Da Vinci robot-assisted endoscopic full-thickness gastric resection with regional lymph node dissection using a 3D near-infrared video system: a single-center 5-year clinical outcome.

BACKGROUND: Endoscopic full-thickness gastric resection (EFTGR) with regional lymph node dissection (LND) has been used for early gastric cancer (EGC) exceeding the indications for endoscopic submucosal dissection (ESD). The extent of the dissected lymph nodes is crucial. A 3D near-infrared (NIR) video robot system significantly enhances visualization of the lymphatic system. However, this system has not been used in EFTGR with LND. Thus, this study assessed the benefits of the 3D NIR video robot system in a clinical setting. METHODS: Between February 2015 and September 2018, 24 patients with EGC exceeding the indications for ESD were treated with EFTGR and LND using a 3D NIR video system with the da Vinci surgical robot. Indocyanine green (ICG) was injected endoscopically around the tumor, and basin node (BN) dissection around the nodes was examined using the 3D NIR video system of the da Vinci Si surgical robot. Subsequently, robot-assisted EFTGR was performed. The primary outcome was the 5-year survival rate. RESULT: During a 5-year follow-up of all 24 patients, an 80-year-old patient with an ulcer and T2 invasion was lost to follow-up. Among the remaining 23 patients, no mortality or recurrence was observed. CONCLUSION: No metastasis or mortality occurred using the da Vinci robot-assisted EFTGR with LLND and a 3D NIR video system for patients who required radical gastrectomy for EGC in over 5 years. Hence, this may be a safe and effective method for radical gastrectomy; further studies are required confirming its effectiveness.

The Use of Histoacryl Injections to Treat Subgaleal Cerebrospinal Fluid Collection After Cranioplasty.

BACKGROUND AND OBJECTIVES: Cranioplasty is an important and basic operation in the neurosurgical field. An emergency craniectomy is performed to control malignant cerebral edema. If the patient survives, cranioplasty is performed to restore the skull defect; however, subgaleal cerebrospinal fluid collection (SCSFC) may occur. The authors aimed to identify risk factors for postoperative SCSFC and effective solutions with the subgaleal Histoacryl injection. METHODS: From January 2020 to December 2022, 154 craniectomies were performed at our hospital to relieve significant cerebral edema after traumatic brain injury; of these, 67 patients survived and underwent cranioplasty. Ten cases of postcranioplasty SCSFC were identified, among which 6 received subgaleal Histoacryl injection. RESULTS: Among the 10 SCSFC cases, 3 resolved with compression after cerebrospinal fluid aspiration, and 1 resolved after revision surgery and dural closure. Histoacryl injection was attempted for the other 6 patients. A single injection was sufficient for SCSFC resolution in 3 patients. One patient required 2 injections, and another required 3 injections. The remaining patient underwent epiduroperitoneal shunt surgery because of SCSFC persistence after 3 Histoacryl injections. Five of 6 patients (83.3%) showed an improvement of more than 80% after Histoacryl injection. CONCLUSION: Subgaleal Histoacryl injection is not considered a fundamental treatment for postoperative SCSFC but can be a successful alternative treatment.

Endoscopic Histoacryl injection for esophagojejunostomy leakage after total gastrectomy in patients with gastric cancer.

Purpose: Esophagojejunostomy leakage after total gastrectomy for gastric cancer is one of the most serious and sometimes life-threatening adverse events. The purpose of this study was to evaluate complications after total gastrectomy in patients with gastric cancer during the period when Histoacryl (B. Braun) injection was performed. Therapeutic outcome of endoscopic Histoacryl injection for esophagojejunostomy leakage was also determined. Methods: This was a single-center retrospective study. Between January 2016 and December 2021, clinicopathologic characteristics and surgical outcomes of 205 patients who underwent total gastrectomy were investigated. Baseline characteristics and clinical outcomes of 10 patients with esophagojejunostomy leakage were also investigated. Results: Postoperative complication and mortality rates of total gastrectomy in 205 patients were 25.4% and 0.9%, respectively. Serious complications more than Clavien-Dindo IIIb accounted for 6.3%. Ten (4.9%) esophagojejunostomy leakages occurred in 205 patients. Among 10 esophagojejunostomy leakage patients, endoscopic Histoacryl injection was performed on eight patients and leakage was successfully managed with endoscopic Histoacryl injection in seven patients (87.5%). Mean postinjection hospital stay of seven successfully managed patients was 13.8 days. They were able to drink water at 1-6 days after injection. Among eight patients with endoscopic Histoacryl injection, six patients were injected once and two patients were injected three times. Conclusion: Endoscopic Histoacryl injection for esophagojejunostomy leakage after total gastrectomy can be considered as a useful treatment for some selected cases.

