruction technology in total abdominal gastrectomy for gastric cancer and perform follow-up experiments to understand the factors affecting patients’prognosis.METHODS The study subjects were 60 patients with gastric cancer who were admitted to our hospital between October 2018 and January 2022.All patients underwent esopha-gogastric anastomosis using the double muscle flap reconstruction technology in total abdominal gastrectomy.Perioperative indicators were determined,and INTRODUCTION Gastric cancer is one of the most common tumors of the digestive system worldwide.Although gastric cancer may not have significant manifestations in the early stage,as the disease progresses,systemic symptoms such as emaciation,anemia,and gastric perforation are observed[1].Surgery is the main treatment strategy for gastric cancer.With recent advances in total laparoscopy,total laparoscopic radical resection has gradually become an important treatment strategy for gastric cancer.Conventional laparoscopic surgery may require at least 5-6 incisions,whereas total laparoscopic surgery requires only 3-4 small incisions,decreasing surgical trauma and postoperative pain[2].Furthermore,because total laparoscopic surgery is less invasive than conventional laparoscopic surgery,patients can generally return to normal living and working conditions more quickly[3].Moreover,total laparoscopic surgery does not leave obvious surgical scars;therefore,it is advantageous for patients who pay attention to appearance[4].Esophagogastrostomy is a method used to repair gastrointestinal anastomosis,called the“double muscle valve”.This technique requires folding the fundus of the stomach,followed by sealing it with two layers of tissue,forming a structure similar to a valve.The application of esophagogastrostomy to total laparoscopic radical resection for gastric cancer can effectively decrease the incidence of complications such as anastomotic incontinence and bile reflux and improve the surgical cure rate and postoperative quality of life,which is a recent topic of interest for surgeons.At present,systematic multivariate analyses of the application effects of esophagogastrostomy in total laparoscopic surgery for gastric cancer and their effects on prognosis remain scarce[5].In the present study,we conducted surgery and postoperative follow-up of patients with gastric cancer and collected relevant clinical data for esophagogastric anastomosis during postoperative resection for gastric cancer to ACKNOWLEDGEMENTS I would like to express my sincere thanks to all those who participated in the manuscript.

Roux-en-Y versus BillrothⅠreconstruction after distal gastrectomy for gastric cancer:A meta-analysis

AIM:To conduct a meta-analysis to compare Rouxen-Y(R-Y) gastrojejunostomy with gastroduodenal Billroth Ⅰ(B-Ⅰ) anastomosis after distal gastrectomy(DG) for gastric cancer.METHODS:A literature search was performed to identify studies comparing R-Y with B-Ⅰ after DG for gastric cancer from January 1990 to November 2012 in Medline,Embase,Science Citation Index Expanded and the Cochrane Central Register of Controlled Trials in The Cochrane Library.Pooled odds ratios(OR) or weighted mean differences(WMD) with 95%CI were calculated using either fixed or random effects model.Operative outcomes such as operation time,intraoperative blood loss and postoperative outcomes such as anastomotic leakage and stricture,bile reflux,remnant gastritis,reflux esophagitis,dumping symptoms,delayed gastric emptying and hospital stay were the main outcomes assessed.Meta-analyses were performed using RevMan 5.0 software(Cochrane library).RESULTS:Four randomized controlled trials(RCTs) and 9 non-randomized observational clinical studies(OCS) involving 478 and 1402 patients respectively were included.Meta-analysis of RCTs revealed that R-Y reconstruction was associated with a reduced bile reflux(OR 0.04,95%CI:0.01,0.14;P < 0.00 001) and remnant gastritis(OR 0.43,95%CI:0.28,0.66;P = 0.0001),however needing a longer operation time(WMD 40.02,95%CI:13.93,66.11;P = 0.003).Metaanalysis of OCS also revealed R-Y reconstruction had a lower incidence of bile reflux(OR 0.21,95%CI:0.08,0.54;P = 0.001),remnant gastritis(OR 0.18,95%CI:0.11,0.29;P < 0.00 001) and reflux esophagitis(OR 0.48,95%CI:0.26,0.89;P = 0.02).However,this reconstruction method was found to be associated with a longer operation time(WMD 31.30,95%CI:12.99,49.60;P = 0.0008).CONCLUSION:This systematic review point towards some clinical advantages that are rendered by R-Y compared to B-Ⅰ reconstruction post DG.However there is a need for further adequately powered,welldesigned RCTs comparing the same.

