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.

Comparison efficacy and safety of total laparoscopic gastrectomy and laparoscopically assisted total gastrectomy in treatment of gastric cancer

BACKGROUND The development of laparoscopic technology has provided a new choice for surgery of gastric cancer(GC),but the advantages and disadvantages of laparoscopic total gastrectomy(LTG)and laparoscopic-assisted total gastrectomy(LATG)in treatment effect and safety are still controversial.The purpose of this study is to compare the efficacy and safety of the two methods in the treatment of GC,and to provide a basis for clinical decision-making.AIM To compare the efficacy of totally LTG(TLTG)and LATG in the context of radical gastrectomy for GC.Additionally,we investigated the safety and feasibility of the total laparoscopic esophagojejunostomy technique.METHODS Literature on comparative studies of the above two surgical methods for GC(TLTG group and LATG group)published before September 2022 were searched in the PubMed,Web of Science,Wanfang Database,CNKI,and other Chinese and English databases.In addition,the following search keywords were used:Gastric cancer,total gastrectomy,total laparoscopy,laparoscopy-assisted,esophagojejunal anastomosis,gastric/stomach cancer,total gastrectomy,totally/completely laparoscopic,laparoscopic assisted/laparoscopy assisted/laparoscopically assisted,and esophagojejunostomy/esophagojejunal anastomosis.Review Manager 5.3 software was used for the meta-analysis after two researchers independently screened the literature,extracted the data,and evaluated the risk of bias in the included studies.RESULTS After layer-by-layer screening,258 pieces of literature were recovered,and 11 of those pieces were eventually included.This resulted in a sample size of 2421 instances,with 1115 cases falling into the TLTG group and 1306 cases into the LATG group.Age or sex differences between the two groups were not statistically significant,according to the meta-analysis,however the average body mass index of the TLTG group was considerably higher than that of the LATG group(P=0.01).Compared with those in the LATG group,the incision length in the TLTG group was significantly shorter(P<0.001),the amount of intraoperative blood loss was significantly lower(P=0.003),the number of lymph nodes removed was significantly greater(P=0.04),and the time of first postoperative feeding and postoperative hospitalization were also significantly shorter(P=0.03 and 0.02,respectively).There were no significant differences in tumor size,length of proximal incisal margin,total operation time,anastomotic time,postoperative pain score,postoperative anal exhaust time,postoperative anastomosis-related complications(including anastomotic fistula,anastomotic stenosis,and anastomotic hemorrhage),or overall postoperative complication rate(P>0.05).CONCLUSION TLTG and esophagojejunostomy are safe and feasible.Compared with LATG,TLTG has the advantages of less trauma,less bleeding,easier access to lymph nodes,and faster postoperative recovery,and TLTG is also suitable for obese patients.

Clinical Application Analysis of Laparoscopic-Assisted Total Gastrectomy in the Surgical Treatment of Gastric Cancer

Objective:To investigate the clinical application effect of laparoscopic-assisted total gastrectomy in the surgical treatment of gastric cancer.Methods:The clinical data of 86 COPD patients included in the study were collected and divided into 43 cases each in Groups A and B using the randomization method,with open total gastrectomy in Group A and laparoscopic-assisted total gastrectomy in Group B.The clinical indexes,pain levels,and complications of patients in the two groups were observed in combination with the indexes.Results:The baseline data of the two groups of patients were not statistically significant(all P>0.05);the operation time,incision length,first flatulence time,and hospitalization time of patients in Group B were shorter than those in Group A(all P=0.000);the NRS scores of patients in Group B on the 1st postoperative day and the 2nd postoperative day were significantly lower than those in Group A(t=23.443,t=28.784,all P=0.000);the total complication rate of patients in Group B(1;2.33%)was significantly lower than that of Group A(9;20.94%)(χ^(2)=7.242,P=0.007).Conclusion:In the surgical treatment of gastric cancer,laparoscopic-assisted total gastrectomy can promote patients’recovery,reduce patients’pain,and lower the probability of complications.

