Totally laparoscopic versus laparoscopy-assisted distal gastrectomy: the KLASS-07, a randomized controlled trial.

BACKGROUNDS: Strong evidence is lacking as no confirmatory randomized controlled trials (RCTs) have compared the efficacy of totally laparoscopic distal gastrectomy (TLDG) with laparoscopy-assisted distal gastrectomy (LADG). We performed an RCT to confirm if TLDG is different from LADG. METHODS: The XXXXX trial is a multicentre, open-label, parallel-group, phase III, RCT of 442 patients with clinical stage I gastric cancer. Patients were enrolled from 21 cancer care centers in South Korea between January 2018 and September 2020 and randomized to undergo TLDG or LADG using blocked randomization with a 1:1 allocation ratio, stratified by the participating investigators. Patients were treated through R0 resections by TLDG or LADG as the full analysis set of the XXXXX trial. The primary endpoint was morbidity within postoperative day 30, and the secondary endpoint was QoL for 1 year. This trial is registered at ClinicalTrials.gov (NCT XXXXXXXX). RESULTS: 442 patients were randomized (222 to TLDG, 220 to LADG), and 422 patients were included in the pure analysis (213 and 209, respectively). The overall complication rate did not differ between the two groups (TLDG vs. LADG: 12.2% vs. 17.2%). However, TLDG provided less postoperative ileus and pulmonary complications than LADG (0.9% vs. 5.7%, P=0.006; and 0.5% vs. 4.3%, P=0.035, respectively). The QoL was better after TLDG than after LADG regarding emotional functioning at 6 months, pain at 3 months, anxiety at 3 and 6 months, and body image at 3 and 6 months (all P<0.05). However, these QoL differences were resolved at 1 year. CONCLUSIONS: The XXXXX trial confirmed that TLDG is not different from LADG in terms of postoperative complication but has advantages to reduce ileus and pulmonary complications. TLDG can be a good option to offer better QoL in terms of pain, body image, emotion, and anxiety at 3-6 months.

Survey of Information Acquisition and Satisfaction after Bariatric Surgery at a Tertiary Hospital in Korea.

Background: To determine how patients who underwent bariatric surgery at a tertiary hospital in Korea first considered and then decided to get the surgery and identify information gaps among patients and healthcare professionals. Methods: This study included 21 patients who underwent bariatric surgery to treat morbid obesity (body mass index [BMI] ≥35 or ≥30 kg/m2 together with obesity-related comorbidities) between August 2020 and February 2022. A telephone interview was conducted with the patients after at least 6 months had elapsed since the surgery. We asked how the patients decided to undergo bariatric surgery. We also inquired about their satisfaction with and concerns about the surgery. Results: Seventy-one percent of the patients were introduced to bariatric surgery following a recommendation from healthcare professionals, acquaintances, or social media. Most of the patients (52%) decided to undergo bariatric surgery based on recommendations from healthcare professionals in non-surgical departments. Satisfaction with the information provided differed among the patients. Post-surgical concerns were related to postoperative symptoms, weight regain, and psychological illness. Conclusion: Efforts are needed to raise awareness about bariatric surgery among healthcare professionals and the public. Tailored pre- and postoperative consultation may improve quality of life after bariatric surgery.

Reappraisal of optimal reconstruction after distal gastrectomy - a study based on the KLASS-07 database.