Semi-Permanent Use of Indocyanine Green Latex Phantom for Fluorescence Emission.

INTRODUCTION: Testing the fluorescence emission of the vascular circulation status of the indocyanine green (ICG) fluorescence contrast agent to validate the system performance is crucial. Hence, the development of an ICG phantom is imperative, and this study proposes a method for manufacturing an ICG phantom. METHOD: The ICG with an initial concentration was subjected to 0.2 cc sampling through syringe(x), and an ICG (0.2 cc) is diluted with silicon (Si) latex lubber (10 mL) during the manufactured the phantom. The brightest fluorescence expression state is 30 µM, and if it exceeded 50 µM, fluorescence fading occurred and changed to a dark color. RESULTS: The liquid (ICG) of the concentration range is 0.003 mM to 0.24 mM, and the maximum fluorescence expression range is 0.005 to 0.006 mM when the phantom is irradiated using a 780-nm (800 mW) LED. In addition, the fluorescence emission is reduced to 0.24 mM, and the fluorescence expression concentration is 10 µM, 30 µM, and 50 µM, respectively. The decreasing of the fluorescence emission is beginning to 50 µM. CONCLUSIONS: In this study, the proposed phantom with ICG fluorescence emission using latex lubber is proposed. In this works, the proposed phantom is improved the performance for ICG fluorescence emission. In the manufactured phantom, the phantom is used for gelatin, and the advance of phantom has easy manufacturing and long-life fluorescence emission (semipermanent) due to incorrodible material (latex lubber). To experimental results of a phantom, the ICG fluorescent contrast medium (0.055 mM) is same to 30 µM. Then, the 0.055 mM and 30 µM have high resolution and fluorescence emission status. Thus, the results are in good agreement.

Predictive Value of KLASS-02-QC Assessment Score on KLASS-02 Surgical Outcomes: Validation of Surgeon Quality Control and Standardization for D2 Lymphadenectomy.

OBJECTIVE: The aim of this study was to audit the 22 items and assessed each item's predictive value on surgical outcomes. BACKGROUND: The KLASS-02 trial revealed that the oncologic outcomes of laparoscopic distal gastrectomy are not inferior to open distal gastrectomy in patients with advanced gastric cancer. The surgeons participating in this trial were chosen based on the assessment scores from the KLASS-02-QC trial, which used 22 items for standardization of D2 lymphadenectomy and quality control. METHODS: We reviewed proficiency scores (PSs) for 22 items for 20 surgeons who participated in KLASS-02. The surgeons were divided into 2 groups according to PS, and the perioperative outcomes of 924 patients enrolled in KLASS-02 were compared between groups. Each item's predictive value for perioperative outcome was then assessed using multivariable regression models. RESULTS: Of the total 924 patients, 529 were operated on by high-score surgeons (high PS) and 395 were operated on by low-score surgeons (low-PS). High-PS group had less intraoperative blood loss, longer operation times, and fewer complications, major complications, reoperations, and shorter first flatus and hospital stay than low-PS group ( P =0.006, P <0.001, P <0.001, P <0.001, P =0.042, P =0.013, and P <0.001, respectively). Some items used in KLASS-02-QC predicted perioperative outcomes, such as intraoperative blood loss, major complications, reoperation, and hospital stay. CONCLUSIONS: Although this study only analyzed data associated with qualified surgeons, the 22 items effectively assessed the surgeons based on PS. A high score was associated with longer operation times, but better perioperative outcomes.

Standard follow-up after curative surgery for advanced gastric cancer: secondary analysis of a multicentre randomized clinical trial (KLASS-02).

