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.

Clinical characteristics and outcomes of Clostridioides difficile infection in the intensive care unit: a KASID multi-centre study

BACKGROUND

Despite the growing clinical and economic burden of Clostridioides difficile infection (CDI), data on CDI in the intensive care unit (ICU) in the Asia-Pacific region are lacking.

METHODS

This retrospective study analysed 191 patients who were treated with CDI in the ICUs of three hospitals in South Korea from January 2017 to May 2021. Backward-stepwise multiple logistic regression was used to identify factors influencing the treatment response and mortality.

RESULTS

Fifty-eight patients (30.4%) were considered immunocompromised. The mean Charlson comorbidity index was 5.65 ± 2.39 (10-year survival rate: 21%), the APACHE II score was 20.86 ± 7.78 (mortality rate: 40%), the ATLAS score was 5.45 ± 1.59 (cure rate: 75%), and the SOFA score was 7.97 ± 4.03 (mortality rate: 21.5%). Fifty-eight (30.4%) of the CDI cases were severe and 40 (20.9%) were fulminant. Oral vancomycin or oral metronidazole was the most frequently first-line treatments (N = 57; 32.6%). The 10-day response rate was 59.7% and the eight-week overall mortality rate was 41.4%. Fulminant CDI (OR 0.230; 95% CI 0.085-0.623) and each one-unit increment in the SOFA score (OR 0.848; 95% CI 0.759-0.947) were associated with treatment failure. High APACHE II (OR 0.355; 95% CI 0.143-0.880) and SOFA (OR 0.164; 95% CI 0.061-0.441) scores were associated with higher mortality.

CONCLUSIONS

High-risk patients in the ICU had a higher mortality rate and a lower cure rate of CDI. Further research is required to provide more accurate prediction scoring systems and better clinical outcomes.

Induction Motor Fault Diagnosis Using Support Vector Machine, Neural Networks, and Boosting Methods

Induction motors are robust and cost effective; thus, they are commonly used as power sources in various industrial applications. However, due to the characteristics of induction motors, industrial processes can stop when motor failures occur. Thus, research is required to realize the quick and accurate diagnosis of faults in induction motors. In this study, we constructed an induction motor simulator with normal, rotor failure, and bearing failure states. Using this simulator, 1240 vibration datasets comprising 1024 data samples were obtained for each state. Then, failure diagnosis was performed on the acquired data using support vector machine, multilayer neural network, convolutional neural network, gradient boosting machine, and XGBoost machine learning models. The diagnostic accuracies and calculation speeds of these models were verified via stratified K-fold cross validation. In addition, a graphical user interface was designed and implemented for the proposed fault diagnosis technique. The experimental results demonstrate that the proposed fault diagnosis technique is suitable for diagnosing faults in induction motors.

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

Question

What is the oncologic safety profile of laparoscopic distal gastrectomy for the treatment of clinically advanced gastric cancer in terms of 5-year survival?

Findings

In this randomized clinical trial of 1050 patients, in patients who underwent laparoscopic or open distal gastrectomy, the 5-year overall survival rates (88.9% vs 88.7%) and relapse-free survival rates (79.5% vs 81.1%) did not differ significantly. The late complication rate was significantly lower in the laparoscopic group than in the open group (6.5% vs 11.0%).

Meaning

The 5-year follow-up results of the Korean Laparoendoscopic Gastrointestinal Surgery Study (KLASS)-02 trial support the rationale for laparoscopic surgery in patients with locally advanced gastric cancer.

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

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 ± 1.71 vs 0.99 ± 1.54, P = .015) and the maximal size (3.53 ± 6.14 vs 2.08 ± 2.88, 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.

The 2019-2020 EURADOS WG10 and RENEB Field Test of Retrospective Dosimetry Methods in a Small-Scale Incident Involving Ionizing Radiation

With the use of ionizing radiation comes the risk of accidents and malevolent misuse. When unplanned exposures occur, there are several methods which can be used to retrospectively reconstruct individual radiation exposures; biological methods include analysis of aberrations and damage of chromosomes and DNA, while physical methods rely on luminescence (TL/OSL) or EPR signals. To ensure the quality and dependability of these methods, they should be evaluated under realistic exposure conditions. In 2019, EURADOS Working Group 10 and RENEB organized a field test with the purpose of evaluating retrospective dosimetry methods as carried out in potential real-life exposure scenarios. A 1.36 TBq 192Ir source was used to irradiate anthropomorphic phantoms in different geometries at doses of several Gy in an outdoor open-air geometry. Materials intended for accident dosimetry (including mobile phones and blood) were placed on the phantoms together with reference dosimeters (LiF, NaCl, glass). The objective was to estimate radiation exposures received by individuals as measured using blood and fortuitous materials, and to evaluate these methods by comparing the estimated doses to reference measurements and Monte Carlo simulations. Herein we describe the overall planning, goals, execution and preliminary outcomes of the 2019 field test. Such field tests are essential for the development of new and existing methods. The outputs from this field test include useful experience in terms of planning and execution of future exercises, with respect to time management, radiation protection, and reference dosimetry to be considered to obtain relevant data for analysis.

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.

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.

A feasibility study of laparoscopic total gastrectomy for clinical stage I gastric cancer: a prospective multi-center phase II clinical trial, KLASS 03

BACKGROUND

With improved short-term surgical outcomes, laparoscopic distal gastrectomy has rapidly gained popularity. However, the safety and feasibility of laparoscopic total gastrectomy (LTG) has not yet been proven due to the difficulty of the technique. This single-arm prospective multi-center study was conducted to evaluate the use of LTG for clinical stage I gastric cancer.

METHODS

Between October 2012 and January 2014, 170 patients with pathologically proven, clinical stage I gastric adenocarcinoma located at the proximal stomach were enrolled. Twenty-two experienced surgeons from 19 institutions participated in this clinical trial. The primary end point was the incidence of postoperative morbidity and mortality at postoperative 30 days. The severity of postoperative complications was categorized according to Clavien-Dindo classification, and the incidence of postoperative morbidity and mortality was compared with that in a historical control.