Impact of preoperative therapy on surgical outcomes of laparoscopic total gastrectomy for gastric/gastroesophageal junction cancer

Objective: As laparoscopic surgery is widely applied for primarily treated gastric cancer(GC)/gastroesophageal junction cancer(GEJC) and gains many advantages, the feasibility of laparoscopic total gastrectomy(LTG) for GC/GEJC patients who have received preoperative therapy(PT) has come to the fore. This study aims to analyze the safety and feasibility of LTG after PT for GC/GEJC patients.Methods: We retrospectively analyzed the data of 511 patients with GC/GEJC undergoing LTG, of which 405received LTG(LTG group) and 106 received PT+LTG(PT-LTG group) at Nanfang Hospital between June 2018and September 2022. The surgical outcomes were compared between the two groups.Results: The surgical duration was significantly longer in the PT-LTG group(P<0.001), while the incidence of intraoperative complications(P=1.000), postoperative complications(LTG group vs. PT-LTG group: 26.2% vs.23.6%, P=0.587), the classification of complication severity(P=0.271), and postoperative recovery was similar between two groups. Notably, the incidence of anastomotic complications of esophagojejunostomy was also comparable between the two groups(LTG group vs. PT-LTG group: 5.9% vs. 5.7%, P=0.918). The univariate and multivariate analysis confirmed that positive proximal margin [positive vs. negative: odds ratio(OR)=14.094, 95%confidence interval(95% CI): 2.639-75.260, P=0.002], rather than PT, has an impact on anastomotic complications after LTG(OR=0.945, 95% CI: 0.371-2.408, P=0.905).Conclusions: PT did not increase the surgical risk of LTG for GC/GEJC. Therefore, considering the positive effect of PT on long-term survival, the broader application of PT and LTG for GC/GEJC is supported by our findings.

Efficacy and safety of laparoscopic vs open gastrectomy after neoadjuvant therapy for locally advanced gastric cancer

BACKGROUND Laparoscopic gastrectomy(LG)is widely accepted as a minimally invasive approach for the treatment of early gastric cancer.However,its role in locally advanced gastric cancer(LAGC)after neoadjuvant therapy(NAT)remains controversial.This study aimed to compare the efficacy and safety of LG vs open gastrectomy(OG)after NAT for the treatment of LAGC.AIM To compare the efficacy and safety of LG vs OG after NAT for LAGC.METHODS We conducted a prospective study of 76 patients with LAGC who underwent NAT followed by LG(n=38)or OG(n=38)between 2021 and 2023.The primary endpoint was overall survival(OS),and the secondary endpoints were diseasefree survival(DFS),surgical complications,and quality of life(QOL).RESULTS The two groups had comparable baseline characteristics,with a median follow-up period of 24 mo.The 3-year OS rates in the LG and OG groups were 68.4%and 60.5%,respectively(P=0.42).The 3-year DFS rates in the LG and OG groups were 57.9%and 50.0%,respectively(P=0.51).The LG group had significantly less blood loss(P<0.001),a shorter hospital stay(P<0.001),and a lower incidence of surgical site infection(P=0.04)than the OG group.There were no significant differences in other surgical complications between the groups,including anastomotic leakage,intra-abdominal abscess,or wound dehiscence.The LG group had significantly better QOL scores than the OG group regarding physical functioning,role functioning,global health status,fatigue,pain,appetite loss,and body image at 6 months postoperatively(P<0.05).CONCLUSION LG after NAT is a viable and safe alternative to OG for the treatment of LAGC,with similar survival outcomes and superior short-term recovery and QOL.LG patients had less blood loss,shorter hospitalizations,and a lower incidence of surgical site infections than OG patients.Moreover,the LG group had better QOL scores in multiple domains 6 mo postoperatively.Therefore,LG should be considered a valid option for patients with LAGC who undergo NAT,particularly for those who prioritize postoperative recovery and QOL.