BACKGROUND: The benefit of regular follow-up after curative resection for gastric cancer is controversial as there is no evidence that it will improve survival. This study assessed whether regular follow-up leads to improved survival in patients after surgery for gastric cancer. METHODS: A secondary analysis was undertaken of patients who participated in an RCT of laparoscopic versus open distal gastrectomy for advanced gastric cancer between November 2011 and April 2015. Depending on whether patients were compliant with the initial trial follow-up protocol or not, they were analysed as having had either regular or irregular follow-up. Clinicopathological characteristics, recurrence patterns, detection, treatments, and survival were compared between the groups. RESULTS: The regular and irregular follow-up groups comprised 712 and 263 patients respectively. Disease recurrence within 36 months was more common in the regular group than in the irregular group (17.0 versus 11.4 per cent; P = 0.041). Recurrence patterns did not differ between the groups. The 3-year recurrence-free survival rate was worse in the regular than in the irregular group (81.2 versus 86.5 per cent; P = 0.031). However, the 5-year overall survival rate was comparable (84.5 versus 87.5 per cent respectively; P = 0.160). Multivariable analysis revealed that type of follow-up was not an independent factor affecting 5-year overall survival. CONCLUSION: Regular follow-up after radical gastrectomy was not associated with improved overall survival.

Accuracy of preoperative clinical staging for locally advanced gastric cancer in KLASS-02 randomized clinical trial.

Purpose: The discrepancy between preoperative and final pathological staging has been a long-standing challenge for the application of clinical trials or appropriate treatment options. This study aimed to demonstrate the accuracy of preoperative staging of locally advanced gastric cancer using data from a large-scale randomized clinical trial. Materials and methods: Of the 1050 patients enrolled in the clinical trial, 26 were excluded due to withdrawal of consent (n = 20) or non-surgery (n = 6). The clinical and pathological staging was compared. Risk factor analysis for underestimation was performed using univariate and multivariate analyses. Results: Regarding T staging by computed tomography, accuracy rates were 74.48, 61.62, 58.56, and 85.16% for T1, T2, T3 and T4a, respectively. Multivariate analysis for underestimation of T staging revealed that younger age, ulcerative gross type, circular location, larger tumor size, and undifferentiated histology were independent risk factors. Regarding nodal status estimation, 54.9% of patients with clinical N0 disease were pathologic N0, and 36.4% of patients were revealed to have pathologic N0 among clinical node-positive patients. The percentage of metastasis involvement at the D1, D1+, and D2 lymph node stations significantly increased with the advanced clinical N stage. Among all patients, 29 (2.8%), including 26 with peritoneal seeding, exhibited distant metastases. Conclusions: Estimating the exact pathologic staging remains challenging. A thorough evaluation is mandatory before treatment selection or trial enrollment. Moreover, we need to set a sufficient case number when we design the clinical trial considering the stage migration.

Laparoscopic vs Open Distal Gastrectomy for Locally Advanced Gastric Cancer: 5-Year Outcomes of the KLASS-02 Randomized Clinical Trial.

Importance: The long-term safety of laparoscopic distal gastrectomy for locally advanced gastric cancer (AGC) remains uncertain given the lack of 5-year follow-up results. Objective: To compare the 5-year follow-up results in patients with clinically AGC enrolled in the Korean Laparoendoscopic Gastrointestinal Surgery Study (KLASS)-02 randomized clinical trial who underwent laparoscopic or open distal gastrectomy. Design, Setting, and Participants: The KLASS-02, a multicenter randomized clinical trial, showed that laparoscopic surgery was noninferior to open surgery for patients with locally AGC. The present study assessed the 5-year follow-up results, including 5-year overall survival (OS) and relapse-free survival (RFS) rates and long-term complications, in patients enrolled in KLASS-02. From November 21, 2011, to April 29, 2015, patients aged 20 to 80 years diagnosed preoperatively with locally AGC were enrolled. Final follow-up was on June 15, 2021. Data were analyzed June 24 to September 9, 2021. Interventions: Patients were treated with R0 resection either by laparoscopic gastrectomy or open gastrectomy as the full analysis set of the KLASS-02 trial. Main Outcomes and Measures: Five-year OS and RFS rates, recurrence patterns, and long-term surgical complications were evaluated. Results: This study enrolled a total of 1050 patients. A total of 974 patients were treated with R0 resection; 492 (50.5%) in the laparoscopic gastrectomy group (mean [SD] age, 59.8 [11.0] years; 351 men [71.3%]) and 482 (49.5%) in the open gastrectomy group (mean [SD] age, 59.4 [11.5] years; 335 men [69.5%]). In patients who underwent laparoscopic and open distal gastrectomy, the 5-year OS (88.9% vs 88.7%) and RFS (79.5% vs 81.1%) rates did not differ significantly. The most common types of recurrence were peritoneal carcinomatosis (73 of 173 [42.1%]), hematogenous metastases (36 of 173 [20.8%]), and locoregional recurrence (23 of 173 [13.2%]), with no between-group differences in types of recurrence at each cancer stage. The correlation between 3-year RFS and 5-year OS at the individual level was highest in patients with stage III gastric cancer (ρ = 0.720). The late complication rate was significantly lower in the laparoscopic than in the open surgery group (32 of 492 [6.5%] vs 53 of 482 [11.0%]). The most common type of complication in both groups was intestinal obstruction (13 of 492 [2.6%] vs 24 of 482 [5.0%]). Conclusions and Relevance: The 5-year outcomes of the KLASS-02 trial support the 3-year results, which is the noninferiority of laparoscopic surgery compared with open gastrectomy for locally AGC. The laparoscopic approach can be recommended in patients with locally AGC to achieve the benefit of low incidence of late complications. Trial Registration: ClinicalTrials.gov Identifier: NCT01456598.

