Clinical Efficacy of Laparoscopic Sentinel Node Navigation Surgery for Stomach Preservation in Patients With Early Gastric Cancer: 5-year Results of the SENORITA Trial.

OBJECTIVE: This study aimed to compare laparoscopic standard gastrectomy (LSG) and laparoscopic sentinel node navigation surgery (LSNNS) for EGC in terms of 5-year long-term oncologic outcomes. SUMMARY BACKGROUND DATA: The oncological safety of LSNNS for early gastric cancer (EGC) has not been confirmed. Three-year disease-free survival (DFS), which is the primary endpoint of the phase III multicenter randomized controlled clinical trial (SEntinel Node ORIented Tailored Approach [SENORITA] trial), did not show the non-inferiority of LSNNS relative to LSG. METHODS: The SENORITA trial, a multicenter randomized clinical trial, was designed to show that LSNNS is non-inferior to LSG in terms of 3-year DFS. In the present study, we collected 5-year follow-up data from 527 patients recruited in the SENORITA trial as the full analysis set (FAS). Disease-free survival (DFS), overall survival (OS), disease-specific survival (DSS), and recurrence patterns were evaluated using the FAS of both LSG (n=269) and LSNNS (n=258). RESULTS: The 5-year DFS was not significantly different between the LSG and LSNNS groups (P=0.0561). During the 5-year follow-up, gastric cancer-related events, such as metachronous cancer, were more frequent in the LSNNS group than in the LSG group. However, ten recurrent cancers in the remnant stomach of both groups were curatively resected by additional gastrectomy and one by additional endoscopic resection. Two of the 198 patients who underwent local resection for stomach preservation based on the LSNNS results developed distant metastasis. However, there was no statistically significant difference in the 5-year OS and DSS (P=0.7403 and P=0.9586, respectively) between the two groups. CONCLUSION: The 5-year DFS, DSS and OS did not differ significantly between the two groups. Considering the benefits of LSNNS on postoperative quality of life, LSNNS could be recommended as an alternative treatment option for EGC.

Laparoscopic Pylorus Preserving Gastrectomy vs Distal Gastrectomy for Early Gastric Cancer; A Multicenter Randomized Controlled Trial (KLASS-04).

OBJECTIVE: To evaluate the long-term outcomes of laparoscopic pylorus preserving gastrectomy (LPPG) with laparoscopic distal gastrectomy (LDG) for early gastric cancer (EGC). SUMMARY BACKGROUND DATA: PPG is considered as a function preserving surgery for EGC. However, there has been no multicenter randomized controlled trial comparing PPG with DG until now. METHODS: A multicenter randomized controlled trial (KLASS-04) with 256 patients with cT1N0M0 gastric cancer located in the mid portion of the stomach was conducted. The primary endpoint was the incidence of dumping syndrome at postoperative 1 year. Secondary endpoints included survival and recurrence, gallstone formation, nutritional parameters, gastroscopic findings, and quality of life (QOL) for 3 years. RESULTS: In the intention-to-treat analyses, there was no difference in the incidence of dumping syndrome at one year postoperatively (13.2% in LPPG vs. 15.8% in LDG, P=0.622). Gallstone formation after surgery was significantly lower in LPPG than in LDG (2.33% vs. 8.66%, P=0.026). Hemoglobin (+0.01 vs. -0.76 gm/dL, P<0.001) and serum protein (-0.15 vs. -0.35 gm/dL, P=0.002) were significantly preserved after LPPG. However, reflux esophagitis (17.8% vs. 6.3%, P=0.005) and grade IV delayed gastric emptying (16.3% vs. 3.9%, P=0.001) were more common in LPPG. Changes in body weight and postoperative QOL were not significantly different between groups. Three-year overall survival and disease-free survival were not different (1 case of recurrence of in each group, P=0.98). CONCLUSIONS: LPPG can be used as an alternative surgical option for cT1N0M0 gastric cancer in the mid portion of the stomach.