Laparoscopic vs open total gastrectomy for gastric cancer:A meta-analysis

AIM:To conduct a meta-analysis comparing laparoscopic total gastrectomy(LTG)with open total gastrectomy(OTG)for the treatment of gastric cancer.METHODS:Major databases such as Medline(PubMed),Embase,Academic Search Premier(EBSCO),Science Citation Index Expanded and the Cochrane Central Register of Controlled Trials(CENTRAL)in The Cochrane Library were searched for studies comparing LTG and OTG from January 1994 to May 2013.Evaluated endpoints were operative,postoperative and oncological outcomes.Operative outcomes included operative time and intraoperative blood loss.Postoperative recovery included time to first fatus,time to first oral intake,hospital stay and analgesics use.Postoperative complications comprised morbidity,anastomotic leakage,anastomotic stenosis,ileus,bleeding,abdominal abscess,wound problems and mortality.Oncological outcomes included positive resection margins,number of retrieved lymph nodes,and proximal and distal resection margins.The pooled effect was calculated using either a fixed effects or a random effects model.RESULTS:Fifteen non-randomized comparative studies with 2022 patients were included(LTG-811,OTG-1211).Both groups had similar short-term oncological outcomes,analgesic use(WMD-0.09;95%CI:-2.39-2.20;P=0.94)and mortality(OR=0.74;95%CI:0.24-2.31;P=0.61).However,LTG was associated with a lower intraoperative blood loss(WMD-201.19 mL;95%CI:-296.50--105.87 mL;P<0.0001)and overall complication rate(OR=0.73;95%CI:0.57-0.92;P=0.009);fewer wound-related complications(OR=0.39;95%CI:0.21-0.72;P=0.002);a quicker recovery of gastrointestinal motility with shorter time to frst fatus(WMD-0.82;95%CI:-1.18--0.45;P<0.0001)and oral intake(WMD-1.30;95%CI:-1.84--0.75;P<0.00001);and a shorter hospital stay(WMD-3.55;95%CI:-5.13--1.96;P<0.0001),albeit with a longer operation time(WMD 48.25 min;95%CI:31.15-65.35;P<0.00001),as compared with OTG.CONCLUSION:LTG is safe and effective,and may offer some advantages over OTG in the treatment of gastric cancer.

Perioperative outcomes of transvaginal specimen extraction laparoscopic total gastrectomy and conventional laparoscopicassisted total gastrectomy

BACKGROUND Natural orifice specimen extraction surgery(NOSES)has emerged as a promising alternative compared to conventional laparoscopic-assisted total gastrectomy(LATG)for treating gastric cancer(GC).However,evidence regarding the efficacy and safety of NOSES for GC surgery is limited.This study aimed to compare the safety and feasibility,in addition to postoperative complications of NOSES and LATG.METHODS Dual circular staplers were used in Roux-en-Y digestive tract reconstruction for transvaginal specimen extraction LATG,and its outcomes were compared with LATG in a cohort of 51 GC patients with tumor size≤5 cm.The study was conducted from May 2018 to September 2020,and patients were categorized into the NOSES group(n=22)and LATG group(n=29).Perioperative parameters were compared and analyzed,including patient and tumor characteristics,postoperative outcomes,and anastomosis-related complications,postoperative hospital stay,the length of abdominal incision,difference in tumor type,postoperative complications,and postoperative survival.RESULTS Postoperative exhaust time,operation duration,mean postoperative hospital stay,length of abdominal incision,number of specific staplers used,and Brief Illness Perception Questionnaire score were significant in both groups(P<0.01).In the NOSES group,the postoperative time to first flatus,mean postoperative hospital stay,and length of abdominal incision were significantly shorter than those in the LATG group.Patients in the NOSES group had faster postoperative recovery,and achieved abdominal minimally invasive incision that met aesthetic requirements.There were no significant differences in gender,age,tumor type,postoperative complications,and postoperative survival between the two groups.CONCLUSION The application of dual circular staplers in Roux-en-Y digestive tract reconstruction combined with NOSES gastrectomy is safe and convenient.This approach offers better short-term outcomes compared to LATG,while long-term survival rates are comparable to those of conventional laparoscopic surgery.