Difference in the prevalence of advanced colon adenoma between patients with gastric neoplasm and healthy people: A STROBE-compliant study.

ABSTRACT: We compared the prevalence of adenoma and cancerous colon polyps in patients undergoing endoscopic removal or gastric surgery for gastric adenoma or gastric cancer and in healthy individuals.The medical records of 707 patients with gastric neoplasm and 798 age- and sex-matched healthy subjects were retrospectively analyzed between January 2010 and July 2018. The clinicopathological characteristics, prevalence of colorectal neoplasm diagnosed by colonoscopy, and risk factors for colorectal polyps were also investigated.When comparing the two groups, the prevalence of overall colorectal polyps and its distribution was not different between the two groups (54.0% vs.49.5%, P = .079), whereas, the number of colon polyps (1.20 ±â€Š1.71 vs 0.99 ±â€Š1.54, P = .015) and the maximal size (3.53 ±â€Š6.14 vs 2.08 ±â€Š2.88, P < .001) were significantly larger in the gastric neoplasm group. The prevalence of advanced colon adenoma was significantly higher in the gastric neoplasm group (10.7% vs 3.8%, P < .001). Risk factors such as elevated glucose levels and the presence of gastric neoplasm were related to the prevalence of all colon polyps. The presence of gastric neoplasm is an important risk factor for advanced colon polyps.Patients with gastric neoplasms had a significantly higher prevalence of advanced colon adenoma. Advanced colon adenoma is associated with the chain from benign adenomas through malignant altered adenomas to advanced colon cancer. Thus, patients with gastric neoplasm are regarded as a high-risk group for colorectal cancer and are recommended for screening colonoscopy at the time of diagnosis.

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.

Local complications are related to poor long-term outcome in patients undergoing curative gastrectomy for advanced gastric cancer.

Purpose: The present study was performed to investigate the effects of local complications (LC) on long-term survival and cancer recurrence in patients undergoing curative gastrectomy for gastric cancer. Methods: We analyzed 2,627 patients after curative gastrectomy for gastric cancer between January 2001 and December 2006. Patients were classified into groups no complications (NC), LC, or systemic complications (SC). Results: Among the 2,627 patients, 475 patients developed complications (LC group [n=374, 14.2%] and SC group [n=101, 3.9%]). The 5-year cancer-specific survival rate was significantly poorer in the LC group compared to the NC and SC groups (LC, 78.0%; NC, 85.4%; SC, 80.2%; P=0.007). The occurrence of LC was identified as a significant independent prognostic factor for overall and cancer-specific survival (hazard ratio [HR], 2.08; 95% confidence interval [CI], 1.46-2.97; P=0.001 and HR, 1.77; 95% CI, 1.12-2.81; P=0.015). The tumor recurrence rates were higher in the LC group than the in other two groups (LC, 23.5%; NC, 15.4%; SC, 15.8%; P<0.001). The occurrence of LC was an independent predictor of tumor recurrence in patients undergoing curative gastrectomy for gastric cancer (HR, 1.55; 95% CI, 1.11-2.17; P=0.011). Conclusion: LC are associated with adverse long-term outcomes in patients after curative gastrectomy for advanced gastric cancer.