Feasibility of Regional Lymphadenectomy for Stomach-Preserving Surgery in Early Gastric Cancer Omitting Sentinel Node Navigation: A Post Hoc Analysis of the SENORITA Trial.

BACKGROUND: Sentinel node navigation (SNN) has been known as the effective treatment for stomach-preserving surgery in early gastric cancer; however, SNN presents several technical difficulties in real practice. OBJECTIVE: This study aimed to evaluate the feasibility of regional lymphadenectomy omitting SNN, using the post hoc analysis of a randomized controlled trial. METHODS: Using data from the SENORITA trial that compared laparoscopic standard gastrectomy with lymphadenectomy and laparoscopic SNN, 237 patients who underwent SNN were included in this study. Tumor location was divided into longitudinal and circumferential directions. According to the location of the tumor, the presence or absence of lymph node (LN) metastases between sentinel and non-sentinel basins were analyzed. Proposed regional LN stations were defined as the closest area to the primary tumor. Sensitivities, specificities, positive predictive values, and negative predictive values (NPV) of SNN and regional lymphadenectomy were compared. RESULTS: Metastasis to non-sentinel basins with tumor-free in sentinel basins was observed in one patient (0.4%). The rate of LN metastasis to non-regional LN stations without regional LN metastasis was 2.5% (6/237). The sensitivity and NPV of SNN were found to be significantly higher than those of regional lymphadenectomy (96.8% vs. 80.6% [p = 0.016] and 99.5% vs. 97.2% [p = 0.021], respectively). CONCLUSIONS: This study showed that regional lymphadenectomy for stomach-preserving surgery, omitting SNN, was insufficient; therefore, SNN is required in stomach-preserving surgery.

Feasibility of intraoperative pathologic examination for sentinel lymph nodes during sentinel node navigation surgery in early gastric cancer: results of pathologic protocol for SENORITA trial.

BACKGROUND: During sentinel node navigation surgery in patients with gastric cancer, intraoperative pathologic examination of sentinel nodes is crucial in determining the extent of surgery. In this study, we evaluated the feasibility and accuracy of intraoperative pathologic protocols using data from a prospective, multicenter, randomized trial. METHODS: A retrospective analysis was conducted using data from the SEntinel Node ORIented Tailored Approach trials from 2013 to 2016. All sentinel lymph nodes were evaluated during surgery with hematoxylin-eosin (HE) staining using a representative section at the largest plane for lymph nodes. For permanent histologic evaluation, sentinel basin nodes were stained with HE and cytokeratin immunohistochemistry in formalin-fixed, paraffin-embedded (FFPE) sections and examined with HE for three deeper-step sections at 200-µm intervals. The failure rate of identification by frozen section and the metastasis rate in non-sentinel basins were investigated. RESULTS: Of the 237 patients who underwent sentinel node basin dissection, 30 had lymph node metastases on permanent pathology. Thirteen patients had macrometastasis confirmed in frozen sections as well as FFPE sections (failure rate: 0%). Patients with negative sentinel nodes in frozen sections but micrometastasis in FFPE sections had no lymph node recurrence during the follow-up period (0%, 0/6). However, in cases with tumor-positive nodes in frozen sections, metastases in non-sentinel basins were detected in the paraffin blocks (8.3%, 2/24). CONCLUSIONS: The single-section HE staining method is sufficient for detecting macrometastasis via intraoperative pathological examination. If a negative frozen-section result is confirmed, sentinel basin dissection can be performed safely. Otherwise, standard surgery is required.

A pilot clinical study to evaluate feasibility of using single patient classifier as a prognostic test in stage II-III gastric cancer patients.