Efficacy of totally laparoscopic compared with laparoscopic-assisted total gastrectomy for gastric cancer: A meta-analysis

BACKGROUND Laparoscopic radical gastrectomy is currently the most common surgical approach for gastric cancer.The main difference between totally laparoscopic total gastrectomy(TLTG)and laparoscopic-assisted total gastrectomy(LATG)is the route of digestive tract reconstruction.However,TLTG is currently not widespread as the safety and feasibility of intracorporeal esophagojejunostomy is uncertain.AIM To compare the short-term efficacy of TLTG and LATG for radical gastrectomy of gastric cancer,and to determine the safety and feasibility of intracorporeal esophagojejunostomy.METHODS PubMed,EMBASE,and Web of Science databases were searched for all relevant articles regarding TLTG vs LATG for gastric cancer published up to October 1,2019.Inclusion and exclusion criteria were established.All the basic conditions of patients and important clinical data related to surgery were extracted,and a meta-analysis was performed with RevMan 5.3 software.RESULTS Eight studies involving a total of 1883 cases(869 cases in the TLTG group and 1014 cases in the LATG group)were included.Compared with the LATG group,reduced intraoperative blood loss(weighted mean difference=-35.37,95%CI:-61.69--9.06,P=0.008)and a larger number of retrieved lymph nodes(weighted mean difference=3.11,95%CI:-2.60-12.00,P=0.01)were found in the TLTG group.There were no significant differences in operating time,anastomotic time,tumor size,proximal resection margin length,postoperative pain score,time to first flatus,time to first oral intake,postoperative hospital stay,postoperative anastomosis-related complication rate and overall complication rate between the two groups(P>0.05).CONCLUSION Intracorporeal esophagojejunostomy is safe and feasible.TLTG has the advantages of being minimally invasive,reduced intraoperative blood loss and easier access to lymph nodes compared with LATG.Totally laparoscopic gastrectomy is likely to be the surgical trend for gastric cancer in the future.

Comparison of short-term efficacy between totally laparoscopic gastrectomy and laparoscopic assisted gastrectomy for elderly patients with gastric cancer

BACKGROUND Totally laparoscopic gastrectomy(TLG)entails both gastrectomy and gastrointestinal reconstruction under laparoscopy.Compared with laparoscopic assisted gastrectomy(LAG),TLG has been demonstrated in many studies to require a smaller surgical incision,result in a faster postoperative recovery and less pain and have comparable long-term efficacy,which has been a research hotspot in recent years.Whether TLG is equally safe and feasible for elderly patients remains unclear.AIM To compare the short-term efficacy of and quality of life(QOL)associated with TLG and LAG in elderly gastric cancer(GC)patients.METHODS The clinicopathological data of 462 elderly patients aged≥70 years who underwent LAG or TLG(including distal gastrectomy and total gastrectomy)between January 2017 and January 2022 at the Department of General Surgery,First Medical Center,Chinese PLA General Hospital were retrospectively collected.A total of 232 patients were in the LAG group,and 230 patients were in the TLG group.Basic patient information,clinicopathological characteristics,operation information and QOL data were collected to compare efficacy.Compared with those in the LAG group,intraoperative blood loss in the TLG group was significantly lower(P<0.001),and the time to first flatus and postoperative hospitalization time were significantly shorter(both P<0.001).The overall incidence of postoperative complications in the TLG group was significantly lower than that in the LAG group(P=0.01).Binary logistic regression results indicated that LAG and an operation time>220 min were independent risk factors for postoperative complications in elderly patients with GC(P<0.05).In terms of QOL,no statistically significant differences in various preoperative indicators were found between the LAG group and the LTG group(P>0.05).Compared with the laparoscopic-assisted total gastrectomy group,patients who received totally laparoscopic total gastrectomy had lower nausea and vomiting scores and higher satisfaction with their body image(P<0.05).Patients who underwent laparoscopic-assisted distal gastrectomy were more satisfied with their body image than patients in the totally laparoscopic distal gastrectomy group(P<0.05).CONCLUSION TLG is safe and feasible for elderly patients with GC and has outstanding advantages such as reducing intracorporeal blood loss,promoting postoperative recovery and improving QOL.