BACKGROUNDS: This study aimed to compare the incidence of bile reflux, quality of life (QoL), and nutritional status among Billroth II (BII), Billroth II with Braun anastomosis (BII-B), and Roux-en-Y (RY) reconstruction after laparoscopic distal gastrectomy (LDG). MATERIALS AND METHODS: We reviewed the prospective data of 397 patients from a multicentre database who underwent LDG for gastric cancer between 2018 and 2020 at 20 tertiary teaching hospitals in Korea. Postoperative endoscopic findings, QoL surveys using the European Organization for Research and Treatment of Cancer questionnaire (C30 and STO22), and nutritional and surgical outcomes were compared among groups. RESULTS: In endoscopic findings, bile reflux was the lowest in the RY group ( n =67), followed by the BII-B ( n =183) and BII groups ( n =147) at 1 year (3.0 vs. 67.8 vs. 84.4%, all P <0.05). The anti-reflux capability of BII-B was statistically better than that of BII, but not as perfect as that of RY. From the perspective of QoL, BII-B was not inferior to RY, but better than BII reconstruction in causing fewer STO22 reflux symptoms at 6 and 12 months. However, only RY caused fewer C30 nausea symptoms than BII at 6 and 12 months, but not BII-B. Nutritional status and morbidities were similar among the three groups, and the operative time did not differ between the BII-B and RY groups. CONCLUSIONS: BII-B cannot substitute for RY in preventing bile reflux, shortening the operative time, or reducing morbidities. Regarding short-term QoL, BII-B was sufficient to reduce STO22 reflux symptoms but failed to reduce C30 nausea symptoms postoperatively.

Does total omentectomy prevent peritoneal seeding for advanced gastric cancer with serosal invasion?

BACKGROUND: Radical gastrectomy is composed of gastrectomy, lymph node dissection, and omentectomy. Total omentectomy (TO) is expected to reduce the incidence of peritoneal recurrence. We aimed to investigate the necessity of TO for advanced gastric cancer (AGC) with serosal invasion. METHODS: We retrospectively reviewed 310 patients who underwent radical gastrectomy with TO and 93 patients who underwent partial omentectomy (PO) for gastric cancer with serosal invasion between August, 2005 and December, 2017. Finally, 91 patients in the PO group and 91 in the TO group were enrolled based on a 1:1 propensity-score matching analysis. We evaluated surgical and oncological outcomes, including 5-year overall and recurrence-free survival rates. RESULTS: There was no statistically significant difference between the two groups in postoperative complications. Recurrence sites showed similar patterns in both groups, including peritoneal recurrence (PO vs. TO, 18.7% vs. 28.6%; p = 0.188). Five-year overall survival was better in the PO group (p = 0.018), while 5-year recurrence-free survival was similar in both groups (p = 0.066). CONCLUSION: TO might not be an essential part of preventing peritoneal recurrence for AGC with serosal invasion. PO could be considered a radical gastrectomy for T4a gastric cancer.

Analysis of risk factors affecting long-term survival in elderly patients with advanced gastric cancer.

BACKGROUND: Factors predicting postoperative complications after gastrectomy for elderly patients with gastric cancer have been analyzed in several previous studies. However, there is limited research available on risk factors related to long-term survival. AIMS: This study aimed to analyze factors affecting long-term survival after curative gastrectomy in elderly patients with advanced gastric cancer. METHODS: This study included patients aged > 75 years with histologically confirmed advanced gastric cancer stage II or greater. Before analysis, risk factors were categorized into four groups: baseline characteristics, underlying diseases, surgical and pathologic factors, and nutritional factors. RESULTS: The mean follow-up duration was 71.0 months. The 5-year overall survival and disease-specific survival rates were 51.5% and 58.3%, respectively. Kaplan-Meier curves showed that patients who were female and overweight had significantly longer survival rates than those who were male and underweight. Elderly patients who underwent a total gastrectomy had poorer survival rates than those who underwent a distal gastrectomy. Multivariate analysis demonstrated that tumor stage, extent of gastrectomy, overweight status and overall complication were independent risk factors for overall survival. DISCUSSION: Our study show that the overweight patients, the extent of gastrectomy, tumor stage and overall complications are significant risk factors affecting long-term survival. CONCLUSIONS: Therefore, surgeons may be cautious in performing total gastrectomy in elderly gastric cancer patients. Additionally, it is important to focus on improving nutritional status and mitigating overall complications.

Complication After Gastrectomy for Gastric Cancer According to Hospital Volume: Based on Korean Gastric Cancer Association-Led Nationwide Survey Data.