RESULTS

Of the enrolled patients, 160 met criteria for inclusion in the full analysis set. Postoperative morbidity and mortality rates reached 20.6% (33/160) and 0.6% (1/160), respectively. Fifteen patients (9.4%) had grade III or higher complications, and three reoperations (1.9%) were performed. The incidence of morbidity after LTG in this trial did not significantly differ from that reported in a previous study for open total gastrectomy (18%).

CONCLUSIONS

LTG performed by experienced surgeons showed acceptable postoperative morbidity and mortality for patients with clinical stage I gastric cancer.

Risk Factors for the Development of Incisional Hernia in Mini-laparotomy Wounds Following Laparoscopic Distal Gastrectomy in Patients with Gastric Cancer

Purpose

To determine the incidence of incisional hernia (IH) in mini-laparotomy wounds and analyze the risk factors of IH following laparoscopic distal gastrectomy in patients with gastric cancer.

Materials and Methods

A total of 565 patients who underwent laparoscopic distal gastrectomy for gastric cancer at Dong-A University Hospital, Busan, South Korea, between June 2010 and December 2015, were enrolled. IH was diagnosed through physical examination or computed tomography imaging. Incidence rate and risk factors of IH were evaluated through a long-term follow-up.

Results

Of those enrolled, 16 patients (2.8%) developed IH. The median duration of follow-up was 58 months (range, 25–90 months). Of the 16 patients with IH, 15 (93.7%) were diagnosed within 12 months postoperatively. Multivariate analysis showed that female sex (odds ratio [OR], 3.869; 95% confidence interval [CI], 1.325–11.296), higher body mass index (BMI; OR, 1.229; 95% CI, 1.048–1.422), and presence of comorbidity (OR, 3.806; 95% CI, 1.212–11.948) were significant risk factors of IH. The vast majority of IH cases (15/16 patients, 93.7%) developed in the totally laparoscopic distal gastrectomy (TLDG) group. However, the type of surgery (i.e., TLDG or laparoscopy-assisted distal gastrectomy) did not significantly affect the development of IH (P=0.060).

Conclusions

A median follow-up of 58 months showed that the overall incidence of IH in mini-laparotomy wounds was 2.8%. Multivariate analysis showed that female sex, higher BMI, and presence of comorbidity were significant risk factors of IH. Thus, surgeons should monitor the closure of mini-laparotomy wounds in patients with risk factors of IH undergoing laparoscopic distal gastrectomy.

Characterization of antimicrobial resistance and quinolone resistance factors in high-level ciprofloxacin-resistant Enterococcus faecalis and Enterococcus faecium isolates obtained from fresh produce and fecal samples of patients

BACKGROUND

The emergence of fluoroquinolone-resistant enterococci is worldwide. Antimicrobial resistance was characterized and the effect of quinolone-resistance factors was analyzed in high-level ciprofloxacin-resistant (HLCR) Enterococcus faecalis and Enterococcus faecium isolated from fresh produce and fecal samples of patients.

RESULTS

Among the 81 ciprofloxacin-resistant Enterococcus isolates, 46 showed high levels of ciprofloxacin resistance, resistance to other quinolone antibiotics, and multidrug resistance profiles. The virulence factors esp and hyl were identified in 27 (58.7%) and 25 (54.3%) of isolates, respectively. Sequence type analysis showed that 35 strains of HLCR E. faecium were clonal complex 17. Eleven strains of HLCR E. faecalis were confirmed as sequence type (ST) 28, ST 64 and ST 125. Quinolone resistance-determining region mutation was identified in HLCR Enterococcus isolates; with serine being changed in gyrA83, gyrA87 and parC80. This result shows that gyrA and parC mutations could be important factors for high-level resistance to fluoroquinolones.

CONCLUSION

No significant differences were observed in antimicrobial resistance patterns and genetic characteristics among the isolates from fresh produce and fecal samples. Therefore, good agricultural practices in farming and continuous monitoring of patients, food and the environment for Enterococcus spp. should be performed to prevent antimicrobial resistance and enable reduction of resistance rates. © 2016 Society of Chemical Industry.

Characterization of Vancomycin-Resistant Enterococcus faecalis and Enterococcus faecium Isolated from Fresh Produces and Human Fecal Samples

Increased enterococcal infections in hospitals and multidrug-resistant and vancomycin-resistant enterococci (VRE) isolated from humans, animals, and food sources raised public health concern on the presence of VRE in multiple sources. We performed a comparative analysis of the antimicrobial resistance and genetics of VRE isolates derived from fresh produce and human fecal samples. Of 389 Enterococcus isolates, 8 fecal and 3 produce isolates were resistant to vancomycin and teicoplanin; all harbored vanA gene. The VRE isolates showed multidrug-resistant properties. The isolates from fresh produce in this study showed to have the common shared characteristics with the isolates from humans by the results of antimicrobial resistance, multilocus sequence typing, and Tn 1546 transposon analysis. Therefore, VRE isolates from fresh produce are likely related to VRE derived from humans. The results suggested that VRE may contaminate vegetables through the environment, and the contaminated vegetables could then act as a vehicle for human infections. Ongoing nationwide surveillance of antibiotic resistance and the promotion of the proper use of antibiotics are necessary.

Who may benefit from robotic gastrectomy?: A subgroup analysis of multicenter prospective comparative study data on robotic versus laparoscopic gastrectomy

AIMS

Robotic gastrectomy for gastric cancer has been proven to be a feasible and safe minimally invasive procedure. However, our previous multicenter prospective study indicated that robotic gastrectomy is not superior to laparoscopic gastrectomy. This study aimed to identify which subgroups of patients would benefit from robotic gastrectomy rather than from conventional laparoscopic gastrectomy.