Rare minisatellite alleles of MUC2-MS8 influence susceptibility to rectal carcinoma.

BACKGROUND: Previously, we identified eight novel minisatellites in the MUC2, of which allelic variants in MUC2-MS6 were examined to influence susceptibility to gastric cancer. However, studies on the susceptibility to gastrointestinal cancer of other minisatellites in the MUC2 region still remain unprogressive. OBJECTIVE: In this study, we investigated whether polymorphic variations in the MUC2-MS8 region are related to susceptibility to gastrointestinal cancer. METHODS: We assessed the association between MUC2-MS8 and gastrointestinal cancers by a case-control study with 1229 controls, 486 gastric cancer cases, 220 colon cancer cases and 278 rectal cancer cases. To investigate whether intronic minisatellites affect gene expression, various minisatellites were inserted into the luciferase-reporter vector and their expression levels were examined. We also examined the length of MUC2-MS8 alleles in blood and cancer tissue matching samples of 107 gastric cancer patients, 125 colon cancer patients, and 85 rectal cancer patients, and investigated whether the repeat sequence affects genome instability. RESULTS: A statistically significant association was identified between rare MUC2-MS8 alleles and the occurrence of rectal cancer: odds ratio (OR), 6.66; 95% confidence interval (CI), 1.11-39.96; and P = 0.0165. In the younger group (age, < 55), rare alleles were significant associated with an increased risk of rectal cancer (odds ratio, 24.93 and P = 0.0001). Suppression of expression was found in the reporter vector inserted with minisatellites, and loss of heterozygosity (LOH) of the MUC2-MS8 region was confirmed in cancer tissues of gastrointestinal cancer patients (0.8-5.9%). CONCLUSION: Our results suggest that the rare alleles of MUC2-MS8 could be used to identify the risk of rectal cancer and that this repeat region is related to genomic instability.

Surgeon Quality Control and Standardization of D2 Lymphadenectomy for Gastric Cancer: A Prospective Multicenter Observational Study (KLASS-02-QC).

OBJECTIVE: To qualify surgeons to participate in a randomized trial comparing laparoscopic and open distal D2 gastrectomy for advanced gastric cancer. SUMMARY OF BACKGROUND DATA: No studies have sought to qualify surgeons for a randomized trial comparing laparoscopic and open D2 gastrectomy for advanced gastric cancer. METHODS: We conducted a multicenter prospective observational study evaluating unedited videos of laparoscopic and open D2 gastrectomy performed by 27 surgeons. Surgeons performed 3 of each laparoscopic and open distal gastrectomies with D2 lymphadenectomy for gastric cancer. Five peers reviewed each unedited video using a video assessment form. Based on experts' review of videos, a separate review committee decided surgeons as "Qualified" or "Not-qualified." RESULTS: Twelve surgeons (44.4%) were qualified on initial evaluation whereas the other 15 surgeons were not. Another 9 surgeons were finally qualified after re-evaluation. The median score for Qualified was significantly higher than Not-qualified (P < 0.001).Significant differences between Qualified and Not-qualified were noted both in operation type and in all evaluation area of surgical skill, perigastric, and extra-perigastric lymphadenectomy, although the inter-rater variability of the assessment score was low (kappa = 0.285). However, Not-qualified surgeons' scores improved upon re-evaluation of resubmitted videos.When compared laparoscopy with open surgery, median scores were similar between the 2 groups (P = 0.680). However, open gastrectomy scores for surgical skills were significantly higher than for laparoscopic surgery (P = 0.016). CONCLUSIONS: Our surgeon quality control study for gastrectomy represents a milestone in surgical standardization for surgical clinical trials. Our methods could also serve as a system for educating surgeons and assessing surgical proficiency.

Comparison of surgical outcomes among different methods of esophagojejunostomy in laparoscopic total gastrectomy for clinical stage I proximal gastric cancer: results of a single-arm multicenter phase II clinical trial in Korea, KLASS 03.