Laparoscopic vs open total gastrectomy for advanced gastric cancer following neoadjuvant therapy:A propensity score matching analysis

BACKGROUND Laparoscopic total gastrectomy(LTG)has drawn increasing attention over the years.Although LTG has shown surgical benefits compared to open TG(OTG)in early stage gastric cancer(GC),little is known about the surgical and oncological outcomes of LTG for advanced GC following neoadjuvant therapy(NAT).AIM To compare the long-and short-term outcomes of advanced GC patients who underwent LTG vs OTG following NAT.METHODS Advanced GC patients who underwent TG following NAT between April 2011 and May 2018 at the Cancer Hospital of the Chinese Academy of Medical Sciences were enrolled and stratified into two groups:LTG and OTG.Propensity score matching analysis was performed at a 1:1 ratio to overcome possible bias.RESULTS In total,185 patients were enrolled(LTG:78;OTG:109).Of these,138 were paired after propensity score matching.After adjustment for propensity score matching,baseline parameters were similar between the two groups.Compared to OTG,LTG was associated with a significantly shorter length of hospital stay(P=0.012).The rates of R0 resection,lymph node harvest,and postoperative morbidity did not significantly differ between the two groups.Overall survival(OS)outcomes were comparable between the two groups.Pathological T and N stages were found to be independent risk factors for OS.CONCLUSION LTG can be a feasible method for advanced GC patients following NAT,as it appears to be associated with better short-and comparable long-term outcomes compared to OTG.

Short and long-term outcomes between laparoscopic and open total gastrectomy for advanced gastric cancer after neoadjuvant chemotherapy

BACKGROUND Neoadjuvant chemotherapy(NACT)combined with surgery is regarded as an effective treatment for advanced gastric cancer(AGC).Laparoscopic surgery represents the mainstream of minimally invasive surgery.Currently,surgeons focus more on surgical safety and oncological outcomes of laparoscopic gastrectomy after NACT.Thus,we sought to evaluate short-and long-term outcomes between laparoscopic total gastrectomy(LTG)and open total gastrectomy(OTG)after NACT.AIM To compare the short and long-term outcomes between LTG and OTG for AGC after NACT.METHODS We retrospectively collected the clinicopathological data of 136 patients who accepted gastrectomy after NACT from June 2012 to June 2019,including 61 patients who underwent LTG and 75 who underwent OTG.Clinicopathological characteristics between the LTG and OTG groups showed no significant difference.SPSS 26.0,R software,and GraphPad PRISM 8.0 were used to perform statistical analyses.RESULTS Of the 136 patients included,eight acquired pathological complete response,and the objective response rate was 47.8%(65/136).The LTG group had longer operation time(P=0.015),less blood loss(P=0.003),shorter days to first flatus(P<0.001),and shorter postoperative hospitalization days(P<0.001).LTG spent more surgical cost than OTG(P<0.001),while total hospitalized cost of LTG was less than OTG(P<0.001).21(28.0%)patients in the OTG group and 14(23.0%)in the LTG group had 30-d postoperative complications,but there was no significant difference between the two groups(P=0.503).The 3-year overall survival(OS)rate was 60.6%and 64.6%in the LTG and OTG groups,respectively[hazard ratio(HR)=0.859,95%confidence interval(CI):0.522-1.412,P=0.546],while the 3-year disease-free survival(DFS)rate was 54.5%and 51.8%in the LTG and OTG group,respectively(HR=0.947,95%CI:0.582-1.539,P=0.823).Multivariate cox analysis showed that body mass index and pTNM stage were independent risk factors for OS while vascular invasion and pTNM stage were independent risk factors for DFS(P<0.05).CONCLUSION After NACT,LTG shows comparable 30-d postoperative morbidity as well as 3-year OS and DFS rate to OTG.We recommend that experienced surgeons select LTG other than OTG for proper AGC patients after NACT.