METHODS

A prospective multicenter comparative study comparing laparoscopic and robotic gastrectomy was previously conducted. We divided the patients into subgroups according to obesity, type of gastrectomy performed, and extent of lymph node dissection. Surgical outcomes were compared between the robotic and laparoscopic groups in each subgroup.

RESULTS

A total of 434 patients were enrolled into the robotic (n = 223) and laparoscopic (n = 211) surgery groups. According to obesity and gastrectomy type, there was no difference in the estimated blood loss (EBL), number of retrieved lymph nodes, complication rate, open conversion rate, and the length of hospital stay between the robotic and laparoscopic groups. According to the extent of lymph node dissection, the robotic group showed a significantly lower EBL than did the laparoscopic group after D2 dissection (P = 0.021), while there was no difference in EBL in patients that did not undergo D2 dissection (P = 0.365).

CONCLUSION

Patients with gastric cancer undergoing D2 lymph node dissection can benefit from less blood loss when a robotic surgery system is used.

Long-Term Surgical Outcome of 1057 Gastric GISTs According to 7th UICC/AJCC TNM System: Multicenter Observational Study From Korea and Japan

The aim of this study was to evaluate the treatment and prognosis of gastric gastrointestinal stromal tumors (GISTs) according to the 7th UICC/AJCC tumor-node-metastasis (TNM) system and the modified National Institutes of Health (NIH) risk classification. The study cohort consisted of 1057 patients with gastric GIST who underwent surgery between January 2000 and December 2007 from 13 institutions in Korea and 2 in Japan. Clinicopathologic characteristics, surgical outcomes, recurrence, and 5-year recurrence-free survival were evaluated.The mean age of the patients was 58.6 years. Thirty patients (2.8%) had distant metastasis preoperatively. Median tumor size was 4.0 cm. Complete resection (R0 resection) was achieved in 1018 patients (96.3%). Eighty-six patients (8.1%) had postoperative complications, and 2 patients (0.2%) died within 30 days after surgery. According to the 7th UICC/AJCC TNM system, 5-year recurrence-free survival rates were 95% to 99% in stage I, 94.1% in stage II, 74.1% in stage IIIA, 48.6% in stage IIIB, and 50.0% in stage IV patients. On survival analysis of high-risk patients according to the TNM system, the 5-year recurrence-free survival rates were 91.6% in stage II, 74.1% in stage IIIA, and 48.6% in stage IIIB patients. Independent factors of recurrence following surgery for gastric GIST were gender, tumor size, mitotic count, and radicality on multivariate analysis.The treatment outcome and prognosis of gastric GIST in Korea and Japan seem more favorable compared to those in Western countries. Compared to the modified NIH risk classification, the 7th UICC/AJCC TNM system is more reflective of the 5-year recurrence-free survival of patients with gastric GIST.

Effect of visceral fat area on outcomes of laparoscopyassisted distal gastrectomy for gastric cancer: subgroup analysis by gender and parameters of obesity

PURPOSE

The aim of this study was to investigate the impact of the visceral fat area (VFA) of patients with gastric cancer undergoing laparoscopic surgery on operative outcomes such as number of retrieved lymph nodes (LNs) and operative time.

METHODS

We retrospectively reviewed the medical records and the CT scans of 597 patients with gastric cancer who underwent laparoscopy assisted distal gastrectomy (LADG) with partial omentectomy and LN dissection (>D1 plus beta). Patients were stratified by gender, VFA, and body mass index (BMI), and the clinicopathologic characteristics and operative outcomes were evaluated. Multiple linear regression analysis was used to assess the effects of VFA and BMI on the number of retrieved LNs and operative time in male and female patients.

RESULTS

The mean number of retrieved LNs was significantly decreased for both male and female patients with high VFA. The operative time was significantly longer for both male and female patients with high VFA. The number of retrieved LNs had a statistically significant negative correlation with VFA in both men and women, but not with BMI. The operative time had a statistically significant positive correlation with VFA in men, whereas the operative time had a statistically significant positive correlation with BMI in women.

CONCLUSION

The preoperative VFA of male patients with gastric cancer who undergo LADG may affect the number of retrieved LNs and operative time. VFA was more useful than BMI for predicting outcomes of LADG.

Morbidity and mortality after laparoscopy-assisted and open distal gastrectomy for stage I gastric cancer: Results from a multicenter randomized controlled trial (KLASS-01)

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Background: Laparoscopy assisted distal gastrectomy (LADG) is widely performed for gastric cancer in Eastern countries, although large scale prospective data are still lacking. We conducted a phase III, multicenter randomized controlled trial (KLASS-01) to compare the short and long term outcomes of LADG versus open distal gastrectomy (ODG) in patients with clinical stage I gastric cancer in Korea. Methods: The primary end point was 5-year overall survival. The morbidity within 30 postoperative days and the surgical mortality were compared to evaluate the safety of LADG as a secondary end point. A total of 1,416 patients were randomly assigned to the LADG group (n = 705) or the ODG group (n = 711) between Feb 1, 2006 and Aug 31, 2010. Results: 1,256 were eligible for per protocol (PP) analysis (644 and 612, respectively). The overall complication rate was significantly lower in the LADG group (LADG vs. ODG; 13.0% vs. 19.9%, P =.001). In detail, the wound complication rate of the LADG group was significantly lower than that of the ODG group (3.1% vs. 7.7%, P <.001). The major intra-abdominal complication (7.6% vs. 10.3%, P =.095) and mortality rates (0.6% vs. 0.3%, P =.450) were similar between groups. Modified intention-to-treat analysis showed similar results with PP analysis. Conclusions: LADG for patients with clinical stage I gastric cancer is safe and has a benefit of lower occurrence of wound complication compared with conventional ODG. Clinical trial information: NCT00452751.