BACKGROUND: Laparoscopic distal gastrectomy for early gastric cancer has been widely accepted, but laparoscopic total gastrectomy has still not gained popularity because of technical difficulty and unsolved safety issue. We conducted a single-arm multicenter phase II clinical trial to evaluate the safety and the feasibility of laparoscopic total gastrectomy for clinical stage I proximal gastric cancer in terms of postoperative morbidity and mortality in Korea. The secondary endpoint of this trial was comparison of surgical outcomes among the groups that received different methods of esophagojejunostomy (EJ). METHODS: The 160 patients of the full analysis set group were divided into three groups according to the method of EJ, the extracorporeal circular stapling group (EC; n = 45), the intracorporeal circular stapling group (IC; n = 64), and the intracorporeal linear stapling group (IL; n = 51). The clinicopathologic characteristics and the surgical outcomes were compared among these three groups. RESULTS: There were no significant differences in the early complication rates among the three groups (26.7% vs. 18.8% vs. 17.6%, EC vs. IC vs. IL; p = 0.516). The length of mini-laparotomy incision was significantly longer in the EC group than in the IC or IL group. The anastomosis time was significantly shorter in the EC group than in the IL group. The time to first flatus was significantly shorter in the IL group than in the EC group. The long-term complication rate was not significantly different among the three groups (4.4% vs. 12.7% vs. 7.8%; EC vs. IC vs. IL; p = 0.359), however, the long-term incidence of EJ stenosis in IC group (10.9%) was significantly higher than in EC (0%) and IL (2.0%) groups (p = 0.020). CONCLUSIONS: The extracorporeal circular stapling and the intracorporeal linear stapling were safe and feasible in laparoscopic total gastrectomy, however, intracorporeal circular stapling increased EJ stenosis.

Extradural Spinal Arachnoid Cyst as a Cause of Cauda Equina Syndrome in a Child.

Although spinal arachnoid cysts are relatively common findings observed incidentally in adults, they are much rarely reported in children. They are usually asymptomatic and are mainly located in the middle and lower thoracic regions. However, in rare circumstances, these cysts can cause mass effects that lead to neurologic symptoms. We report the rare case of a spinal extradural arachnoid cyst in a 12-year-old boy who showed signs and symptoms of cauda equina syndrome. Magnetic resonance imaging of the lumbar spine revealed a huge extradural arachnoid cyst extending from L2 to L5. Emergent laminectomy and repair of dural defect was performed after total resection of the extradural arachnoid cyst. There were no postoperative complications. Total recovery was achieved 6 months after surgery. Here, we report this rare case with a review of the literature.

The pattern of postoperative quality of life following minimally invasive gastrectomy for gastric cancer: a prospective cohort from Korean multicenter robotic gastrectomy trial.

PURPOSE: Quality of life (QOL) has become important in the trend of emphasizing patient satisfaction. This study aimed to evaluate the QOL in patients who underwent laparoscopic or robotic gastrectomy for gastric cancer. METHODS: A prospective trial was performed involving patients who underwent laparoscopic or robotic gastrectomy for primary gastric cancer at 11 hospitals in Korea. Within this comparative trial, QOL, postoperative pain, and long-term complications were exanimated. The quality-of-life questionnaire (QLQ)-C30 and QLQ-STO22 developed by the European Organization for Research and Treatment of Cancer were used for the QOL survey. We compared the data after dividing it into several types of characteristics as follows; device (robotic or laparoscopic), operation type, pathological stage, and sex. Biased components were extracted by logistic regression analysis. Propensity score matching was applied to the data set with the biased components. RESULTS: In total, 434 patients (211 for laparoscopic surgery and 223 for robotic surgery) were enrolled, out of which 321 patients who responded to both preoperative and postoperative surveys were selected for analysis. Robotic gastrectomy was not different from laparoscopic gastrectomy with respect to postoperative QOL. Distal gastrectomy showed better scores than total gastrectomy in terms of role functioning, social functioning, fatigue, nausea/vomiting, pain, dyspnea, constipation, financial difficulties, dysphagia, eating restrictions, anxiety, taste, and body image. Male patients showed better scores on the 19 scales compared to female patients. CONCLUSION: Robotic and laparoscopic approaches for gastric cancer surgery did not differ from each other with respect to QOL. Distal gastrectomy resulted in better QOL than total gastrectomy.