Objective: Precision medicine approaches emphasize the importance of reliable prognostic tools for guiding individualized therapy decisions. In this study, we evaluated the clinical feasibility of the single patient classifier (SPC) test, a new clinical-grade prognostic assay, in stage II-III gastric cancer patients. Methods: A prospective multicenter study was conducted, involving 237 patients who underwent gastrectomy between September 2019 and August 2020 across nine hospitals. The SPC test was employed to stratify patients into risk groups, and its feasibility and performance were evaluated. The primary endpoint was the proportion of the cases in which the test results were timely delivered before selecting postoperative treatment. Furthermore, 3-year disease-free survivals of risk groups were analyzed. Results: The SPC test met the primary endpoint criteria. The 99.5% of SPC tests were timely delivered to hospitals before the postoperative treatment started. In a clinical setting, the median time from the specimen transfer to laboratory to the result delivery to hospital was 4 d. Furthermore, 3-year disease-free survivals were significantly different between risk groups classified with SPC tests. Conclusions: This study highlights the SPC test's feasibility in offering crucial information timely delivered for making informed decisions regarding postoperative treatment strategies. It also provides evidence to support the implementation of a future prospective clinical trial aimed at evaluating the clinical utility of the SPC test in guiding personalized treatment decisions for gastric cancer patients.

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.

Determining the precise extent of sentinel basins during laparoscopic gastrectomy for early gastric cancer.

PURPOSE: By analyzing sentinel basin dissection (SBD) data from the SEntinel Node ORIented Tailored Approach (SENORITA) trial, we sought to determine the precise extent of the sentinel basin (SB) without a tracer. MATERIALS AND METHODS: This study investigated SB length in patients (n = 25) who underwent laparoscopic SBD for early gastric cancer (EGC) in the SENORITA trial. SB length along the greater curvature (GC) and lesser curvature (LC) was measured intraoperatively before performing SBD. RESULTS: In all 25 cases, along the LC of the stomach, the lengths of the SB were 3.7 cm [2.0-5.0] (median [min-max]) proximally and 3.0 cm [2.3-5.5] distally; along the GC side, the lengths of the SB were 6.8 cm [3.5-11.0] proximally and 7.0 cm [3.8-9.5] distally from the tumors. The SB length at the GC or LC side was not significantly different between subgroups categorized by tumor depth, size, and longitudinal location. When tumors were located at the anterior wall of the stomach, the length of the proximal SB (10.0 cm [9.0-11.0]) at the GC side was the longest. In cases with several sentinel lymph nodes (SLNs), the lengths of the SB at the GC side were significantly longer than those with fewer SLNs. However, the lengths of the SB were similar on the LC side regardless of the number of SLNs. CONCLUSIONS: This pilot study had some limitations of a small number of enrolled patients, the lack of research on the specific station of SLNs, and the inaccurate indication for sentinel node navigation surgery (SNNS) without tracer. Nevertheless, the present study which reported the extents of SBs might be the first step towards simplifying procedures in laparoscopic SNNS for stomach preservation in EGC.

Gastric cancer surgery in South Korea: Past, present, and future.

Gastric cancer remains a significant global health concern and its surgical management approaches have undergone significant changes in South Korea and worldwide. Subtotal or total gastrectomy with D2 lymph node dissection is well established as a standard surgical procedure for gastric cancer. With the active implementation of cancer screening in South Korea, the proportion of early gastric cancer cases has significantly increased over the past few decades, leading to a steady increase in the survival rate among patients. Furthermore, recent advances in surgical instruments and techniques have made minimally invasive surgery increasingly prevalent, not only for early but also for advanced gastric cancer. We aim to provide a comprehensive overview of the evolution and current status of gastric cancer surgery in South Korea.

Efficacy of endoscopic management for anastomotic leakage after gastrectomy in patients with gastric cancer.

