Identification of the factor affecting learning curves of laparoscopic gastrectomy through the experience at a Japanese high-volume center over the last decade.

Background: Though laparoscopic gastrectomy (LG) has become the gold standard for gastric cancer treatment according to the Japanese treatment guidelines, its learning curve remains steep. Decreasing numbers of surgeons and transitions in the work environment have changed LG training recently. We analyzed LG training over the last decade to identify factors affecting the learning curve. Study Design: Laparoscopic distal and pylorus-preserving gastrectomies conducted between 2010 and 2020 were included. We assessed learning curves based on the standard operation time (SOT) defined by analysis of covariance. Then we divided the trainees into two groups based on the length of the learning curve and examined the factors affecting the learning curve with linear regression analysis. Results: Among 2335 LGs, 960 cases treated by 27 trainees and 1301 cases treated by six attending surgeons were analyzed. The operation time was prolonged (p = 0.009) and postoperative morbidity rates were lower (p = 0.0003) for cases treated by trainees. Trainees experienced 38 (range, 9-81) cases as scopists and nine (range, 0-41) cases as first assistants to the first operator. The learning curve was approximately 30 cases. The SOT was calculated based on gender, body mass index, tumor location, reconstruction, and lymph node dissection. Trainees who had shorter learning curves had more experience (51-100 cases) with any laparoscopic surgery before LG training than the others (11-50 cases, p = 0.017). Conclusion: Sufficient experience with laparoscopic surgery before starting LG training might contribute to the efficiency of LG training and shorten the learning curve.

Diagnostic Performance of Near-Infrared Fluorescent Marking Clips in Laparoscopic Gastrectomy.

INTRODUCTION: Accurate tumor localization and resection margin acquisition are essential in gastric cancer surgery. Preoperative placement of marking clips in laparoscopic gastrectomy as well as intraoperative gastroscopy can be used for gastric cancer surgery. However, these procedures are not available at all institutions. We conducted a prospective clinical trial to investigate the diagnostic performance of near-infrared fluorescent clips (ZEOCLIP FS) in laparoscopic gastrectomy. MATERIALS AND METHODS: Patients with gastric cancer or neuroendocrine tumor in whom laparoscopic distal, pylorus-preserving, or proximal gastrectomy was planned were enrolled (n = 20) in this study. Fluorescent clips were placed proximal and/or distal to the tumor via gastroscopy on the day before surgery. During surgery, the clips were detected using a fluorescent laparoscope, and suturing was performed where fluorescence was detected. The clip locations were then confirmed via gastroscopy, and the stomach was transected. The primary endpoint was the detection rate of the marking clips using fluorescence, and the secondary endpoints were complications and distance between the clips and stitches. RESULTS: Among the 20 patients enrolled, distal and pylorus-preserving gastrectomies were performed in 18 and 2 patients, respectively. All clips were detected in 15 patients, indicating a detection rate of 75.0% (90% confidence interval: 54.4%-89.6%). Furthermore, no complications related to the clips were observed. The median distance between the clips and stitches was 5 (range, 0-10) mm. CONCLUSIONS: We report the feasibility and safety of preoperative placement and intraoperative detection of near-infrared fluorescent marking clips in laparoscopic gastrectomy.

Early gastric cancer with RhoGAP fusion is linked to frequent nodal metastasis and a part of microtubular-mucocellular histology.