Signet ring cell histology is not an independent predictor of poor prognosis after curative resection for gastric cancer: a propensity analysis by the KLASS Group

Whether signet ring cell (SRC) histology carries a worse prognosis than other forms of gastric adenocarcinoma has been questioned. The present study investigated the differences in clinicopathologic features and survival between SRC and non-SRC adenocarcinoma. The prospectively collected data of 2643 patients who had undergone curative gastrectomy between 1998 and 2005 by 10 surgeons were reviewed. Additionally, we employed analysis of covariance, propensity-score risk adjustment, and propensity-based matching to account for possible selection bias. The baseline characteristics of prematched patients with SRC or non-SRC adenocarcinoma histology differed: SRC presented in younger patients and less often in men, was more likely found in the middle stomach, and was more likely to be Stage I. After applying the propensity-score strata and propensity-score matching, there was no difference in the baseline characteristics, and SRC was not an independent risk factor for mortality in the same stage. SRC is not an independent predictor of poor prognosis after curative resection for gastric cancer in Korea.

How much progress has been made in minimally invasive surgery for gastric cancer in Korea?: a viewpoint from Korean prospective clinical trials

Gastric cancer is the most common cancer in Korea. Because the incidence of gastric cancer is still high even with early detection and because of developments in surgical instruments and technological advances, minimally invasive surgery has rapidly become an accepted treatment for gastric cancer in Korea. Many Korean gastric surgeons have contributed to the rapid adaptation of minimally invasive surgery for gastric cancer: not only the Korean Laparoscopic Gastrointestinal Surgery Study (KLASS) group, but also other expert surgeons after the 2000s. Thanks to their vigorous efforts involving active learning, education, workshops, academic communications, and international communications with active laparoscopic gastric surgeons in Korea, numerous results and well-designed large-scale clinical studies have been published or are actively ongoing, thus increasing its wide acceptance as an option for gastric cancer. Now, Korea has become one of the leading countries using minimally invasive surgery for the treatment of gastric cancer. This review article will summarize the current status and issues, as well as the clinical trials that have finished or are ongoing, regarding minimally invasive surgery for gastric cancer in Korea.

The differences in clinicopathological features and prognosis among the subtypes of signet ring cell, mucinous, papillary, and lymphoepithelioma-like carcinoma in advanced gastric cancer

BACKGROUND/AIMS

There are differing histologic subtypes of gastric cancer. We investigated the clinicopathological features and prognosis of: signet ring cell (SRC), mucinous (MGC), papillary (PGC), and lymphoepithelioma-like (LELC) carcinoma in advanced gastric cancer.

METHODOLOGY

One hundred thirty six advanced gastric cancer patients, including 62 SRCs, 43 MGCs, 9 PGCs, and 22 LELCs, who underwent R0 gastrectomy between 2002 and 2013, were retrospectively evaluated.

RESULTS

There were significant differences in several clinicopathological features. There were found to be statistical differences in postoperative outcomes in the type of gastrectomy and type of anastomosis (p<0.001 and p<0.001, respectively). In terms of overall survival analysis, there was no statistical survival difference among the subtypes of advanced gastric cancer (p=0.088). However, LELC had a better prognosis than the other groups.

CONCLUSIONS

There were some differences in several of the clinicopathological features of the subtypes advanced gastric cancer. Although there were no statistical differences in survival, those with LELC showed a better prognosis than did the other groups. Therefore, the treatment of advanced gastric cancer should be individualized, and prognosis considered, according to the subtype.

Risk factors for duodenal stump leakage after gastrectomy for gastric cancer and management technique of stump leakage

BACKGROUND/AIMS

The goal of this study was to elucidate the risk factors for duodenal stump leakage after gastrectomy for gastric cancer. In addition, the management of duodenal stump leakage is reviewed.

METHODOLOGY

From January 2002 through December 2012, 1,195 patients with gastric cancer who underwent gastric R0 resection were enrolled in this study. The clinicopathologic features, postoperative outcomes (i.e., operation time, hospital stay, surgical procedures, method of duodenal stump closure, retrieved lymph nodes), and the risk factors of duodenal stump leakage were analyzed.

RESULTS

Of the 1,195 patients, 13 patients (1.1%) suffered duodenal stump leakage. Most of the patients with duodenal stump leakage were male (92.3%). Nine patients underwent a subtotal gastrectomy with Billroth- II or Roux-en-Y anastomosis; the other four patients underwent a total gastrectomy with a Roux-en-Y anastomosis. There were two mortalities. With univariate and multivariate analysis, age was the most predictable factor for duodenal stump leakage (p= 0.034, p=0.044) CONCLUSIONS: Duodenal stump leakage was affected by the age. For older patients who undergo a radical gastrectomy for gastric cancer, the surgeon must pay meticulous attention to the transection and mobilization of the duodenum in order to prevent duodenal stump leakage.

Comprehension of readmission after laparoscopy assisted distal gastrectomy: what are the causes?

Purpose

The aim of this study is to evaluate long-term outcomes regarding readmission for laparoscopy-assisted distal subtotal gastrectomy (LADG) compared to conventional open distal subtotal gastrectomy (CODG) for early gastric cancer (EGC).

Methods

Between January 2003 and December 2006, 223 and 106 patients underwent LADG and CODG, respectively, for EGC by one surgeon. The clinicopathologic characteristics, postoperative outcomes, postoperative complications, overall 5-year survival, recurrence, and readmission were retrospectively compared between the two groups.

Results

Multiple readmission rate in LADG was significantly less than that in CODG (0.4% vs. 3.8%, P = 0.039), although the readmission rate, reoperation rate after discharge, and mean readmission days were not significantly different between the two groups. Readmission rates of the LADG and CODG groups were 12.6% and 14.2%, respectively. First flatus time and postoperative hospital stay was significantly shorter in the LADG group. However, there was no significant difference in the complication rates between the two groups. Overall 5-year survival rates of the LADG and CODG group were 100% and 99.1% (P = 0.038), respectively.