BACKGROUND: Anastomotic leakage (AL) after gastrectomy in gastric cancer patients is associated with high mortality rates. Various endoscopic procedures are available to manage this postoperative complication. The aim of study was to evaluate the outcome of two endoscopic modalities, clippings and stents, for the treatment of AL. PATIENTS AND METHODS: There were 4916 gastric cancer patients who underwent gastrectomy between December 2007 and January 2016 at the National Cancer Center, Korea. A total of 115 patients (2.3%) developed AL. Of these, 85 patients (1.7%) received endoscopic therapy for AL and were included in this retrospective study. The endpoints were the complete leakage closure rates and risk factors associated with failure of endoscopic therapy. RESULTS: Of the 85 patients, 62 received endoscopic clippings (with or without detachable snares), and 23 received a stent insertion. Overall, the complete leakage closure rate was 80%, and no significant difference was found between the clipping and stent groups (79.0% vs. 82.6%, respectively; P = 0.89). The complete leakage closure rate was significantly lower in the duodenal and jejunal stump sites (60%) than esophageal sites (86.1%) and gastric sites (94.1%; P = 0.026). The multivariate analysis showed that stump leakage sites (adjusted odds ratio [aOR], 4.51; P = 0.031) and the presence of intra-abdominal abscess (aOR, 4.92; P = -0.025) were associated with unsuccessful leakage closures. CONCLUSIONS: Endoscopic therapy using clippings or stents is an effective method for the postoperative management of AL in gastric cancer patients. This therapy can be considered a primary treatment option due to its demonstrated efficacy, safety, and minimally invasive nature.

Prediction model for curative endoscopic submucosal dissection of undifferentiated-type early gastric cancer.

BACKGROUND: Endoscopic submucosal dissection (ESD) is an effective treatment for early gastric cancer (EGC); however, its curative resection rate is low for undifferentiated-type EGC. We developed and externally validated a prediction model for curative ESD of undifferentiated-type EGC. METHODS: In this cross-sectional study, we included 448 patients who underwent ESD for undifferentiated-type EGC at 18 hospitals in Korea between 2005 and 2015 in the development cohort and 1342 patients who underwent surgery at two hospitals in the validation cohort. A prediction model was developed using the logistic regression model. RESULTS: Endoscopic tumor size 1-2 cm (odds ratio [OR], 2.40; 95% confidence interval [CI] 1.54-3.73), tumor size > 2 cm (OR, 14.00; 95% CI 6.81-28.77), and proximal tumor location from the lower to upper third of the stomach (OR, 1.45; 95% CI 1.03-2.04) were independent predictors of non-curative ESD. A six-score prediction model was developed by assigning points to endoscopic tumor size > 2 cm (five points), tumor size 1-2 cm (two points), upper third location (two points), and middle third location (one point). The rate of curative ESD ranged from 70.6% (score 0) to 11.6% (score 5) with an area under the receiver operating characteristic curve (AUC) of 0.720 (95% CI 0.673-0.766). The model also showed good performance in the validation cohort (AUC, 0.775; 95% CI 0.748-0.803). CONCLUSIONS: This six-score prediction model may help in predicting curative ESD and making informed decisions about the treatment selection between ESD and surgery for undifferentiated-type EGC.

Effectiveness of Intraoperative Endoscopy for Localization of Early Gastric Cancer during Laparoscopic Distal Gastrectomy.

INTRODUCTION: Intraoperative localization of tumors has been considered crucial in determining adequate resection margins during laparoscopic gastrectomy for early gastric cancer (EGC). This study has evaluated the effectiveness of intraoperative endoscopy for localization of EGC during the totally laparoscopic distal gastrectomy. METHODS: Patients with EGC who received totally laparoscopic distal gastrectomy from January 2018 to March 2020 were included in this study. Except the tumors located in the antrum, the patients were categorized into two groups: no localization procedure (n = 144) and intraoperative endoscopy (n = 65). To evaluate the effectiveness of the localization procedure, proximal resection margin (PRM) involvement by the tumor and approximation of optimal PRM were compared, including their postoperative outcomes. RESULTS: There were 3 patients (2.1%) with tumor involvement of the PRM at the initial gastric resection in the no localization group. Distance from the tumor to the PRM was determined to be not significantly different between the no localization group and intraoperative endoscopy group. The PRM distribution pattern and reconstruction method were also not significantly different between the two groups. DISCUSSION/CONCLUSION: Intraoperative endoscopy for localization of EGC is an effective method to avoid tumor involvement at the resection margin during the laparoscopic gastrectomy with intracorporeal gastric resection and reconstruction.