Totally Laparoscopic Total Gastrectomy with D2 Lymphadenectomy for Advanced Gastric Cancer

Introductions: Gastrectomy, which is the standard surgical procedure for gastric cancer, has gradually come to be performed laparoscopically. Laparoscopic distal gastrectomy (LDG) has been adopted gradually and performed for advanced gastric cancer. However, laparoscopic total gastrectomy (LTG) has not been as widely accepted as LDG due to technical difficulties, especially with reconstruction and proper D2 lymphadenectomy. The purpose of the current study was to determine the utility of TLTG with concomitant splenectomy and D2 lymphadenectomy (TLTGS) for advanced gastric cancer (AGC). Materials and Methods: Between January 2006 and May 2014, 10 consecutive patients who underwent TLTGS for AGC and 76 patients who underwent TLTG with D1 lymphadenectomy were included in this study. These two groups were compared in terms of perioperative results, with assessment of intraoperative and postoperative outcomes. Results: There were no significant differences in patients’ characteristics between the two groups. Operative time was longer in the TLTGS group than in the TLTG group. However, the rate of patients with postoperative complications including major complications was not different between the groups, and no patient in the TLTGS group had anastomotic leakage or pancreatic fistula. Conclusions: In the short-term, TLTGS had good postoperative outcomes and was useful and acceptable for AGC.

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.

Comparison of totally laparoscopic total gastrectomy using an endoscopic linear stapler with laparoscopic-assisted total gastrectomy using a circular stapler in patients with gastric cancer: a single-center experience

AIM To evaluate the safety and efficacy of totally laparoscopic total gastrectomy(TLTG) with esophagojejunostomy using a linear stapler compared with laparoscopic-assisted total gastrectomy(LATG) using a circular stapler in gastric cancer patients.METHODS We retrospectively reviewed 687 patients who underwent laparoscopic total gastrectomy for gastric cancer at a single institution from August 2008 to August 2014. The patients were divided into two groups according to the type of operation: 421 patients underwent TLTG and 266 underwent LATG. Clinicopathologic characteristics and surgical outcomes in the two groups were compared and analyzed.RESULTS The TLTG group had higher mean ages at the time of operation(57.78 ± 11.20 years and 55.69 ± 11.96 years,P = 0.020) and more histories of abdominal surgery(20.2% and 12.4%,P = 0.008) compared with the LATG group. Surgical outcomes such as intraoperative and postoperative transfusions,combined operations,pain scores and administration of analgesics,and complications were similar between the two groups. However,compared with the LATG group,the TLTG group required a shorter operation time(149 min vs 170 min,P < 0.001),had lower postoperative hematocrit change(3.49% vs 4.04%,P = 0.002),less intraoperative events(3.1% vs 10.2%,P < 0.001),less intraoperative anastomosis events(2.4% vs 7.1%,P = 0.003),faster postoperative recovery such as median time to first flatus(3.30 d vs 3.60 d,P < 0.001),faster median commencement of soft diet(4.30 d vs 4.60 d,P < 0.001) and shorter length of postoperative hospital stay(6.75 d vs 7.02 d,P = 0.005). CONCLUSION The intracorporeal method for reconstruction of esophagojejunostomy using a linear stapler may be considered a feasible procedure comparing with extracorporeal anastomosis using circular stapler because TLTG is simpler and more straightforward than LATG. Therefore,TLTG can be recommended as an appropriate procedure for gastric cancer.