PURPOSE: This study aimed to analyze the incidence and risk factors of complications following gastric cancer surgery in Korea and to compare the correlation between hospital complications based on the annual number of gastrectomies performed. MATERIALS AND METHODS: A retrospective analysis was conducted using data from 12,244 patients from 64 Korean institutions. Complications were classified using the Clavien-Dindo classification (CDC). Univariate and multivariate analyses were performed to identify the risk factors for severe complications. RESULTS: Postoperative complications occurred in 14% of the patients, severe complications (CDC IIIa or higher) in 4.9%, and postoperative death in 0.2%. The study found that age, stage, American Society of Anesthesiologists (ASA) score, Eastern Cooperative Oncology Group (ECOG) score, hospital stay, approach methods, and extent of gastric resection showed statistically significant differences depending on hospital volumes (P<0.05). In the univariate analysis, patient age, comorbidity, ASA score, ECOG score, approach methods, extent of gastric resection, tumor-node-metastasis (TNM) stage, and hospital volume were significant risk factors for severe complications. However, only age, sex, ASA score, ECOG score, extent of gastric resection, and TNM stage were statistically significant in the multivariate analysis (P<0.05). Hospital volume was not a significant risk factor in the multivariate analysis (P=0.152). CONCLUSIONS: Hospital volume was not a significant risk factor for complications after gastric cancer surgery. The differences in the frequencies of complications based on hospital volumes may be attributed to larger hospitals treating patients with younger age, lower ASA scores, better general conditions, and earlier TNM stages.

Comparison of Laparoscopic and Open Gastrectomy for Patients With Gastric Cancer Treated With Neoadjuvant Chemotherapy: A Multicenter Retrospective Study Based on the Korean Gastric Cancer Association Nationwide Survey.

PURPOSE: Despite scientific evidence regarding laparoscopic gastrectomy (LG) for advanced gastric cancer treatment, its application in patients receiving neoadjuvant chemotherapy remains uncertain. MATERIALS AND METHODS: We used the 2019 Korean Gastric Cancer Association nationwide survey database to extract data from 489 patients with primary gastric cancer who received neoadjuvant chemotherapy. After propensity score matching analysis, we compared the surgical outcomes of 97 patients who underwent LG and 97 patients who underwent open gastrectomy (OG). We investigated the risk factors for postoperative complications using multivariate analysis. RESULTS: The operative time was significantly shorter in the OG group. Patients in the LG group had significantly less blood loss than those in the OG group. Hospital stay and overall postoperative complications were similar between the two groups. The incidence of Clavien-Dindo grade ≥3 complications in the LG group was comparable with that in the OG group (1.03% vs. 4.12%, P=0.215). No statistically significant difference was observed in the number of harvested lymph nodes between the two groups (38.60 vs. 35.79, P=0.182). Multivariate analysis identified body mass index (odds ratio [OR], 1.824; 95% confidence interval [CI], 1.029-3.234; P=0.040) and extent of resection (OR, 3.154; 95% CI, 1.084-9.174; P=0.035) as independent risk factors for overall postoperative complications. CONCLUSIONS: Using a large nationwide multicenter survey database, we demonstrated that LG and OG had comparable short-term outcomes in patients with gastric cancer who received neoadjuvant chemotherapy.

Factors Associated With Loss to Follow-up After Laparoscopic Sleeve Gastrectomy: A Single-Center Retrospective Study.

Purpose: After bariatric surgery, postoperative follow-up is important for evaluating long-term outcomes, such as successful weight loss and improvement of metabolic parameters. However, many patients are lost to follow-up within 1 year. This study aimed to identify the follow-up rate of bariatric surgery and predictive factors of loss to follow-up (LTF). Materials and Methods: We retrospectively reviewed the data of 61 patients receiving bariatric surgery for obesity (laparoscopic sleeve gastrectomy; LSG group) and 872 for early gastric cancer (EGC group) from November 2018 to July 2020 in a single center. After 1:1 matching, we compared the LTF rate. In the LSG group, we analyzed the factors associated with LTF. Additionally, we collected weight data in the LTF group by a telephone survey. Results: By 1:1 matching, 47 patients for each group were identified. The LTF rates of the LSG and EGC groups were 34.0% (16 patients) and 2.1% (one patient), respectively (P=0.0003). In the LSG group, the LTF rate increased over the postoperative month. Of the patients, 29.5% who missed a scheduled appointment within one year comprised the LTF group. In the analysis, no significant factors associated with LTF were identified. The only factor with borderline significance was dyslipidemia with medication (P=0.094). Conclusion: The LSG group demonstrated a high LTF rate, although adherence to follow-up was closely related to postoperative outcomes. Therefore, educating patients on the significance of follow-up is important. Particularly, continuous efforts to identify the associated factors and develop a multidisciplinary management protocol after bariatric surgery are necessary.