Long-Term Outcomes of Laparoscopic Distal Gastrectomy for Locally Advanced Gastric Cancer: The KLASS-02-RCT Randomized Clinical Trial.

PURPOSE: It is unclear whether laparoscopic distal gastrectomy for locally advanced gastric cancer is oncologically equivalent to open distal gastrectomy. The noninferiority of laparoscopic subtotal gastrectomy with D2 lymphadenectomy for locally advanced gastric cancer compared with open surgery in terms of 3-year relapse-free survival rate was evaluated. PATIENTS AND METHODS: A phase III, open-label, randomized controlled trial was conducted for patients with histologically proven locally advanced gastric adenocarcinoma suitable for distal subtotal gastrectomy. The primary end point was the 3-year relapse-free survival rate; the upper limit of the hazard ratio (HR) for noninferiority was 1.43 between the laparoscopic and open distal gastrectomy groups. RESULTS: From November 2011 to April 2015, 1,050 patients were randomly assigned to laparoscopy (n = 524) or open surgery (n = 526). After exclusions, 492 patients underwent laparoscopic surgery and 482 underwent open surgery and were included in the analysis. The laparoscopy group, compared with the open surgery group, suffered fewer early complications (15.7% v 23.4%, respectively; P = .0027) and late complications (4.7% v 9.5%, respectively; P = .0038), particularly intestinal obstruction (2.0% v 4.4%, respectively; P = .0447). The 3-year relapse-free survival rate was 80.3% (95% CI, 76.0% to 85.0%) for the laparoscopy group and 81.3% (95% CI, 77.0% to 85.0%; log-rank P = .726) for the open group. Cox regression analysis after stratification by the surgeon revealed an HR of 1.035 (95% CI, 0.762 to 1.406; log-rank P = .827; P for noninferiority = .039). When stratified by pathologic stage, the HR was 1.020 (95% CI, 0.751 to 1.385; log-rank P = .900; P for noninferiority = .030). CONCLUSION: Laparoscopic distal gastrectomy with D2 lymphadenectomy was comparable to open surgery in terms of relapse-free survival for patients with locally advanced gastric cancer. Laparoscopic distal gastrectomy with D2 lymphadenectomy could be a potential standard treatment option for locally advanced gastric cancer.

Short-term Outcomes of a Multicenter Randomized Controlled Trial Comparing Laparoscopic Distal Gastrectomy With D2 Lymphadenectomy to Open Distal Gastrectomy for Locally Advanced Gastric Cancer (KLASS-02-RCT).

OBJECTIVE: The aim of the study was to evaluate the short-term outcomes of KLASS-02-RCT, a multicenter randomized controlled trial comparing laparoscopic distal gastrectomy (LDG) with D2 lymphadenectomy with open distal gastrectomy (ODG). SUMMARY BACKGROUND DATA: Although several benefits of laparoscopic gastric cancer surgery have been reported, strong evidence is still limited, especially in locally advanced gastric cancer which requires extensive lymph node dissection. METHODS: Enrollment criteria included histologically confirmed cT2-4a and N0-1 gastric adenocarcinoma. Thirty-day morbidity, 90-day mortality, postoperative pain, and recovery were compared between LDG and ODG groups. RESULTS: A total of 1050 patients were randomly assigned to LDG (n = 526) or ODG group (n = 524) between November 2011 and April 2015. After excluding patients who received bypass or no surgery, 1011 patients were analyzed as actual treatment group. Mean number of totally retrieved lymph nodes was similar in both groups (LDG = 46.6 vs ODG = 47.4, P = 0.451). Early morbidity rate was significantly lower after LDG (16.6%) than after ODG (24.1%; P = 0.003). Postoperative analgesics use and patients' reported pain score were significantly lower after LDG. First day of flatus was earlier after LDG (3.5 vs 3.7 d, P = 0.025) and postoperative hospital stay was shorter in LDG group (8.1 vs 9.3 d, P = 0.005). Ninety days' mortality rate was similar in both groups (LDG = 0.4% vs ODG = 0.6%, P = 0.682). CONCLUSIONS: Laparoscopic distal gastrectomy with D2 lymphadenectomy for locally advanced gastric cancer shows benefits in terms of lower complication rate, faster recovery, and less pain compared with open surgery.