Systematic review and meta-analysis of laparoscopy-assisted and open total gastrectomy for gastric cancer

AIM:To evaluate the safety and efficacy of laparoscopy-assisted total gastrectomy(LATG)and open total gastrectomy(OTG)for gastric cancer.METHODS:A comprehensive search of PubMed,Cochrane Library,Web of Science and BIOSIS Previews was performed to identify studies that compared LATG and OTG.The following factors were checked:operating time,blood loss,harvested lymph nodes,flatus time,hospital stay,mortality and morbidity.Data synthesis and statistical analysis were carried out using RevMan 5.1 software.RESULTS:Nine studies with 1221 participants were included(436 LATG and 785 OTG).Compared to OTG,LATG involved a longer operating time[weighted mean difference(WMD)=57.68 min,95%CI:30.48-84.88;P<0.001];less blood loss[standard mean difference(SMD)=-1.71;95%CI:-2.48--0.49;P<0.001];earlier time to flatus(WMD=-0.76 d;95%CI:-1.22--0.30;P<0.001);shorter hospital stay(WMD=-2.67d;95%CI:-3.96--1.38,P<0.001);and a decrease in medical complications(RR=0.41,95%CI:0.19-0.90,P=0.03).The number of harvested lymph nodes,mortality,surgical complications,cancer recurrence rate and long-term survival rate of patients undergoing LATG were similar to those in patients undergoing OTG.CONCLUSION:Despite a longer operation,LATG can be performed safely in experienced surgical centers with a shorter hospital stay and fewer complications than open surgery.

Laparoscopic and robot-assisted gastrectomy for gastric cancer: Current considerations

Radical gastrectomy with an adequate lymphadenectomy is the main procedure which makes it possible to cure patients with resectable gastric cancer (GC). A number of randomized controlled trials and meta-analysis provide phase III evidence that laparoscopic gastrectomy is technically safe and that it yields better short-term outcomes than conventional open gastrectomy for early-stage GC. While laparoscopic gastrectomy has become standard therapy for early-stage GC, especially in Asian countries such as Japan and South Korea, the use of minimally invasive techniques is still controversial for the treatment of more advanced tumours, principally due to existing concerns about its oncological adequacy and capacity to carry out an adequately extended lymphadenectomy. Some intrinsic drawbacks of the conventional laparoscopic technique have prevented the worldwide spread of laparoscopic gastrectomy for cancer and, despite technological advances in recent year, it remains a technically challenging procedure. The introduction of robotic surgery over the last ten years has implied a notable mutation of certain minimally invasive procedures, making it possible to overcome some limitations of the traditional laparoscopic technique. Robot-assisted gastric resection with D2 lymph node dissection has been shown to be safe and feasible in prospective and retrospective studies. However, to date there are no high quality comparative studies investigating the advantages of a robotic approach to GC over traditional laparoscopic and open gastrectomy. On the basis of the literature review here presented, robot-assisted surgery seems to fulfill oncologic criteria for D2 dissection and has a comparable oncologic outcome to traditional laparoscopic and open procedure. Robot-assisted gastrectomy was associated with the trend toward a shorter hospital stay with a comparable morbidity of conventional laparoscopic and open gastrectomy, but randomized clinical trials and longer follow-ups are needed to evaluate the possible influence of robot gastrectomy on GC patient survival.

Use of a clinical pathway in laparoscopic gastrectomy for gastric cancer

AIM: To evaluate the implementation of a clinical pathway and identify clinical factors affecting the clinical pathway for laparoscopic gastrectomy.METHODS: A standardized clinical pathway for gastric cancer(GC) patients was developed in 2001 by the GC surgery team at the Asan Medical Center. We reviewed the collected data of 4800 consecutive patients treated using the clinical pathway following laparoscopic gastrectomy with lymph node dissection for GC involving intracorporeal and extracorporeal anastomosis. The patients were treated between August 2004 and October 2013 in a single institution. To evaluate the rate of completion and risk factors affecting dropout from the clinical pathway, we used a multivariate logistic regression analysis.RESULTS: The overall completion rate of the clinical pathway for laparoscopic gastrectomy was 84.1%(n = 4038). In the comparison between groups of intracorporeal anastomosis and extracorporeal anastomosis patients, the completion rates were 8 3. 8 8 %(n = 1 7 4 0) a n d 8 4. 3 6 %(n = 2 0 7 1), respectively, showing no statistically significant difference. The main reasons for dropping out were postoperative complications(n = 463, 9.7%) and the need for patient observation(n = 299, 6.2%). Among the discharged patients treated using the clinical pathway, the number of patients who were readmitted within 30 d due to postoperative complications was 54(1.1%). In a multivariate analysis, the intraoperative events(OR = 2.558) were the most predictable risk factors for dropping out of the clinical pathway. Additionally, being male(OR = 1.459), advanced age(OR = 1.727), total gastrectomy(OR = 2.444), combined operation(OR = 1.731), and ASA score(OR = 1.889) were significant risk factors affecting the dropout rate from the clinical pathway.CONCLUSION: Laparoscopic gastrectomy appears to be a good indication for the application of a clinical pathway. For successful application, patients with risk factors should be managed carefully.