INTRODUCTION: Gastric cancer with fusion genes involving the Rho GTPase-activating protein domain (RhoGAP-GC) is mainly included in the genomically stable type of The Cancer Genome Atlas classification. Clinical implications and histological characteristics of RhoGAP-GC in the early phase remain unclear. METHODS: We analyzed 878 consecutive pT1b GCs for RhoGAP and its partner genes using fluorescence in situ hybridization assay. RESULTS: RhoGAP fusion was detected in 57 (6.5%) GCs. Univariate analysis revealed that female sex, middle-lower third tumor location, advanced macroscopic type, tumor diameter > 2 cm, pT1b2, lymphatic invasion, venous invasion, negative EBER-ISH, and RhoGAP fusion were significantly associated with lymph node metastasis (LNM). Multivariate analysis presented RhoGAP fusion, lymphatic invasion, tumor diameter > 2 cm, advanced macroscopic type, venous invasion, and middle-lower third tumor location as independent risk factors for LNM. Notably, RhoGAP fusion had the highest odds ratio (3.92) for LNM among analyzed parameters (95% CI 2.12-7.27; p < 0.001). Compared to non-RhoGAP-GCs, RhoGAP-GCs were significantly frequent in younger females and showed the highest incidence of lymphatic invasion (56.2%) and LNM (49.1%) (p < 0.001). Histologically, microtubular architecture with pseudo-trabecular interconnection and small aggregations of tumor cells with a varied amount of cytoplasmic mucin, named "microtubular-mucocellular (MTMC) histology," was found in 93.0% (53 of 57) of RhoGAP-GCs in the intramucosal area. MTMC histology showed high sensitivity and negative predictive value (93.0% and 99.4%, respectively) for RhoGAP fusion, albeit positive predictive value is low (34.9%). CONCLUSION: RhoGAP-GC is linked to a characteristic MTMC histology and a high incidence of LNM.

Comparison of the survival outcomes between retrocolic and antecolic Roux-en-Y reconstruction after gastrectomy for gastric cancer.

Background: There are two methods of Roux-en-Y (RY) reconstruction after gastrectomy: the antecolic route (ACR) and retrocolic route (RCR). There is no evidence to support that the ACR achieves comparable long-term survival. Methods: This was a multi-center historical cohort study. Patients diagnosed with clinical T3/4a and any N stage who underwent open gastrectomy and R0 resection for gastric adenocarcinoma between January 2006 and December 2012 were enrolled. The primary outcome was the hazard ratio of ACR for overall survival, with adjustment for confounding factors by propensity score matching, and a Cox proportional hazards model. Results: A total of 1758 eligible patients were identified from the database. After matching, 410 patients in the ACR and RCR groups were included in the final analysis. The adjusted hazard ratio (95% CI) for ACR was 1.148 (0.870-1.492). The five-year survival rates in the ACR and RCR groups were 74.3% (69.5-78.4) and 77.3% (72.3-81.2), respectively. The short-term surgical outcomes of the two groups did not differ to a statistically significant extent. Conclusion: The route used to lift the jejunum in RY reconstruction did not affect the incidence of long-term survival or postoperative complications. The ACR and RCR are both acceptable options for RY reconstruction during gastric cancer surgery.

Equal short-term outcomes of intracorporeal mechanical gastrogastrostomy in laparoscopic pylorus-preserving gastrectomy for cT1N0 gastric cancer in the middle stomach compared with the extracorporeal hand-sewing method.

BACKGROUND: Intracorporeal mechanical gastrogastrostomy (IMG) techniques have recently been developed and their short-term safety was presented in their initial evaluation. However, whether they are comparable to extracorporeal hand-sewing gastrogastrostomy (EHG) remains unclear. The aim of the study is to establish the safety of IMG in totally laparoscopic pylorus-preserving gastrectomy (TLPPG) compared to EHG in laparoscopy-assisted pylorus-preserving gastrectomy (LAPPG). METHODS: We retrospectively analyzed the short-term outcomes of patients with middle-third early gastric cancer who underwent LAPPG or TLPPG between 2005 and 2022. The primary objective of this study was to evaluate the non-inferiority of IMG to EHG in terms of safety, with the primary endpoint being the risk difference in anastomosis-related complications (ARCs). The sample size required to achieve a statistical power of 80% for the non-inferiority test was 971 with a one-sided alpha level of 5% and non-inferiority of 5%. RESULTS: The analysis included a total of 1,021 patients who underwent LAPPG or TLPPG during the study period. Among them, 488 patients underwent EHG, while 533 underwent IMG. The incidences of ARCs were 11.3% and 11.4% in EHG and IMG, respectively. The observed difference in incidence was 0.0017 (90% confidence interval - 0.0313 to 0.0345), which statistically demonstrated the non-inferiority of IMG to EHG in the incidence of ARCs. Among other complications, the incidence of wound infection in IMG was lower than that in EHG. CONCLUSION: IMG is safe regarding ARCs compared with EHG. These results will encourage surgeons to introduce IMG for patients with early middle gastric cancer.