Conclusion

Compared to the CODG group, the LADG group has several advantages in surgical short-term outcome and some benefit in terms of readmission in surgical long-term outcome for patients with EGC, even though the oncologic outcome of LADG is similar to that of CODG over 5 years.

Is the rate of postoperative complications following laparoscopy-assisted gastrectomy higher in elderly patients than in younger patients?

Background

With an increase in life expectancy, very elderly patients are presenting with gastric cancer more commonly than ever. The present study retrospectively analyzed the surgical outcomes of laparoscopy-assisted gastrectomy for gastric cancer in the young, elderly, and very elderly age groups.

Methods

The study group consisted of 1,055 patients who underwent laparoscopy-assisted gastrectomy between February 2002 and December 2012. We divided these patients into three groups; group 1 (young age, <65 years), group 2 (elderly age, 65–74 years), and group 3 (very elderly age, ≥75 years).

Results

There were statistical differences in the rates of postoperative complications among the three groups (P = 0.008). However, when assessed according to the severity of postoperative complications based on the Clavien-Dindo classification, there was no statistical difference among the three groups (P = 0.562).

Conclusions

Laparoscopy-assisted gastrectomy for gastric cancer can be performed in very elderly patients. In analyzing studies of elderly patients with postoperative complications following the procedure, not only should the rate of postoperative complications be taken into consideration, but also the severity of any postoperative complications.

Analysis of prognostic factors and outcomes of gastric cancer in younger patients: A case control study using propensity score methods

AIM: To understand the clinicopathological and prognostic features of gastric cancer in younger and older patients.

METHODS: Between January 2002 and December 2008, 1667 patients underwent curative gastric surgery. For comparative purposes, the patients were divided into two groups: younger patients who were less than 40 years old (112 patients), and older patients who were 40 years old and older (1555 patients). In both groups, propensity scoring methods were used to select patients with similar disease statuses. A total of 224 matched cases, with 112 patients in each group, were included in the final analysis.

RESULTS: Compared to the older group, the younger group with gastric cancer had a significantly higher percentage of females (P = 0.007), poorly differentiated or signet ring cell carcinoma (P < 0.001), advanced T stage gastric cancer (P = 0.045), and advanced tumor-node-metastasis stage cancer (P = 0.036). The older group with gastric cancer had more comorbidities (P < 0.001). With the exception of the number of lymph node dissection (P < 0.001) and retrieved lymph node (P = 0.010), there were no statistically significant differences between the postoperative outcomes of the two groups. During the follow-up period, there were 19 recurrences in the younger group and 11 recurrences in the older group. The overall five-year survival rates in the younger and older groups were 84.3% and 89.6%, respectively (P = 0.172). There were no significant differences (P = 0.238) in the overall survival of patients with advanced T stage gastric cancer in the two groups, with five-year survival rates of 70.8% in the younger group and 79.5% in the older group. With regard to the age-adjusted survival rate, there was significant difference between the two groups (P = 0.225).

CONCLUSION: In spite of aggressive cancer patterns in the younger group with gastric cancer, the younger group did not have a worse prognosis than the older group in our study.

Standardization of D2 lymphadenectomy and surgical quality control (KLASS-02-QC): a prospective, observational, multicenter study [NCT01283893]

BACKGROUND

Extended systemic lymphadenectomy (D2) is standard procedure for surgical treatment of advanced gastric cancer (AGC) although less extensive lymphadenectomy (D1) can be applied to early gastric cancer. Complete D2 lymphadenectomy is the mandatory procedure for studies that evaluate surgical treatment results of AGC. However, the actual extent of D2 lymphadenectomy varies among surgeons because of a lacking consensus on the anatomical definition of each lymph node station. This study is aimed to develop a consensus for D2 lymphadenectomy and also to qualify surgeons that can perform both laparoscopic and open D2 gastrectomy.

METHODS/DESIGN

This (KLASS-02-QC) is a prospective, observational, multicenter study to qualify the surgeons that will participate in the KLASS-02-RCT, which is a prospective, randomized, clinical trial comparing laparoscopic and open gastrectomy for AGC. Surgeons and reviewers participating in the study will be required to complete a questionnaire detailing their professional experience and specific gastrectomy surgical background/training, and the gastrectomy metrics of their primary hospitals. All surgeons must submit three laparoscopic and three open D2 gastrectomy videos, respectively. Each video will be allocated to five peer reviewers; thus each surgeon's operations will be assessed by a total of 30 reviews. Based on blinded assessment of unedited videos by experts' review, a separate review evaluation committee will decide whether or not the evaluated surgeon will participate in the KLASS-02-RCT. The primary outcome measure is each surgeon's proficiency, as assessed by the reviewers based on evaluation criteria for completeness of D2 lymphadenectomy.

DISCUSSION

We believe that our study for standardization of D2 lymphadenectomy and surgical quality control (KLASS-02-QC) will guarantee successful implementation of the subsequent KLASS-02-RCT study. After making consensus on D2 lymphadenectomy, we developed evaluation criteria for completeness of D2 lymphadenectomy. We also developed a unique surgical standardization and quality control system that consists of recording unedited surgical videos, and expert review according to evaluation criteria for completeness of D2 lymphadenectomy. We hope our systematic approach will set a milestone in surgical standardization that is essential for surgical clinical trials. Additionally, our methods will serve as a novel system for educating surgeons and assessing surgical proficiency.

TRIAL REGISTRATION

NCT01283893.

Long-term results of laparoscopic gastrectomy for gastric cancer: a large-scale case-control and case-matched Korean multicenter study

PURPOSE

The oncologic outcomes of laparoscopy-assisted gastrectomy for the treatment of gastric cancer have not been evaluated. The aim of this study is to validate the efficacy and safety of laparoscopic gastrectomy for gastric cancer in terms of long-term survival, morbidity, and mortality retrospectively.