Safety evaluation of curative gastrectomy for gastric cancer patients who underwent liver transplantation: a comparative study with conventional gastrectomy for gastric cancer patients.

BACKGROUND: We aimed to examine the technical and oncological safety of curative gastrectomy for gastric cancer patients who underwent liver transplantation. METHODS: In this study, we compared the surgical and oncological outcomes of two groups. The first group consisted of 32 consecutive patients who underwent curative gastrectomy for gastric cancer after liver transplantation (LT), while the other group consisted of 127 patients who underwent conventional gastrectomy (CG). In addition, a subgroup analysis was performed to evaluate the impact of the background differences and the surgical outcomes on the involvement of a specialized liver transplant surgery team. RESULTS: The mean operative time was significantly longer in the LT group (p < 0.05). Furthermore, there were more frequent cases of postoperative transfusion in the LT group compared to the CG group (p < 0.05). However, there were no significant differences in the overall complications between the groups (25.00 vs 23.62%, p = 0.874). The 5-year overall survival rates of the LT and CG groups were 76.7% and 90.1%, respectively (p < 0.05). The results of the subgroup analysis demonstrated no statistically significant difference in various early surgical outcomes, such as time to transfusion during surgery, first flatus, time to first soft diet, postoperative complications, hospital stay after surgery, and the number of harvested lymph nodes except for operation time. CONCLUSIONS: Despite one's medical history of undergoing LT, our study demonstrated that curative gastrectomy could be a surgically safe treatment for gastric cancer. However, further study should be conducted to identify the reason gastric cancer patients who underwent liver transplant surgery have lower overall survival rate.

Novel temperature-responsive hydrogel injected to the incision site for postoperative pain relief in laparoscopic abdominal surgery: a single-blind, randomized, pivotal clinical trial.

BACKGROUND: A temperature-responsive hydrogel (PF-72; TGel Bio, Inc., Ltd, Seoul, Korea), developed as a sustained drug delivery device, can be mixed with ropivacaine to reduce pain in the incision area. The hydrogel is soluble at low temperatures (2-8 °C) and is converted into a gel at high temperatures (> 30 °C). We aimed to evaluate whether the administration of ropivacaine using PF-72 at incision sites reduces pain until 72 h postoperatively in patients undergoing laparoscopic stomach or colorectal surgery. METHODS: Patients were randomly assigned to the control group (0.75% ropivacaine) or PF-72 group (PF-72 mixed with 0.75% ropivacaine). Before surgical incision closure, 0.75% ropivacaine or PF-72 mixed with 0.75% ropivacaine was injected into the subcutaneous fat and muscle of all incisions. Postoperative pain was evaluated by the Numerical Rating Scale (NRS, 0 = no pain, 10 = most severe pain) for wound pain at 3, 6, 24, 48, and 72 h after the end of surgery. RESULTS: Ninety-nine patients (control, n = 51; PF-72, n = 48) were included in the analysis. The areas under the curve of NRS for wound pain until 72 h in the control group and the PF-72 group were 188.7 ± 46.1 and 135.3 ± 49.9 h, respectively (P < 0.001). The frequency of the administration of rescue analgesics in the general ward was similar between the two groups. CONCLUSION: PF-72 mixed with 0.75% ropivacaine reduced postoperative pain until 72 h in patients undergoing laparoscopic surgery. Although the study population was not large enough for safety evaluation, no adverse events associated with PF-72 were observed.