Clinical Impact of Polyglycolic Acid Mesh to Reduce Pancreas-Related Complications After Minimally Invasive Surgery for Gastric Cancer: A Propensity Score Matching Analysis.

PURPOSE: Prevention of pancreas-related complications after gastric cancer surgery is critical. Polyglycolic acid (PGA) mesh reduces postoperative pancreatic fistula formation following pancreatic resection. However, the clinical efficacy of PGA mesh in gastric cancer surgery has not been adequately investigated. MATERIALS AND METHODS: This retrospective study compared the short-term outcomes between two groups: patients who underwent minimally invasive R0 gastrectomy for gastric cancer with the use of a PGA mesh (PGA group) and those without the use of a PGA mesh (non-PGA group) at the Cancer Institute Hospital, Tokyo, between January 2019 and May 2023. Propensity score matching (PSM) was performed to adjust for the possible confounding factors. RESULTS: A total of 834 patients were initially included, of whom 614 (307 in each group) remained after PSM. The amylase levels in the drained abdominal fluid on postoperative days 1 and 3 were similar between the PGA and non-PGA groups. The PGA group had a significantly lower incidence of pancreas-related complications of Clavien-Dindo grade ≥2 than that in the non-PGA group (6.8% vs. 2.9%, P=0.025). In subgroup analyses, the odds ratio for pancreas-related complications appeared to be better in the PGA group than in the non-PGA group in patients with American Society of Anesthesiologists Physical Status Classification score of 2 or 3, those operated via a laparoscopic approach, and those undergoing procedures other than proximal gastrectomy. CONCLUSIONS: The use of PGA mesh significantly reduced pancreas-related complications after minimally invasive surgery for gastric cancer and might thus benefit patients at risk of such complications.

Adequate gross resection margin length ensuring pathologically complete resection in gastrectomy for gastric cancer: A systematic review and meta-analysis.

Aim: A positive resection margin (RM) is associated with poor survival after gastrectomy for gastric cancer (GC). However, the adequate RM length to avoid a positive RM remains controversial. We performed a systematic review to examine the RM length required to avoid a positive RM in gastrectomy for GC. Methods: This systematic review involved all relevant articles identified in PubMed, the Cochrane Library, Web of Science, and ClinicalTrials.gov until August 2023. The incidence of a positive RM related to the RM length and the possible incidence of a positive RM estimated from the discrepancy between the gross and pathological RM length were evaluated. The Newcastle-Ottawa Scale was used to quantify study quality. Results: Thirteen studies involving 8983 patients were analyzed. Investigation of the incidence of a positive RM in relation to the RM length showed that a proximal RM length of 6 cm guaranteed a negative RM in gastrectomy. Analyses of the possible incidence of a positive RM revealed that a negative RM would be guaranteed if the proximal RM length was 6 cm in distal gastrectomy, if the esophageal resection length was 2 cm in total gastrectomy for GC without esophageal invasion and 2.5 cm in total or proximal gastrectomy for GC with esophageal invasion or esophagogastric junction cancer, and if the distal RM length was 4 cm in proximal gastrectomy for early GC. Conclusions: The adequate RM lengths to ensure a pathologically negative RM in each type of gastrectomy for GC were herein suggested.