Risks and benefits of additional surgery for early gastric cancer in the upper third of the stomach meeting non-curative resection criteria after endoscopic submucosal dissection.

BACKGROUND: Additional surgery is recommended after non-curative endoscopic submucosal dissection for early gastric cancer. However, it is not easy to recommend for tumors located in the upper third of the stomach, because it would be a total or proximal gastrectomy. This study aimed to evaluate the actual risks and benefits of additional gastrectomy for upper third tumors. METHODS: We reviewed the clinicopathological data of patients who underwent total or proximal gastrectomy for early gastric cancer in the upper third of the stomach between March 2002 and January 2021. The incidence of lymph node metastasis and postoperative complications were calculated, and risk factors for lymph node metastasis were identified using logistic regression analysis. Survival rates were analyzed using the Kaplan-Meier method and log-rank test. RESULTS: A total of 523 patients underwent total or proximal gastrectomy for early gastric cancer; 379 of them had tumors meeting the non-curative resection criteria for endoscopic submucosal dissection. The overall lymph node metastasis rate was 9.5%, and lymphovascular invasion was the only significant risk factor for lymph node metastasis (p < 0.001). The most common sites of lymph node metastasis were stations 1, 3, and 7, with their rates being 3.2%, 3.7%, and 3.2%, respectively. Overall and severe (Clavien-Dindo grade III or higher) postoperative complication rates were 21.1% and 14.0%, respectively, while postoperative mortality was 0.5% (2/379). The 5-year overall survival rates for patients with and without lymph node metastasis were 96.1% and 81.1%, respectively (p = 0.076). CONCLUSIONS: Before planning an additional gastrectomy after non-curative endoscopic resection for the upper third tumor, we should consider both the benefit of the 9.5% curability for lymph node metastasis and the risks of the 21% postoperative complications and 0.5% mortality.

Comprehensive Learning Curve of Robotic Surgery: Discovery From a Multicenter Prospective Trial of Robotic Gastrectomy.

OBJECTIVE: To evaluate the complication-based learning curve and identify learning-associated complications of robotic gastrectomy. SUMMARY BACKGROUND DATA: With the increased popularity of robotic surgery, a sound understanding of the learning curve in the surgical outcome of robotic surgery has taken on great importance. However, a multicenter prospective study analyzing learning-associated morbidity has never been conducted in robotic gastrectomy. METHODS: Data on 502 robotic gastrectomy cases were prospectively collected from 5 surgeons. Risk-adjusted cumulative sum analysis was applied to visualize the learning curve of robotic gastrectomy on operation time and complications. RESULTS: Twenty-five cases, on average, were needed to overcome complications and operation time-learning curve sufficiently to gain proficiency in 3 surgeons. An additional 23 cases were needed to cross the transitional phase to progress from proficiency to mastery. The moderate complication rate (CD ≥ grade II) was 20% in phase 1 (cases 1-25), 10% in phase 2 (cases 26-65), 26.1% in phase 3 (cases 66-88), and 6.4% in phase 4 (cases 89-125) (P < 0.001). Among diverse complications, CD ≥ grade II intra-abdominal bleeding (P < 0.001) and abdominal pain (P = 0.01) were identified as major learning-associated morbidities of robotic gastrectomy. Previous experience on laparoscopic surgery and mode of training influenced progression in the learning curve. CONCLUSIONS: This is the first study suggesting that technical immaturity substantially affects the surgical outcomes of robotic gastrectomy and that robotic gastrectomy is a complex procedure with a significant learning curve that has implications for physician training and credentialing.