Comparison between uncut Roux-en-Y and Roux-en-Y reconstruction after distal gastrectomy for gastric cancer: A meta-analysis

AIM To compare uncut Roux-en-Y(U-RY) gastrojejunostomy with Roux-en-Y(RY) gastrojejunostomy after distal gastrectomy(DG) for gastric cancer.METHODS A literature search was conducted in Pubmed, Embase, Web of Science, Cochrane Library, Science Direct, Chinese National Knowledge Infrastructure, Wanfang, and China Science and Technology Journal Database to identify studies comparing U-RY with RY after DG for gastric cancer until the end of December 2017. Pooled odds ratio or weighted mean difference with 95% confidence interval was calculated using either fixed-or random-effects models. Perioperative outcomes such as operative time, intraoperative blood loss, and hospital stay; postoperative complications such as anastomotic bleeding, stricture and ulcer, reflux gastritis/esophagitis, delayed gastric emptying, and Roux stasis syndrome; and postoperative nutritional status(serum hemoglobin, total protein, and albumin levels) were the main outcomes assessed. Metaanalyses were performed using RevM an 5.3 software.RESULTS Two randomized controlled trials and four nonrandomized observational clinical studies involving 403 and 488 patients, respectively, were included. The results of the meta-analysis showed that operative time [weighted mean difference(WMD):-12.95; 95%CI:-22.29 to-3.61; P = 0.007] and incidence of reflux gastritis/esophagitis(OR: 0.40; 95%CI: 0.20-0.80; P = 0.009), delayed gastric emptying(OR: 0.29; 95%CI: 0.14-0.61; P = 0.001), and Roux stasis syndrome(OR: 0.14; 95%CI: 0.04-0.50; P = 0.002) were reduced; and the level of serum albumin(WMD: 0.71; 95%CI: 0.24-1.19; P = 0.003) was increased in patients undergoing U-RY reconstruction compared with those undergoing RY reconstruction. No differences were found with respect to intraoperative blood loss, hospital stay, anastomotic bleeding, anastomotic stricture, anastomotic ulcer, the levels of serum hemoglobin, and serum total protein. CONCLUSION U-RY reconstruction has some clinical advantages over RY reconstruction after DG.

Roux-en-Y reconstruction does not require gastric decompression after radical distal gastrectomy

AIM: To determine whether routine nasogastric (NG) decompression benefitted patients undergoing radical gastric surgery. METHODS: Between January 1998 and December 2008, 519 patients who underwent distal gastrectomy for gastric cancer were retrospectively divided into 2 time-period cohorts; those treated with Billroth Ⅱ (BⅡ) reconstruction in the first 6 years and those with Roux-en-Y (RY) reconstruction in the last 5 years. In the latter group, the patients were further divided into 2 subgroups; with and without nasogastric decompression.RESULTS: Postoperatively, there were no significant differences in the number of anastomotic leaks between the 3 groups. In the tubeless RY group, time to semiliquid diet was significantly shorter than in the other 2 groups (4.4 d ± 1.4 d vs 7.2 d ± 1.3 d and 5.9 d ± 1.2 d, P = 0.005). The length of postoperative stay was significantly increased in patients with BⅡ reconstruction compared with patients with RY reconstruction with/without NG decompression (15.4 d ± 4.3 d in BⅡ group vs 12.6 d ± 3.1 d in decompressed RY and 11.4 d ± 3.4 d in the tubeless RY group, P = 0.035). The postoperative pneumonia rate was lowest in the tubeless group and highest in the BⅡ group (1.4% vs 4.6%, P = 0.01). Severe sore throat was noted in 59 (20.7%) members of the BⅡ group, 18 (17.4%) members of the decompressed RY group and 6 (4.2%) members of the tubeless RY group. Fewer patients in the tubeless group complained of severe sore throat (P = 0.001). CONCLUSION: This study provides support for abandoning routine NG decompression in patients undergoing subtotal gastrectomy with Roux-en-Y gastrojejunostomy.