Operation time as a simple indicator to predict the overcoming of the learning curve in gastric cancer surgery: a multicenter cohort study.

BACKGROUND: The aim of this study is to identify an indicator to predict the overcoming of the learning curve of distal gastrectomy in gastric cancer surgery. METHOD: A retrospective multicenter cohort study was conducted in 2100 patients who underwent radical distal gastrectomy performed by nine surgeons in eight hospitals between 2001 and 2006. For each surgeon, an individual CUSUM chart was formulated in terms of operation time or clinical outcomes, including severe complications, number of retrieved lymph nodes, positive resection margin, and hospital stay. The actual changing points (CPs) of the CUSUM charts were analyzed. Based on the CP, patients were divided into pre-CP and post-CP groups, and the clinicopathologic outcomes and survival data were compared between the groups. RESULTS: CP determined by operation time was more reliable than CP determined by a combination of clinical outcomes, as the former was correlated not only with short-term outcomes but also with survival. The outcomes were superior in the post-CP group in terms of numbers of harvested lymph nodes, sufficient lymph node harvesting (> 15), and negative proximal margins. In a survival analysis, the post-CP group showed better survival than the pre-CP group in stage II (76% vs 86.1% p = 0.010) and stage III (51.5% vs 60.6% p = 0.042). CONCLUSION: Overcoming the learning curve of distal gastrectomy for gastric cancer can be better predicted by operation time rather than by a combination of postoperative clinical parameters. It is recommended that surgeons initially operate on early stage cancer patients before overcoming the learning curve.

Effect of Laparoscopic Distal Gastrectomy vs Open Distal Gastrectomy on Long-term Survival Among Patients With Stage I Gastric Cancer: The KLASS-01 Randomized Clinical Trial.

IMPORTANCE: Laparoscopic distal gastrectomy is gaining popularity over open distal gastrectomy for gastric cancer because of better early postoperative outcomes. However, to our knowledge, no studies have proved whether laparoscopic distal gastrectomy is oncologically equivalent to open distal gastrectomy. OBJECTIVE: To examine whether the long-term survival among patients with stage I gastric cancer undergoing laparoscopic distal gastrectomy is noninferior to that among patients undergoing open distal gastrectomy. DESIGN: The Korean Laparoendoscopic Gastrointestinal Surgery Study (KLASS) group, which includes 15 surgeons from 13 institutes, conducted a phase 3, multicenter, open-label, noninferiority, prospective randomized clinical trial (KLASS-01) of patients with histologically proven, preoperative clinical stage I gastric adenocarcinoma from January 5, 2006, to August 23, 2010. Survival and recurrence status of the patients was determined in December 2016. INTERVENTIONS: Patients were randomly assigned (1:1) to laparoscopic distal gastrectomy (n = 705) or open distal gastrectomy (n = 711). Of these patients, 85 received a surgical approach opposite the one to which they were randomized (63 randomized to the open surgery group and 22 to the laparoscopic group). MAIN OUTCOMES AND MEASURES: Difference in 5-year overall survival between the laparoscopic and open distal gastrectomy groups. The noninferiority margin was prespecified as -5% (corresponding hazard ratio of 1.54), with an assumed survival of 90% after 5 years in the open surgery group. RESULTS: Among the 1416 patients (mean [SD] age, 57.3 [11.1] years; 940 [66.4%] male) included in the study, the 5-year overall survival rates were 94.2% in the laparoscopic group and 93.3% in the open surgery group (log-rank P = .64). Intention-to-treat analysis confirmed the noninferiority of the laparoscopic approach compared with the open approach (difference, 0.9 percentage points; 1-sided 97.5% CI, -1.6 to infinity). The 5-year cancer-specific survival rates were similar between the 2 groups (97.1% in the laparoscopic group and 97.2% in the open surgery group, log-rank P = .91; difference, -0.03 percentage points; 1-sided 97.5% CI, -1.8 to infinity). Per-protocol analysis results were consistent with the intention-to-treat results for overall and cancer-specific survival rates. CONCLUSIONS AND RELEVANCE: The KLASS-01 trial revealed similar overall and cancer-specific survival rates between patients receiving laparoscopic and open distal gastrectomy. Laparoscopic distal gastrectomy is an oncologically safe alternative to open surgery for stage I gastric cancer. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT00452751.