Impact of Perioperative Immunonutrition on Postoperative Outcomes in Patients with Upper Gastrointestinal Cancer: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

There is no consensus on the efficacy of perioperative immunonutrition in patients with upper gastrointestinal (GI) cancer surgery. We clarified the impact of perioperative immunonutrition on postoperative outcomes in patients with upper GI cancers. We searched MEDLINE (PubMed), MEDLINE (OVID), EMBASE, Cochrane Central Register of Controlled Trials, Web of Science Core Selection, and Emcare from 1981-2022 using search terms related to immunonutrition and upper GI cancer. We included randomized controlled trials. Intervention was defined as immunonutritional therapy, including arginine, n-3 omega fatty acids, or glutamine during the perioperative period. The control was defined as standard nutritional therapy. The primary outcomes were infectious complications, defined as events with a Clavien-Dindo classification grade ≥ II that occurred within 30 days after surgery. After screening, 23 studies were included in the qualitative synthesis and in the quantitative synthesis. The meta-analysis showed that immunonutrition reduced infectious complications (relative risk ratio: 0.72; 95% confidence interval: 0.57-0.92; certainty of evidence: Moderate) compared with standard nutritional therapy. In conclusion, nutritional intervention with perioperative immunonutrition in patients with upper GI cancers significantly reduced infectious complications. The effect of immunonutrition for upper GI cancers in reducing the risk of infectious complications was about 30%.

Perioperative or neoadjuvant chemotherapy for locally advanced gastric or gastroesophageal junction cancer: from independent evidence in the West, the East, and Japan to global collaboration.

The survival outcome of patients with locally advanced gastric or gastroesophageal junction (G/GEJ) cancer remains unsatisfactory, and improvements in survival and recurrence remain urgent issues for clinicians worldwide. Prior to the 2000s, locally advanced G/GEJ was a different disease between the West and the East regarding diagnosis, surgery, and prognosis. However, recent advances in medical oncology have set the stage for harmonization. Herein, this review highlights clinical trials of perioperative or neoadjuvant chemotherapy conducted during the past two decades to provide insights into future directions. We focused on pivotal clinical trials of perioperative or neoadjuvant chemotherapy for patients with locally advanced G/GEJ cancer. We paid special attention to the indication and oncological outcomes of perioperative or neoadjuvant chemotherapy. The attempts to investigate the optimal treatment strategy for locally advanced G/GEJ cancer over the past 20 years have resulted in a global consensus on the necessity of perioperative or neoadjuvant chemotherapy, although there have been different circumstances regarding treatment for G/GEJ cancer among the West, the East other than Japan, and Japan. Two randomized global phase III trials, the KEYNOTE-585 and MATTHERHORN, were successfully accomplished for a common indication. Furthermore, perioperative immunotherapy suggested a new indication with molecular biomarkers such as microsatellite status or PD-L1 status beyond the conventional tumor-lymph node-metastasis (TNM) staging system. Global studies provide the stage for discussing the future optimal indication of neoadjuvant chemotherapy, opening the door for future global collaborations to better treat patients with locally advanced G/GEJ cancer.

Impact of Olfactory Change on Postoperative Body Weight Loss in Patients with Gastric Cancer after Gastrectomy.

Patients undergoing gastrectomy for gastric cancer may experience alterations in olfaction, yet the association between olfactory changes and postoperative weight loss remains uncertain. This study aimed to elucidate the relationship between olfactory changes and postoperative weight loss in patients with gastric cancer. Patients who underwent radical gastrectomy for gastric cancer between February 2022 and August 2022 were included in the study. Those experiencing a higher Visual Analog Scale (VAS) score postoperatively compared to preoperatively were deemed to have undergone olfactory changes. Postoperative weight loss was determined using the 75th percentile as a cutoff value, designating patients surpassing this threshold as experiencing significant weight loss. Multivariate logistic regression analysis was employed to identify risk factors for postoperative weight loss, with statistical significance set at p < 0.05. Out of 58 patients, 10 (17.2%) exhibited olfactory changes. The rate of postoperative weight loss at one month was markedly higher in the group with olfactory changes compared to those without (9.6% versus 6.2%, respectively; p = 0.002). In addition, the group experiencing olfactory changes demonstrated significantly lower energy intake compared to the group without such changes (1050 kcal versus 1250 kcal, respectively; p = 0.029). Logistic regression analysis revealed olfactory changes as an independent risk factor for significant weight loss at one month postoperatively (odds ratio: 7.64, 95% confidence interval: 1.09-71.85, p = 0.048). In conclusion, olfactory changes emerged as an independent risk factor for postoperative weight loss at one month in patients with gastric cancer following gastrectomy.