PATIENTS AND METHODS

The study group comprised 2,976 patients who were treated with curative intent either by laparoscopic gastrectomy (1,477 patients) or open gastrectomy (1,499 patients) between April 1998 and December 2005. The long-term 5-year actual survival analysis in case-control and case-matched population was conducted using the Kaplan-Meier method. The morbidity and mortality and learning curves were evaluated.

RESULTS

In the case-control study, the overall survival, disease-specific survival, and recurrence-free survival (median follow-up period, 70.8 months) were not statistically different at each cancer stage with the exception of an increased overall survival rate for patients with stage IA cancer treated via laparoscopy (laparoscopic group; 95.3%, open group: 90.3%; P < .001). After matching using a propensity scoring system, the overall survival, disease-specific survival, and recurrence-free survival rates were not statistically different at each stage. The morbidity of the case-matched group was 15.1% in the open group and 12.5% in the laparoscopic group, which also had no statistical significance (P = .184). The mortality rate was also not statistically significant (0.3% in the open group and 0.5% in the laparoscopic group; P = 1.000). The mean learning curve was 42.

CONCLUSION

The long-term oncologic outcomes of laparoscopic gastrectomy for patients with gastric cancer were comparable to those of open gastrectomy in a large-scale, multicenter, retrospective clinical study.

Readmissions following elective radical total gastrectomy for early gastric cancer: a case-controlled study

BACKGROUND

Readmission after gastrectomy is one of the factors that reflect quality of life. Therefore, we analyzed the several factors related to readmissions after total gastrectomy for early gastric cancer.

METHODS

From January 2002 through December 2009, 102 consecutive patients who underwent radical total gastrectomy for early gastric cancer were enrolled in this study. We evaluated the incidence, cause, time point, and type of treatment for readmission after discharge; we compared the readmission and non-readmission groups in regard to clinicopathologic features and postoperative outcomes.

RESULTS

The readmission rate during the five years after total gastrectomy was 22 of 102 (21.6%). The most common cause for readmission was esophagojejunostomy stricture (5 cases). The treatment given for 31 readmissions included 23 conservative therapies, 3 radiologic or endoscopic interventions, and 5 re-operations. No significant differences were detected in the clinicopathologic feature, postoperative outcomes, or 5-year survival rates between the readmission and non-readmission group. No specific risk factor was found to be associated with readmission.

CONCLUSION

Although we could not determine a specific risk factor associated with readmission after radical total gastrectomy, prevention of readmission by evaluating the causes and treatments after radical total gastrectomy can improve the patient's quality of life.

Prospective randomized controlled trial (phase III) to comparing laparoscopic distal gastrectomy with open distal gastrectomy for gastric adenocarcinoma (KLASS 01)

A randomized controlled trial to evaluate the long-term outcomes of laparoscopic distal gastrectomy for gastric cancer is currently ongoing in Korea. Patients with cT1N0M0-cT2aN0M0 (American Joint Committee on Cancer, 6th edition) distal gastric cancer were randomized to receive either laparoscopic or open distal gastrectomy. For surgical quality control, the surgeons participating in this trial had to have performed at least 50 cases each of laparoscopy-assisted distal gastrectomy and open distal gastrectomy and their institutions should have performed more than 80 cases each of both procedures each year. Fifteen surgeons from 12 institutions recruited 1,415 patients. The primary endpoint is overall survival. The secondary endpoints are disease-free survival, morbidity, mortality, quality of life, inflammatory and immune responses, and cost-effectiveness (ClinicalTrials.gov ID: NCT00452751).

Long term survival results for gastric GIST: is laparoscopic surgery for large gastric GIST feasible?

Background

Recently, laparoscopic resection for relatively small sized gastric gastrointestinal stromal tumors (GISTs) has been widely accepted as minimally invasive surgery. However, no report on the long-term safety and efficacy of this surgery for large sized gastric GISTs has been published to date.

Methods

Between July 1998 and January 2011, 104 consecutive patients who underwent resection for gastric GISTs were enrolled in this retrospective study. We assessed the clinicopathological characteristics, postoperative outcomes, patient survival, and tumor recurrence.

Results

Of the 104 patients with gastric GISTs who were included in the study, there were 47 males and 57 females whose mean age was 59.8 years. Sixty-four patients (61.5%) had symptoms associated with tumor. Ten patients included in the group 1, 49 in the group 2, 15 in the group 3a, 9 in the group 5, 14 in the group 6a, and 7 in the group 6b. There was one minor complication and no mortalities. Recurrence was noted in 5 patients, with a median follow-up period of 49.3 months (range, 8.4 to 164.4). The 5-year overall and disease free survival rates of 104 patients were 98.6% and 94.8%, respectively. When comparing large tumor (5–10 cm) between laparoscopic and open surgery, there were statistically differences in age, tumor size, tumor location, and length of hospitalization. There were no statistical differences in the 5-year survival rate between laparoscopic and open surgery for large tumor (5-10cm).

Conclusion

Laparoscopic surgery is feasible and effective as an oncologic treatment of gastric GISTs. Moreover, laparoscopic surgery can be an acceptable alternative to open methods for gastric GISTs of size bigger than 5 cm.

Comparative study of laparoscopy-assisted versus open subtotal gastrectomy for pT2 gastric cancer

PURPOSE

Laparoscopy-assisted distal gastrectomy (LADG) is a widely accepted surgery for early gastric cancer. However, its use in advanced gastric cancer has rarely been studied. The aim of this study is to investigate the feasibility and survival outcomes of LADG for pT2 gastric cancer.

MATERIALS AND METHODS

Between January 2004 and December 2009, we evaluated 67 and 52 patients who underwent open distal gastrectomy (ODG) and LADG, respectively, with diagnosis of pT2 gastric cancer. The clinicopathological characteristics, postoperative outcomes, and survival were retrospectively compared between the two groups.