Is Splenic Hilar Lymph Node Dissection Without Splenectomy Essential for Proximal Advanced Gastric Cancer?

BACKGROUND: The standard surgery for proximal advanced gastric cancer (PAGC) is total gastrectomy with D2 lymph node dissection (LND). Although prophylactic splenectomy for splenic hilar LND (No. 10) is not recommended due to any survival advantage, prophylactic LND (No. 10) without splenectomy remains controversial. Thus, we aimed to evaluate whether No. 10 LND is essential for patients' survival benefit in PAGC. METHODS: We conducted a retrospective study of 1038 patients with PAGC who underwent total gastrectomy without splenectomy. After adjusting for confounders and propensity score matching (PSM), patients were grouped into Group 1 (D2 LND without splenic hilar LN; n = 288) or Group 2 (D2 LND with splenic hilar LN; n = 288). Variables between the two groups (5-year overall survival [OS] and disease-free survival [DFS]) were compared, as well as in patients with tumors located in the greater curvature and those with Borrmann type IV disease. RESULTS: The 5-year OS and DFS rates after PSM were not significantly different between Groups 1 and 2 (57.3% vs. 62.1%, p = 0.300; 52.8% vs. 59.7%, p = 0.100, respectively). Furthermore, the 5-year OS and DFS rates in patients with greater curvature involvement (54.4% vs. 61.9%, p = 0.500; 50.0% vs. 57.6%, p = 0.400, respectively) and Borrmann type IV disease (23.8% vs. 38.6%, p = 0.400; 16.7% vs. 33.9%, p = 0.200, respectively) after PSM were also not significantly different between the two groups. CONCLUSIONS: Prophylactic splenic hilar LND without splenectomy does not improve long-term survival in PAGC. Therefore, this procedure might not be essential for patients with PAGC as well greater curvature involvement and Borrmann type IV disease.

A comparative study of the short-term operative outcome between intracorporeal and extracorporeal anastomoses during laparoscopic total gastrectomy.

BACKGROUND: Several studies have reported that intracorporeal anastomosis reduces the requirement for the additional incision for anastomosis, resulting in early recovery compared to extracorporeal anastomosis during laparoscopic distal gastrectomy. However, few studies have investigated postoperative outcome after laparoscopic total gastrectomy (LTG). We compared short-term postoperative outcomes between totally laparoscopic total gastrectomy (TLTG) with intracorporeal anastomosis and conventional laparoscopy-assisted total gastrectomy (LATG) with extracorporeal anastomosis for gastric cancer. METHODS: This retrospective case-control study included 202 patients who underwent LTG from January 2012 to June 2019. LATG was performed in the period before July 2015; TLTG was performed in the period after July 2015. Postoperative short-term outcomes and white blood cell (WBC) count, and C-reactive protein (CRP) levels at 1, 3, and 5 days postoperatively were compared between the groups. RESULTS: One hundred ten patients underwent LATG; 92 underwent TLTG. The pathologic stage was significantly higher in the TLTG group (p = 0.010). Intraoperative estimated blood loss was significantly lower in the TLTG group than in the LATG group (median [range]: 100 [50-150] mL versus [vs.] 50 [30-100], p < 0.001). Postoperative hospital stay duration was significantly longer in the TLTG group than in the LATG group (median [range]: 7 [7-9] days vs. 8 [7-11], p < 0.001). WBC count (6.3 109/L ± 1.9 vs. 8.2 ± 2.5, p = 0.004) and CRP levels (8.3 mg/L ± 6.1 vs. 13.3 ± 9.4, p < 0.001) were lower in the LATG group than in the TLTG group. The overall complication rate was higher in the TLTG group than in the LATG group (16.3% vs. 32.6%, p = 0.007). A higher American Society of Anesthesiologist score was the only significant risk factor for postoperative complications. CONCLUSION: Both procedures are feasible, although TLTG has more risk for postoperative complications than LATG. TLTG should be improved to reduce postoperative complications and provide better postoperative outcomes.