Impact of preoperative prealbumin levels on long-term prognosis in patients with gastric cancer after gastrectomy: a retrospective cohort study.

BACKGROUND: The relationship between preoperative prealbumin levels and long-term prognoses in patients with gastric cancer after gastrectomy has not been fully investigated. This study clarified the effect of preoperative prealbumin levels on the long-term prognosis of patients with gastric cancer after gastrectomy. METHODS: This retrospective cohort study included consecutive patients who underwent radical gastrectomy for primary pStage I-III gastric cancer and whose preoperative prealbumin levels were measured between May 2006 and March 2017. Participants were categorized according to their preoperative prealbumin levels into high (≥22 mg/dL), moderate (15-22 mg/dL), and low (<15 mg/dL) groups. The overall survival (OS) in the three groups was compared using the log-rank test, and prognostic factors were identified using Cox proportional hazards regression analysis. RESULTS: The median follow-up duration was 66 months. Of 4732 patients, 3649 (77.2%) were classified as high, 925 (19.6%) as moderate, and 158 (3.3%) as low. Lower prealbumin levels were associated with poorer prognoses (P < 0.001). Multivariate analysis showed that prealbumin levels of 15-22 mg/dL [hazard ratio (HR): 1.576, 95% confidence interval (CI): 1.353-1.835, P < 0.001] and <15 mg/dL (HR: 1.769, 95% CI: 1.376-2.276, P < 0.001) were independent poor prognostic factors for OS. When analyzed according to the cause of death, prealbumin levels were associated with other-cause survival, but not cancer-specific survival. CONCLUSIONS: Preoperative prealbumin levels correlated with OS in patients with gastric cancer after gastrectomy; the lower the prealbumin level, the worse is the prognosis. Prealbumin levels may be associated with other-cause survival.

Impact of treatment guidelines and pivotal clinical trial results on a surgeon's decision regarding treatment for gastric cancer: a retrospective cohort study using the National Clinical Database.

PURPOSES: The present study evaluated the impact of clinical guidelines for gastric cancer surgery on surgeons' choice of procedure in real-world practice. We focused on the 2014 guideline revision recommending laparoscopic surgery and the evidence concerning splenectomy for prophylactic lymphadenectomy reported in 2015 using the National Clinical Database, which is the most comprehensive database in Japan. METHODS: We investigated the monthly percentages of laparoscopic distal gastrectomies performed for stage I gastric cancer (LDG%) and splenectomies performed during total gastrectomy for advanced cancer (TGS%) between 2014 and 2017. We evaluated the descriptive statistics of the time-series changes in the LDG%, TGS%, and annual trends of outcomes. RESULTS: In total, 124,787 patients were enrolled. The mean LDG% and TGS% were 69.8% and 9.2%, respectively. The LDG% and TGS% were 66.4% and 16.7%, respectively, in January 2014 and 73.1% and 5.9%, respectively, in December 2017. LDG% consistently increased, and TGS% showed a consistent downward trend throughout the observation period. There was no significant change in this trend after the publication of the guideline recommendations or clinical trial results. CONCLUSION: No significant changes in surgical procedures were observed after publication of the guidelines or results of clinical trials.

Risk factors for early recurrence after radical gastrectomy followed by adjuvant chemotherapy for stage II or III gastric cancer: a multicenter, retrospective study.