RESULTS

There were statistically significant differences in the proximal margin of the clinicopathological parameters. The operation time was significantly longer in LADG than in ODG (207.7 vs. 159.9 minutes). There were 6 (9.0%) and 5 (9.6%) complications in ODG and LADG, respectively. During follow-up periods, tumor recurrence occurred in 7 (10.4%) patients of the ODG and in 4 (7.7%) patients of the LADG group. The 5-year survival rate of ODG and LADG was 88.6% and 91.3% (p=0.613), respectively. In view of lymph node involvement, 5-year survival rates were 96.0% in ODG versus 97.0% in LADG for patients with negative nodal metastasis (p=0.968) and 80.9% in ODG versus 78.7% in LADG for those with positive nodal metastasis (p=0.868).

CONCLUSION

Although prospective study is necessary to compare LADG with open gastrectomy for the treatment of advanced gastric cancer, laparoscopy-assisted distal gastrectomy might be considered as an alternative treatment for some pT2 gastric cancer.

Patient perception of natural orifice transluminal endoscopic surgery in an endoscopy screening program in Korea

PURPOSE

Natural orifice transluminal endoscopic surgery (NOTES) is a new method of accessing intracavitary organs in order to minimize pain by avoiding incisions in the body wall. The aim of this study is to determine patients' acceptance of NOTES in Korea and to compare their views about laparoscopic surgery and NOTES for benign and malignant diseases.

MATERIALS AND METHODS

The target number of total subjects was calculated to be 540. The subjects were classified into 18 sub-groups based on age groups, gender, and history of prior surgery. The questionnaire elicited information about demographic characteristics, medical check-ups, diseases, endoscopic and surgical histories, marital status and childbirth, the acceptance of NOTES, and the preferred routes for NOTES. In addition, the subjects chose laparoscopic surgery or NOTES for a hypothetical cholecystectomy and rectal cancer surgery, and responded to questions regarding the acceptable complication rate of NOTES, the appropriate cost of NOTES, and the reason(s) why they did not select NOTES.

RESULTS

486 of 540 patients (90.0%) who agreed to participate in this study completed the questionnaire. NOTES was preferred by the following patients: elderly; a history of treatment due to a disease; having regular check-ups; and a history of an endoscopic procedure (p<0.05). The most preferred route for NOTES was the stomach (67.1%). Eighty-four percent of the patients choosing NOTES responded that the complication rate of the new surgical method should be the same or lower than laparoscopic surgery. Vague anxiety over a new surgical method was the most common reason why NOTES was not selected in benign and malignant diseases (64% and 73%), respectively.

CONCLUSION

Patients appear to be interested in the potential benefits of NOTES and would embrace it if their concerns about safety are met. We believe that qualified surgical endoscopists can meet these safety concerns, and that NOTES development has the potential to flourish.

Comparative analysis of five-year survival results of laparoscopy-assisted gastrectomy versus open gastrectomy for advanced gastric cancer: a case-control study using a propensity score method

BACKGROUND

The aim of this study was to investigate the surgical and oncologic outcomes of laparoscopy-assisted gastrectomy (LAG) and open gastrectomy (OG) for advanced gastric cancer (AGC) using the case-control method with a sufficient follow-up period.

PATIENTS AND METHODS

The authors retrospectively analyzed 89 patients who underwent LAG and 345 patients who underwent OG for AGC between August 1999 and June 2007. A total of 176 matched cases were included in the final analysis.

RESULTS

Except for tumor size and reconstruction, there were no statistically significant differences in the clinicopathological parameters between the two groups. Although operation time was significantly longer for LAG than OG (228.3 vs. 183.6 min, p < 0.0001), first flatus time and postoperative hospital stay without complications were significantly shorter in the LAG group (3.2 vs. 3.7 days, p < 0.0001; 7.0 vs. 10.4 days, p < 0.0001, respectively). Operation-related complications occurred in 7 cases (8.0%) in both groups. 13 patients (14.8%) in the LAG group and 15 patients (17.1%) in the OG group had recurrence. There was no statistically significant difference in the 5-year and disease-free survival rates between LAG and OG.

CONCLUSIONS

LAG for AGC might be considered to be a minimally invasive surgery in some selected cases, although a well-designed prospective study comparing LAG with OG for AGC is needed.

A 5 year analysis of readmissions after radical subtotal gastrectomy for early gastric cancer

BACKGROUND

Many patients and surgeons have become interested in the quality of life after surgery for early gastric cancer. However, no reports on readmission rates for gastrectomy patients have been published, even if readmission greatly affects the patient's quality of life.

METHODS

In 530 consecutive early gastric cancer patients who underwent radical subtotal gastrectomy, we determined the incidence, cause, timing, type of treatment, and risk factors for readmission after discharge, and compared the readmission and nonreadmission groups with respect to clinicopathologic features and postoperative outcomes.

RESULTS

Overall, the 5 year and 1 month readmission rates after radical subtotal gastrectomy for early gastric cancer were 13.0% (69 of 530) and 7.5% (40 of 530), respectively. The most common cause for readmission was delayed gastric emptying (17 cases). Among a total of 82 readmissions, 34 patients (41.5%) were readmitted within 2 weeks of surgery. The type of treatment for 82 readmissions included 55 conservative therapies, 15 radiologic or endoscopic interventions, and 12 repeat laparotomies. No significant differences were detected in the clinicopathologic feature and postoperative outcomes between the two groups. The initial hospital stay remained significantly associated with readmission based on multivariate analysis.

CONCLUSIONS

Readmission rate at 1 month after radical subtotal gastrectomy is lower than that after major bowel surgery. Unusual postoperative recovery in a patient with vague symptoms should be managed with greater care before discharge. After subtotal gastrectomy for early gastric cancer, prevention of readmission can improve the patient's quality of life.