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.

Recent updates and current issues of sentinel node navigation surgery for early gastric cancer.

With the increase in the incidence of early gastric cancer (EGC), several endoscopic and laparoscopic approaches, such as endoscopic submucosal dissection and function-preserving gastrectomy, have been accepted as standard treatments. Sentinel node navigation surgery (SNNS) is an ideal surgical option for preservation of most parts of the stomach and consequent maintenance of normal gastric function to improve quality of life in patients with EGC. Although many previous studies and clinical trials have demonstrated the safety and feasibility of the sentinel node concept in gastric cancer, the clinical application of SNNS is debatable. Several issues regarding technical standardization and oncological safety need to be resolved. Recently several studies to resolve these problems are being actively performed, and SNNS might be an important surgical option in the treatment of gastric cancer in the future.

The Suggestion of Revised Criteria for Endoscopic Resection of Differentiated-Type Submucosal Gastric Cancer.

BACKGROUND: Early gastric cancer that meets the expanded criteria for endoscopic resection (ER) is expected to be associated with a negligible risk for lymph node metastasis (LNM); however, recent studies have reported LNM in submucosal gastric cancer patients who met the existing criteria. In this study, we develop the revised criteria for ER of submucosal gastric cancer with the aim of minimizing LNM. METHODS: We analyzed the clinicopathological data of 2461 patients diagnosed with differentiated, submucosal gastric cancer who underwent surgery at three tertiary hospitals between March 2001 and December 2012, and re-analyzed the pathological slides of all patients. The depth of submucosal invasion was measured histopathologically in two different ways (the classic and alternative methods) to obtain accurate data. RESULTS: Of the enrolled subjects, 306 (17.0%) had LNM. The width of submucosal invasion correlated well with the LNM. We defined the depth and width of submucosal infiltration associated with the lowest incidence of LNM. None of the 254 subjects developed LNM when the following criteria were met: tumor diameter ≤ 3 cm, submucosal invasion depth < 1000 µm (as measured using the alternative method), submucosal invasion width < 4 mm, no lymphovascular invasion, and no perineural invasion; however, LNM was observed in 2.7% of subjects (6/218) who met the existing criteria. CONCLUSIONS: We revised the criteria for ER by adopting the alternative method to measure the depth of submucosal invasion and adding the width of such invasion. Our criteria better predicted LNM than the current criteria used to select ER to treat submucosal gastric cancer.

Nomogram to predict lymph node metastasis in patients with early gastric cancer: a useful clinical tool to reduce gastrectomy after endoscopic resection.

BACKGROUND: The indications for endoscopic dissection have been expanded to improve the quality of life of patients with early gastric cancer (EGC). This study aimed to develop a nomogram to predict the status of lymph node metastasis with the aim of avoiding unnecessary gastrectomies. METHODS: We reviewed the clinicopathological data of 10 579 patients who underwent curative resection for EGC. The nomogram was developed by multivariate analysis and was evaluated by external validation. Overall, disease-free and recurrence-free survival were compared between the gastrectomy group of 6641 patients and the endoscopic dissection group of 999 patients to show the efficacy of the nomogram. RESULTS: Multivariate analyses revealed that age, tumor size, lymphatic invasion, depth of invasion, and histologic differentiation were all significant prognostic factors for lymph node metastasis. The nomogram had good discriminatory performance, with a concordance index of 0.846. This was supported by the external validation point of 0.813. For patients with low risk of lymph node metastasis on the nomogram (≤ 3 % of the provisional value in this study), the endoscopic dissection and gastrectomy groups had comparable rates of overall (P = 0.32), disease-free (P = 0.47), and recurrence-free (P = 0.09) survival. CONCLUSIONS: We developed and validated a nomogram that predicts the risk of lymph node metastasis in EGC based on a large database. This precision nomogram is useful to avoid unnecessary gastrectomy after endoscopic dissection, which may ultimately improve the quality of life of patients with EGC.