BACKGROUND: Radical gastrectomy followed by adjuvant chemotherapy is the standard treatment for stage II or III gastric cancer in Asian countries. Early recurrence during or after adjuvant chemotherapy is associated with poor prognosis; however, risk factors for early recurrence remain unclear. METHODS: In this multicenter, retrospective cohort study including six institutions, we evaluated the clinicopathological factors of 553 patients with gastric cancer undergoing gastrectomy followed by adjuvant chemotherapy between 2012 and 2016. Patients were divided into the following groups: early recurrence (recurrence during adjuvant chemotherapy or within 6 months after adjuvant chemotherapy completion) and non-early recurrence, which was further divided into late recurrence and no recurrence. Early-recurrence risk factors were investigated using multivariate Cox proportional hazard model. The chronological changes in the recurrence hazard were also examined for each factor. RESULTS: Early recurrence and late recurrence occurred in 83 (15.0%) and 73 (13.2%) patients, respectively. Based on the Cox proportional hazards model, a postoperative serum carcinoembryonic antigen level of ≥5 ng/mL (hazard ratio: 2.220, 95% confidence interval: 1.089-4.526) and a neutrophil-to-lymphocyte ratio of >1.8 (hazard ratio: 2.408, 95% confidence interval: 1.479-3.92) were identified as independent risk factors of early recurrence, but not late recurrence. The recurrence hazard ratios for neutrophil-to-lymphocyte ratio significantly decreased over time (P < 0.001) and carcinoembryonic antigen also had the same tendency (P = 0.08). CONCLUSIONS: A carcinoembryonic antigen level of ≥5 ng/mL and a neutrophil-to-lymphocyte ratio of >1.8 are predictors of early recurrence after radical gastrectomy and adjuvant chemotherapy for stage II or III gastric cancer.

Short-term outcomes of preoperative chemotherapy with docetaxel, oxaliplatin, and S-1 for gastric cancer with extensive lymph node metastasis (JCOG1704).

BACKGROUND: The prognosis for marginally resectable gastric cancer with extensive lymph node metastasis (ELM) remains unfavorable, even after R0 resection. To assess the safety and efficacy of preoperative docetaxel, oxaliplatin, and S-1 (DOS), we conducted a multicenter phase II trial. METHODS: Eligibility criteria included histologically proven HER2-negative gastric adenocarcinoma with bulky nodal (bulky N) involvement around major branched arteries or para-aortic node (PAN) metastases. Patients received three cycles of docetaxel (40 mg/m2, day 1), oxaliplatin (100 mg/m2, day 1), and S-1 (80-120 mg/body, days 1-14), followed by gastrectomy with D2 plus PAN dissection. Subsequently, patients underwent postoperative chemotherapy with S-1 for 1 year. The primary endpoint was major (grade ≥ 2a) pathological response rate (pRR) according to the Japanese Classification of Gastric Carcinoma criteria. RESULTS: Between October 2018 and March 2022, 47 patients (bulky N, 20; PAN, 17; both, 10) were enrolled in the trial. One patient was ineligible. Another declined any protocol treatments before initiation. Among the 45 eligible patients who initiated DOS chemotherapy, 44 (98%) completed 3 cycles and 42 (93%) underwent R0 resection. Major pRR and pathological complete response rates among the 46 eligible patients, including the patient who declined treatment, were 57% (26/46) and 24% (11/46), respectively. Common grade 3 or 4 toxicities were neutropenia (24%), anorexia (16%), febrile neutropenia (9%), and diarrhea (9%). No treatment-related deaths occurred. CONCLUSIONS: Preoperative chemotherapy with DOS yielded favorable pathological responses with an acceptable toxicity profile. This multimodal approach is highly promising for treating gastric cancer with ELM.

5-year follow-up results of a JCOG1104 (OPAS-1) phase III non-inferiority trial to compare 4 courses and 8 courses of S-1 adjuvant chemotherapy for pathological stage II gastric cancer.