Coronary artery disease in a large renal transplant population: implications for management

Coronary artery disease (CAD) accounts for approximately one-half of the sizable mortality in patients with end-stage renal disease who have undergone transplantation. The study was a retrospective review of 1460 patients who underwent renal transplantation at the Mount Sinai Medical Center from January 1, 2000 to October 31, 2009. Noninvasive stress testing was performed in 848 patients (88.1%) with 278 patients (32.8%) having abnormal results. Cardiac catheterization was performed in 357 patients (37.1%) and of these, 212 patients had obstructive disease (59.4%). At 5 years posttransplant, there was no statistically significant difference between those with nonobstructive CAD and those who required percutaneous or surgical interventions (adjusted hazard ratio [aHR], 1.243; CI 95%, 0.513-3.010; p = 0.630). Those with medically managed obstructive CAD had significantly higher rates of death at the 5-year period when compared to those who received percutaneous intervention (aHR, 3.792; CI 95%, 1.320-10.895; p = 0.013) or those who received coronary artery bypass grafting (aHR, 6.691; CI 95%, 1.200-37.323). Because noninvasive imaging is poorly predictive of coronary disease in this high-risk population, an anatomic diagnosis is recommended. Revascularization may result in improved long-term outcomes.

Comparative study of complete and partial omentectomy in radical subtotal gastrectomy for early gastric cancer

PURPOSE

Curative surgery for patients with advanced or even early gastric cancer can be defined as resection of the stomach and dissection of the first and second level lymph nodes, including the greater omentum. The aim of this study was to evaluate the short- and long- term outcomes of partial omentectomy (PO) as compared with complete omentectomy (CO).

MATERIALS AND METHODS

Seventeen consecutive open distal gastrectomies with POs were initially performed between February and July in 2006. The patients' clinicopathologic data and post-operative outcomes were retrospectively compared with 20 patients who underwent open distal gastrectomies with COs for early gastric cancer in 2005.

RESULTS

The operation time in PO group was significantly shorter than that in CO group (142.4 minutes vs. 165.0 minutes, p=0.018). The serum albumin concentration on the first post-operative day in PO group was significantly higher than CO group (3.8 g/dL vs. 3.5 g/dL, p=0.018). Three postoperative minor complications were successfully managed with conservative treatment. Median follow-up period between PO and CO was 38.1 and 37.7 months. All patients were alive without recurrence until December 30, 2009.

CONCLUSION

PO during open radical distal gastrectomy can be considered a more useful procedure than CO for treating early gastric cancer. To document the long-term technical and oncologic safety of this procedure, a large-scale prospective randomized trial will be needed.

Predictive value of in vitro adenosine triphosphate-based chemotherapy response assay in advanced gastric cancer patients who received oral 5-Fluorouracil after curative resection

Purpose

To assess the usefulness of adenosine triphosphate-based chemotherapy response assay (ATP-CRA) results in advanced gastric cancer patients receiving adjuvant chemotherapy.

Materials and Methods

Sixty-two patients underwent curative surgical resection between January, 2006 and December, 2008. Their highly purified surgical specimens were evaluated by ATP-CRAs. Of the 62, 49 had successful assay results and they received either oral 5-fluorouracil or other chemotherapies. We retrospectively analyzed data for 24 patients who were treated with oral 5-fluorouracil and whose assays were successful.

Results

The median observation time was 24.6 months (range, 10.1 to 40.9 months). The median treatment time was 11.2 months (range, 1.2 to 17.7 months). The median age was 66 years (range, 30 to 81 years). Patients were grouped into sensitive- and resistant-groups according to adenosine triphosphate-based chemotherapy response results for fluorouracil. The sensitive-group showed a significantly longer time to relapse (not reached in the sensitive-group vs. 24.8 months in the resistant-group, p=0.043) and longer overall survival compared to the resistant-group (not reached in the sensitive-group vs. 35.7 months in the resistant-group, p=0.16, statistically insignificant).

Conclusion

Patients who receive curative surgical resection significantly benefit from sensitive adjuvant chemotherapy according to ATP-CRA results for time to relapse.

A prospective, randomized trial of esophageal submucosal tunnel closure with a stent versus no closure to secure a transesophageal natural orifice transluminal endoscopic surgery access site

BACKGROUND

Secure esophagotomy closure methods are a critical element in the advancement of transesophageal natural orifice transluminal endoscopic surgery (NOTES) procedures.

OBJECTIVE

To compare the clinical outcomes in swine receiving an esophageal stent or no stent after a submucosal tunnel NOTES access procedure.

DESIGN

Prospective, randomized, controlled trial in 10 Yorkshire swine.

SETTING

Academic center.

INTERVENTION

An endoscopic mucosectomy device was used to create an esophageal mucosal defect. An endoscope was advanced through a submucosal tunnel into the mediastinum and thorax, and diagnostic mediastinoscopy and thoracoscopy were performed. Ten animals were randomized to no stenting (n = 5) or stenting (n = 5) with a prototype small-intestine submucosa-covered stent.

MAIN OUTCOME MEASUREMENTS

Gross and histologic appearance of the mucosectomy and esophagotomy sites as well as clinical outcomes.

RESULTS

There was a significant difference in the overall procedure time between the animals that received a stent (35.0 min, range 27-46.0 min) and those with no closure (19.0 min, range 17-32 min) (P value = .018). The unstented group achieved endoscopic and histologic evidence of complete re-epithelialization and healing (100%) at the mucosectomy site compared with the stented group (20%, P = .048). Stent migration into the stomach occurred in two swine. Both groups had complete closure of the submucosal tunnel and well-healed esophagotomy sites.

LIMITATIONS

Animal study, small number of subjects.

CONCLUSION

The placement of a covered esophageal stent significantly interferes with mucosectomy site healing.