Surgical resection of gastric stump cancer following proximal gastrectomy for adenocarcinoma of the esophagogastric junction

BACKGROUND Proximal gastrectomy(PG) is performed widely as a function-preserving operation for early gastric cancer located in the upper third of the stomach and is an important function-preserving approach for esophagogastric junction(EGJ)adenocarcinoma. The incidence of gastric stump cancer(GSC) after PG is increasing. However, little is known about the GSC following PG because very few studies have been conducted on the disease.AIM To clarify clinicopathologic features, perioperative complications, and long-term survival rates after the resection of GSC following PG.METHODS Data for patients with GSC following PG for adenocarcinoma of the EGJ diagnosed between January 1998 and December 2016 were retrospectively reviewed. Multivariate analysis was performed to identify factors associated with overall survival(OS). GSC was defined in accordance with the Japanese Gastric Cancer Association.RESULTS A total of 35 patients were identified. The median interval between the initial PGand resection of GSC was 4.9(range 0.7-12) years. In 21 of the 35 patients, the tumor was located in a nonanastomotic site of the gastric stump. Total gastrectomy was performed in 27 patients; the other 8 underwent partial gastrectomy. Postoperative complications occurred in 6 patients(17.1%). The tumor stage according to the depth of tumor invasion was T1 in 6 patients, T2 in3 patients, T3 in 9 patients, and T4 in 17 patients. Lymph node metastasis was observed in 18 patients. Calculated 1-, 3-, and 5-year OS rates were 86.5%, 62.3%,and 54.2%, respectively. Multivariate analysis showed advanced T stage to be associated with OS.CONCLUSION This study reveals the characteristics of GSC following PG for adenocarcinoma of the EGJ and suggests that a surgical approach can lead to a satisfactory outcome.

Gastric cancer arising from the remnant stomach after distal gastrectomy:A review

Gastric stump carcinoma was initially reported by Balfore in 1922,and many reports of this disease have since been published. We herein review previous reports of gastric stump carcinoma with respect to epidemiology,carcinogenesis,Helicobacter pylori(H. pylori) infection,Epstein-Barr virus infection,clinicopathologic characteristics and endoscopic treatment. In particular,it is noteworthy that no prognostic differences are observed between gastric stump carcinoma and primary upper third gastric cancer. In addition,endoscopic submucosal dissection has recently been used to treat gastric stump carcinoma in the early stage. In contrast,many issues concerning gastric stump carcinoma remain to be clarified,including molecular biological characteristics and the carcinogenesis of H.pylori infection.We herein review the previous pertinent literature and summarize the characteristics of gastric stump carcinoma reported to date.

Initial experience of single-incision plus one port left-side approach totally laparoscopic distal gastrectomy with uncut Roux-en-Y reconstruction

BACKGROUND Single incision plus one port left-side approach(SILS+1/L)totally laparoscopic distal gastrectomy(TLDG)is an emerging technique for the treatment of gastric cancer.Reduced port laparoscopic gastrectomy has a number of potential advantages for patients compared with conventional laparoscopic gastrectomy:relieving postoperative pain,shortening hospital stay and offering a better cosmetic outcome.Nevertheless,there are no previous reports on the use of SILS+1/L TLDG with uncut Roux-en-Y(uncut R-Y)reconstruction.AIM To investigate the initial feasibility of SILS+1/L TLDG with uncut Roux-en-Y digestive tract reconstruction(uncut R-Y reconstruction)to treat distal gastric cancer.METHODS A total of 21 patients who underwent SILS+1/L TLDG with uncut R-Y reconstruction for gastric cancer were enrolled.All patients were treated at The Second Hospital of Shandong University.Reconstructions were performed intracorporeally with 60 mm endoscopic linear stapler and 45 mm no-knife stapler.The clinicopathological characteristics,surgical details,postoperative short-term outcomes,postoperative follow-up upper gastrointestinal radiography findings and endoscopy results were analyzed retrospectively.RESULTS All SILS+1/L operations were performed by SILS+1/L TLDG successfully.The patient population included 13 men and 8 women with a mean age of 48.2 years(ranged from 40 years to 70 years)and median body mass index of 22.8 kg/m^2.There were no conversions to open laparotomy,and no other port was placed.The mean operation time was 146 min(ranged 130-180 min),and the estimated mean blood loss was 54 mL(ranged 20-110 mL).The mean duration to flatus and discharge was 2.3(ranged 1-3.5)and 7.3(ranged 6-9)d,respectively.The mean number of retrieved lymph nodes was 42(ranged 30-47).Two patients experienced mild postoperative complications,including surgical site infection(wound at the navel incision)and mild postoperative pancreatic fistula(grade A).Follow-up upper gastrointestinal radiography and endoscopy were carried out at 3 mo postoperatively.No patients experienced moderate or severe food stasis,alkaline gastritis or bile reflux during the follow-up period.No recanalization of the biliopancreatic limb was found.CONCLUSION SILS+1/L TLDG with uncut R-Y reconstruction could be safely performed as a reduced port surgery.