Comparing surgical and oncologic outcomes between laparoscopic gastrectomy and open gastrectomy in advanced gastric cancer with serosal invasion: A retrospective study with propensity score matching.

PURPOSE: Laparoscopic gastrectomy (LG) has gradually increased for treating advanced gastric cancer (AGC). However, there is a lack of evidence on oncologic safety for AGC, especially with serosal invasion. This study evaluates the surgical and oncologic outcomes between laparoscopic and open gastrectomy (OG) for gastric cancer with serosal invasion. METHODS: We retrospectively reviewed 256 patients who underwent OG and 147 patients who underwent LG for gastric cancer with serosal invasion between August 2005 and December 2017. Finally, 124 patients in the LG group and 124 in the OG group were enrolled according to one-to-one propensity score matching (PSM) analysis. We evaluated surgical and oncological outcomes, including overall survival (OS) and recurrence-free survival (RFS). RESULTS: There were no statistical differences in hospital stay and major complications between the two groups. The retrieved lymph nodes of the LG group were similar to those of OG (40 ± 16.23 vs. 38 ± 14.42, p = 0.306), and it showed a similar operation time compared with the other (164 ± 43.86 vs. 156 ± 37.66, p = 0.063). There was no statistical difference in OS (p = 0.761) and RFS (p = 0.121) for survival analysis between the two groups. CONCLUSION: LG for gastric cancer with serosal invasion is feasible and could be considered as a standard treatment.

Reevaluation of the expanded indications in undifferentiated early gastric cancer for endoscopic submucosal dissection.

BACKGROUND: Although the criteria for the indication of endoscopic submucosal dissection (ESD) for undifferentiated early gastric cancer (UD-EGC) have been recently proposed, accumulating reports on the non-negligible rate of lymph node metastasis (LNM) after indicated ESD raise questions on the reliability of the current criteria. AIM: To investigate the prevalence and risk factors of LNM in UD-EGC cases meeting the expanded indication for ESD. METHODS: We retrospectively reviewed 4780 UD-EGC cases that underwent surgical resection between January 2008 and February 2019 at Asan Medical Center, a tertiary university hospital in Korea. To identify the risk factors of LNM of UD-EGC meeting the expanded criteria for ESD, we performed a case-control study by matching the cases with LNM to those without at a ratio of 1:4. We reviewed the clinical, endoscopic, and histologic features of the cases to identify features with a significant difference according to the presence of LNM. Univariate and multivariate logistic regression analyses were performed to estimate the odds ratios (ORs). RESULTS: Of the 4780 UD-EGC cases, 1240 (25.9%) were identified to meet the expanded indication for ESD. Of the 1240 cases, 14 (1.1%) cases had LNM. Among the various clinical, endoscopic, and histopathological features that were evaluated, mixed histology (tumors consisting of 10%-90% of signet ring cells) had a marginally significant association (P = 0.059) with the risk of LNM. Moreover, diffuse blurring of the muscularis mucosae (MM) underneath the tumorous epithelium, a previously unrecognized histologic feature, had a significant association with the absence of LNM (P = 0.028). Multivariate logistic regression analysis showed that the blurring of MM was the only explanatory variable significantly associated with a reduced risk of LNM (OR: 0.12, 95%CI: 0.02-0.95; P = 0.045). CONCLUSION: The risk of LNM is higher than expected when using the current expanded indication for UD-EGC. Histological evaluation could provide useful clues for reducing the risk of LNM.

Long-Term Survival Outcomes of Elderly Patients Treated With S-1 or Capecitabine Plus Oxaliplatin for Stage II or III Gastric Cancer: A Multicenter Cohort Study.