Small-volume chylous ascites after laparoscopic radical gastrectomy for gastric cancer:Results from a large population-based sample

AIM:To report the incidence and potential risk factors of small-volume chylous ascites(SVCA)following laparoscopic radical gastrectomy(LAG).METHODS:A total of 1366 consecutive gastric cancer patients who underwent LAG from January 2008 to June 2011 were enrolled in this study.We analyzed the patients based on the presence or absence of SVCA.RESULTS:SVCA was detected in 57(4.17%)patients,as determined by the small-volume drainage(range,30-100 m L/24 h)of triglyceride-rich fluid.Both univariate and multivariate analyses revealed that the total number of resected lymph nodes(LNs),No.8 or No.9 LN metastasis and N stage were independent risk factors for SVCA following LAG(P<0.05).Regarding hospital stay,there was a significant difference between the groups with and without SVCA(P<0.001).The 3-year disease-free and overall survival rates of the patients with SVCA were 47.4%and 56.1%,respectively,which were similar to those of the patients without SVCA(P>0.05).CONCLUSION:SVCA following LAG developed significantly more frequently in the patients with≥32harvested LNs,≥3 metastatic LNs,or No.8 or No.9LN metastasis.SVCA,which was successfully treated with conservative management,was associated with a prolonged hospital stay but was not associated with the prognosis.

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.

Additional laparoscopic gastrectomy after noncurative endoscopic submucosal dissection for early gastric cancer: A single-center experience

BACKGROUND The necessity of additional gastrectomy for early gastric cancer (EGC) patients who do not meet curative criteria after endoscopic submucosal dissection (ESD) is controversial. AIM To examine the clinicopathologic characteristics of patients who underwent additional laparoscopic gastrectomy after ESD and to determine the appropriate strategy for treating those after noncurative ESD. METHODS We retrospectively studied 45 patients with EGC who underwent additional laparoscopic gastrectomy after noncurative ESD from January 2013 to January 2019 at the Cancer Hospital of the Chinese Academy of Medical Sciences. We analyzed the patients’ clinicopathological data and identified the predictors of residual cancer (RC) and lymph node metastasis (LNM). RESULTS Surgical specimens showed RC in ten (22.2%) patients and LNM in five (11.1%).Multivariate analysis revealed that positive horizontal margin [odds ratio (OR)=13.393, 95% confidence interval (CI): 1.435-125, P=0.023] and neural invasion (OR=14.714, 95%CI: 1.087-199, P=0.043) were independent risk factors for RC. Undifferentiated type was an independent risk factor for LNM (OR=12.000, 95%CI: 1.197-120, P=0.035). Tumors in all patients with LNM showed submucosal invasion more than 500 μm. Postoperative complications after additional laparoscopic gastrectomy occurred in five (11.1%) patients, and no deaths occurred among patients with complications. CONCLUSION Gastrectomy is necessary not only for patients who have a positive margin after ESD, but also for cases with neural invasion, undifferentiated type, and submucosal invasion more than 500 μm. Laparoscopic gastrectomy is a safe, minimally invasive, and feasible procedure for additional surgery after noncurative ESD. However, further studies are needed to apply these results to clinical practice.