BACKGROUND: Postoperative adjuvant chemotherapy with S-1 for 1 year (corresponding to eight courses) is the standard treatment for pathological stage II gastric cancer. The phase III trial (JCOG1104) investigating the non-inferiority of four courses of S-1 to eight courses was terminated due to futility at the first interim analysis. To confirm the primary results, we reported the results after a 5-years follow-up in JCOG1104. METHODS: Patients histologically diagnosed with stage II gastric cancer after radical gastrectomy were randomly assigned to receive S-1 for eight or four courses. In detail, 80 mg/m2/day S-1 was administered for 4 weeks followed by a 2-week rest as a single course. RESULTS: Between February 16, 2012, and March 19, 2017, 590 patients were enrolled and randomly assigned to 8-course (295 patients) and 4-course (295 patients) regimens. After a 5-years follow-up, the relapse-free survival at 3 years was 92.2% for the 8-course arm and 90.1% for the 4-course arm, and that at 5 years was 87.7% for the 8-course arm and 85.6% for the 4-course arm (hazard ratio 1.265, 95% CI 0.846-1.892). The overall survival at 3 years was 94.9% for the 8-course arm, 93.2% for the 4-course arm, and that at 5 years was 89.7% for the 8-course arm, and 88.6% for the 4-course arm (HR 1.121, 95% CI 0.719-1.749). CONCLUSIONS: The survival of the four-course arm was slightly but consistently inferior to that of the eight-course arm. Eight-course S-1 should thus remain the standard adjuvant chemotherapy for pathological stage II gastric cancer.

Long-term impact of sarcopenia in older patients undergoing gastrectomy for gastric cancer: a systematic review and meta-analysis.

Background: Sarcopenia is an inevitable problem in older patients. After gastrectomy, patients often have an inadequate dietary intake and easily fall into sarcopenia. However, the impact of preoperative sarcopenia on long-term outcomes after gastrectomy has not been analyzed. Methods: A systematic review was conducted for all relevant articles identified on PubMed, the Cochrane Library, Web of Science, and ClinicalTrials.gov until April 2023. Adjusted hazard ratios (HRs) and odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using the fixed or random effects model according to the heterogeneity. The Newcastle-Ottawa Scale was used to quantify study quality. Results: Seven studies involving 1,831 patients aged ≥65 years who underwent gastrectomy for gastric cancer were analyzed. Four hundred twelve patients (22.5%) were diagnosed with sarcopenia. The analysis showed that preoperative sarcopenia was significantly associated with poor overall survival (OS) (HR =1.93; 95% CI:1.60-2.34; P<0.001). Two of the included studies also showed that preoperative sarcopenia was significantly correlated with disease-related survival: one with disease-specific survival (DSS) (HR =4.00; 95% CI: 1.20-13.3, P=0.024) and the other with non-cancer specific survival (HR =3.27; 95% CI: 1.61-6.67; P=0.001). Furthermore, sarcopenic patients experienced more severe complications than non-sarcopenic patients (OR =1.80; 95% CI: 1.10-2.95; P=0.019). Conclusions: This meta-analysis suggested that preoperative sarcopenia is useful as a prognostic factor of impaired OS in older patients after gastrectomy. Preoperative evaluation and intervention for skeletal muscle loss should be considered. Further studies of sarcopenic impact on disease-related survival are required.

Randomized controlled phase III trial to investigate superiority of robot-assisted gastrectomy over laparoscopic gastrectomy for clinical stage T1-4aN0-3 gastric cancer patients (JCOG1907, MONA LISA study): a study protocol.

BACKGROUND: Laparoscopic gastrectomy (LG) is considered a standard treatment for clinical stage I gastric cancer. Nevertheless, LG has some drawbacks, such as motion restriction and difficulties in spatial perception. Robot-assisted gastrectomy (RG) overcomes these drawbacks by using articulated forceps, tremor-filtering capability, and high-resolution three-dimensional imaging, and it is expected to enable more precise and safer procedures than LG for gastric cancer. However, robust evidence based on a large-scale randomized study is lacking. METHODS: We are performing a randomized controlled phase III study to investigate the superiority of RG over LG for clinical T1-2N0-2 gastric cancer in terms of safety. In total, 1,040 patients are planned to be enrolled from 46 Japanese institutions over 5 years. The primary endpoint is the incidence of postoperative intra-abdominal infectious complications, including anastomotic leakage, pancreatic fistula, and intra-abdominal abscess of Clavien-Dindo (CD) grade ≥ II. The secondary endpoints are the incidence of all CD grade ≥ II and ≥ IIIA postoperative complications, the incidence of CD grade ≥ IIIA postoperative intra-abdominal infectious complications, relapse-free survival, overall survival, the proportion of RG completion, the proportion of LG completion, the proportion of conversion to open surgery, the proportion of operation-related death, and short-term surgical outcomes. The Japan Clinical Oncology Group Protocol Review Committee approved this study protocol in January 2020. Approval from the institutional review board was obtained before starting patient enrollment in each institution. Patient enrollment began in March 2020. We revised the protocol to expand the eligibility criteria to T1-4aN0-3 in July 2022 based on the results of randomized trials of LG demonstrating non-inferiority of LG to open surgery for survival outcomes in advanced gastric cancer. DISCUSSION: This is the first multicenter randomized controlled trial to confirm the superiority of RG over LG in terms of safety. This study will demonstrate whether RG is superior for gastric cancer. TRIAL REGISTRATION: The protocol of JCOG1907 was registered in the UMIN Clinical Trials Registry as UMIN000039825 ( http://www.umin.ac.jp/ctr/index.htm ). Date of Registration: March 16, 2020. Date of First Participant Enrollment: April 1, 2020.