Purpose: Tegafur/gimeracil/oteracil (S-1) and capecitabine plus oxaliplatin (CAPOX) are standard adjuvant chemotherapies (ACs) administered after gastrectomy to patients with stage II or III gastric cancer. However, the efficacy of AC in elderly patients remains unclear. The objective of this retrospective multicenter cohort study was to compare the efficacies of S-1 and CAPOX AC in patients aged ≥70 years. Materials and Methods: Nine hundred eighty-three patients who were treated with AC using S-1 (768 patients) or CAPOX (215 patients) were enrolled in this study. Each patient underwent AC after curative gastrectomy for stage II or III gastric cancer at one of 27 hospitals in the Republic of Korea between January 2012 and December 2013. Relapse-free survival (RFS) and overall survival (OS) were analyzed according to AC regimen and age group. Results: Of the 983 patients, 254 (25.8%) were elderly. This group had a similar RFS (P=0.099) but significantly poorer OS (p=0.003) compared with the non-elderly group. Subgroup analysis of the non-elderly group revealed no AC-associated differences in survival. Subgroup analysis of the elderly group revealed significantly better survival in the S-1 group than in the CAPOX group (RFS, P<0.001; OS, P<0.001). Multivariate analysis revealed that the CAPOX regimen was an independent poor prognostic factor for RFS (hazard ratio [HR], 1.891; 95% confidence interval [CI], 1.072-3.333; P=0.028) and OS (HR, 2.970; 95% CI, 1.550-5.692; P=0.001). Conclusions: This multicenter observational cohort study found significant differences in RFS and OS between S-1 and CAPOX AC among patients with gastric cancer aged ≥70 years.

Comparison of Standard D2 and Limited Lymph Node Dissection in Elderly Patients with Advanced Gastric Cancer.

BACKGROUND: Knowledge on the optimal extent of lymphadenectomy among elderly patients with advanced gastric cancer is limited. This study was designed to compare standard D2 and limited lymphadenectomy for evaluating the appropriate extent of lymphadenectomy. PATIENTS AND METHODS: We retrospectively reviewed patient's data based on a prospectively collected gastric cancer registry. The inclusion criteria were age above 75 years and histologically confirmed stage II or more advanced gastric cancer. In this study, 103 patients who underwent limited lymph node dissection and 134 patients who underwent standard D2 lymph node dissection were included to evaluate surgical and oncological outcomes using propensity score matching (PSM) analysis. RESULTS: The mean age after PSM was approximately 78 years in both groups. The Charlson Comorbidity Index was 5.81 ± 0.87 and 5.75 ± 0.76, respectively, and 12.5% of the patients in both groups had American Society of Anesthesiologists scores of more than 3. The limited lymphadenectomy group showed a shorter operation time and fewer retrieved lymph. However, other surgical outcomes and pathological data were not significantly different between the groups. No postoperative mortality within 30 days was observed. There were no significant differences in overall complications between the groups. The 3-year overall survival rates of the limited and standard lymphadenectomy groups were 58.3% and 73.6%, respectively. The 3-year recurrence-free survival rate of the limited lymphadenectomy group was lower than that of the standard lymphadenectomy group; however, the difference was not statistically significant. CONCLUSIONS: Standard D2 lymphadenectomy has better oncological outcomes in elderly patients with advanced gastric cancer.

Early experience of laparoscopic resection and comparison with open surgery for gastric gastrointestinal stromal tumor: a multicenter retrospective study.

The advantages of laparoscopic resection over open surgery in the treatment of gastric gastrointestinal stromal tumor (GIST) are not conclusive. This study aimed to evaluate the postoperative and oncologic outcome of laparoscopic resection for gastric GIST, compared to open surgery. We retrospectively reviewed the prospectively collected database of 1019 patients with gastric GIST after surgical resection at 13 Korean and 2 Japanese institutions. The surgical and oncologic outcomes were compared between laparoscopic and open group, through 1:1 propensity score matching (PSM). The laparoscopic group (N = 318) had a lower rate of overall complications (3.5% vs. 7.9%, P = 0.024) and wound complications (0.6% vs. 3.1%, P = 0.037), shorter hospitalization days (6.68 ± 4.99 vs. 8.79 ± 6.50, P < 0.001) than the open group (N = 318). The superiority of the laparoscopic approach was also demonstrated in patients with tumors larger than 5 cm, and at unfavorable locations. The recurrence-free survival was not different between the two groups, regardless of tumor size, locational favorableness, and risk classifications. Cox regression analysis revealed that tumor size larger than 5 cm, higher mitotic count, R1 resection, and tumor rupture during surgery were independent risk factors for recurrence. Laparoscopic surgery provides lower rates of complications and shorter hospitalizations for patients with gastric GIST than open surgery.

Prospective multicentre randomised clinical trial comparing survival rates, quality of life and nutritional status between advanced gastric cancer patients with different follow-up intensities: study protocol for the STOFOLUP trial.

INTRODUCTION: Patients who underwent curative gastrectomy for gastric cancer are regularly followed-up for the early detection of recurrence and postoperative symptom management. However, there is a lack of evidence with regard to proper surveillance intervals and diagnostic tools. This study aims to evaluate whether frequent surveillance tests have a survival benefit or improve the quality of life in patients who underwent curative resection for advanced gastric cancer. METHODS AND ANALYSIS: The STOFOLUP trial is an investigator-initiated, parallel-assigned, multicentre randomised controlled trial involving 16 hospitals in the Republic of Korea. Patients (n=886) diagnosed with pathological stage II or III gastric adenocarcinoma will be randomised to either the 3-month or the 6-month group at a 1:1 ratio, stratified by trial site and tumour stage. Patients allocated to the 3-month group will undergo an abdominal CT scan every 3 months postoperatively and those allocated to the 6-month group will undergo CT every 6 months. The primary endpoint is 3-year overall survival and the secondary endpoints are quality of life, as assessed using KOrean QUality of life in Stomach cancer patients Study group-40, the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 and the stomach cancer-specific module (STO22), and nutritional outcomes. Other survival data including data concerning 3-year disease-free survival, recurrence-free survival, gastric cancer-specific survival and postrecurrence survival will also be estimated. The first patient was enrolled on July 2021 and active patient enrolment is currently underway. ETHICS AND DISSEMINATION: This study has been approved by the Institutional Review Board of eight of the participating hospitals (NCC 2021-0085, KBSMC2021-01-059, SMC 2021-01-140, KC21OEDE0082, 4-2021-0281, AJIRB-MED-INT-20-608, 2021-0515 and H-2102-093-1198). This study will be disseminated through peer-reviewed publications, national or international conferences. TRIAL REGISTRATION NUMBER: NCT04740346.

Bariatric surgery versus medical therapy in Korean obese patients: prospective multicenter nonrandomized controlled trial (KOBESS trial).

PURPOSE: The aim of this study was to show that bariatric surgery (BS) is more effective than medical therapy (MT) in Asian obese patients. METHODS: In this prospective, multicenter, nonrandomized, controlled trial, obese patients with body mass index of ≥35 kg/m2 or 30.0-34.9 kg/m2 with obesity-related comorbidities were assigned to undergo BS, such as laparoscopic sleeve gastrectomy and Roux-en-Y gastric bypass, or MT. Patients who underwent BS were evaluated 4, 12, 24, and 48 weeks after surgery, whereas patients who received MT were monitored at a hospital every 6 weeks for 1 year. At each visit, weight, waist and hip circumference, and blood pressure were measured, and patients underwent physical examination and laboratory testing. Health-related quality of life (HQOL) was investigated using Euro QOL-5 Dimension, Impact of Weight on Quality of Life questionnaire-Lite and Obesity-related Problems scale. RESULTS: The study included 264 patients from 13 institutions; of these, 64 underwent BS and 200 received MT. Of the patients who underwent BS, 6.3% experienced early complications. Relative weight changes from baseline to 48 weeks were significantly greater in the BS than in the MT group (26.9% vs. 2.1%, P < 0.001), as were the rates of remission of diabetes (47.8% vs. 16.7%, P = 0.014), hypertension (60.0% vs. 26.1%, P < 0.001), and dyslipidemia (63.2% vs. 22.0%, P < 0.001). HQOL was better in the BS than in the MT group at 48 weeks. CONCLUSION: BS was safe and effective in Korean obese patients, with greater weight reduction, remission of comorbidities, and quality of life improvement than MT.

Short-term changes in the serum metabolome after laparoscopic sleeve gastrectomy and Roux-en-Y gastric bypass.