Robotic Splenic Vessels Preserving Distal Pancreatectomy in a Post-Distal Gastrectomy Patient.

BACKGROUND: The optimal procedure during distal pancreatectomy (DP) for patients who have undergone distal gastrectomy (DG) remains unclear. Several papers on remnant gastric ischemia have reported that the preserved splenic vessels are essential for the proximal remnant stomach.1-4 We evaluated the outcomes of DP for post-DG patients in our hospital and introduced robotic splenic vessels preserving DP (R-SPDP). METHODS: Postoperative short-term outcomes of DP for post-DG patients during 2014 and 2021 were evaluated. Next, R-SPDP was performed for a post-DG patient with the intention of preserving the remnant stomach safely. The double bipolar method was used to dissect the adhesions around the splenic vessels.5,6 The splenic artery was clamped at the root side to prevent bleeding.7 All short gastric arteries and veins, which were the main feeders of the remnant stomach, were preserved and resection was completed. After resection, the indocyanine green (ICG) fluorescence angiography confirmed blood flow in the short gastric arteries and veins and good return blood flow to the splenic vein.8 RESULTS: Of four patients (50.0%, of 8 DP patients) in whom the remnant stomach was preserved, one conventional DP case had poor ICG perfusion and presented with remnant stomach ischemia postoperatively. The R-SPDP case with good ICG perfusion had a total operation time of 371 minutes and intraoperative blood loss of 10 mL. The oral diet was started on postoperative Day 3, and the postoperative course was uneventful. CONCLUSIONS: R-SPDP can be a good option for post-DG patients to preserve the remnant stomach safely.

Optimal resection of gastric bronchogenic cysts based on anatomical continuity with adherent gastric muscular layer: A case report.

BACKGROUND: Bronchogenic cysts are congenital lesions requiring radical resection because of malignant potential. However, a method for the optimal resection of these cysts has not been completely elucidated. CASE SUMMARY: Herein, we presented three patients with bronchogenic cysts that were located adjacent to the gastric wall and resected laparoscopically. The cysts were detected incidentally with no symptoms and the preoperative diagnosis was challenging to obtain via radiological examinations. Based on laparoscopic findings, the cyst was attached firmly to the gastric wall and the boundary between the gastric and cyst walls was difficult to identify. Consequently, resection of cysts alone caused cystic wall injury in Patient 1. Meanwhile, the cyst was resected completely along with a part of the gastric wall in Patient 2. Histopathological examination revealed the final diagnosis of bronchogenic cyst and revealed that the cyst wall shared the muscular layer with the gastric wall in Patients 1 and 2. In Patient 3, the cyst was located adjacent to the gastric wall but histopathologically originated from diaphragm rather than stomach. All the patients were free from recurrence. CONCLUSION: The findings of this study state that a safe and complete resection of bronchogenic cysts required the adherent gastric muscular layer or full-thickness dissection, if bronchogenic cysts are suspected via pre- and/or intraoperative findings.