INTRODUCTION: Bariatric surgery is known to be the most effective treatment for weight loss in obese patients and for the rapid remission of obesity-related comorbidities. These short-term improvements result from not only limited digestion or absorption but also dynamic changes in metabolism throughout the whole body. However, short-term metabolism studies associated with bariatric surgery in Asian individuals have not been reported. OBJECTIVES: The aim of this study was to investigate the short-term metabolome changes in the serum promoted by laparoscopic sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) and to determine the underlying mechanisms that affect obesity-related comorbidities. METHODS: Serum samples were collected from Korean patients who underwent RYGB or SG before and 4 weeks after the surgery. Metabolomic and lipidomic profiling was performed using UPLC-Orbitrap-MS, and data were analyzed using statistical analysis. RESULTS: Metabolites mainly related to amino acids, lipids (fatty acids, glycerophospholipids, sphingolipids, glycerolipids) and bile acids changed after surgery, and these changes were associated with the lowering of risk factors for obesity-related diseases such as nonalcoholic fatty liver disease (NAFLD), type 2 diabetes (T2D) and atherosclerosis. Interestingly, the number of significantly altered metabolites related to the lipid metabolism were greater in SG than in RYGB. Furthermore, the metabolites related to amino acid metabolism were significantly changed only after SG, whereas bile acid changed significantly only following RYGB. CONCLUSION: These differences could result from anatomical differences between the two surgeries and could be related to the gut microbiota. This study provides crucial information to expand the knowledge of the common but different molecular mechanisms involved in obesity and obesity-related comorbidities affected by each bariatric procedure.

PRODIGY: A Phase III Study of Neoadjuvant Docetaxel, Oxaliplatin, and S-1 Plus Surgery and Adjuvant S-1 Versus Surgery and Adjuvant S-1 for Resectable Advanced Gastric Cancer.

PURPOSE: Adjuvant chemotherapy after D2 gastrectomy is standard for resectable locally advanced gastric cancer (LAGC) in Asia. Based on positive findings for perioperative chemotherapy in European phase III studies, the phase III PRODIGY study (ClinicalTrials.gov identifier: NCT01515748) investigated whether neoadjuvant docetaxel, oxaliplatin, and S-1 (DOS) followed by surgery and adjuvant S-1 could improve outcomes versus standard treatment in Korean patients with resectable LAGC. PATIENTS AND METHODS: Patients 20-75 years of age, with Eastern Cooperative Oncology Group performance status 0-1, and with histologically confirmed primary gastric or gastroesophageal junction adenocarcinoma (clinical TNM staging: T2-3N+ or T4Nany) were randomly assigned to D2 surgery followed by adjuvant S-1 (40-60 mg orally twice a day, days 1-28 every 6 weeks for eight cycles; SC group) or neoadjuvant DOS (docetaxel 50 mg/m2, oxaliplatin 100 mg/m2 intravenously day 1, S-1 40 mg/m2 orally twice a day, days 1-14 every 3 weeks for three cycles) before D2 surgery, followed by adjuvant S-1 (CSC group). The primary objective was progression-free survival (PFS) with CSC versus SC. Two sensitivity analyses were performed: intent-to-treat and landmark PFS analysis. RESULTS: Between January 18, 2012, and January 2, 2017, 266 patients were randomly assigned to CSC and 264 to SC at 18 Korean study sites; 238 and 246 patients, respectively, were treated (full analysis set). Follow-up was ongoing in 176 patients at data cutoff (January 21, 2019; median follow-up 38.6 months [interquartile range, 23.5-62.1]). CSC improved PFS versus SC (adjusted hazard ratio, 0.70; 95% CI, 0.52 to 0.95; stratified log-rank P = .023). Sensitivity analyses confirmed these findings. Treatments were well tolerated. Two grade 5 adverse events (febrile neutropenia and dyspnea) occurred during neoadjuvant treatment. CONCLUSION: PRODIGY showed that neoadjuvant DOS chemotherapy, as part of perioperative chemotherapy, is effective and tolerable in Korean patients with LAGC.