Metabolic Surgery in Korea

Metabolic surgery (MS) is a surgery that focuses on improving obesity-related comorbidities. It is often referred to as "diabetic surgery" because of its focus on treating type 2 diabetes. MS is distinguished from bariatric surgery (BS), in which weight loss is the primary goal. However, from a broader perspective, all surgeries for obese patients with diabetes can be considered MS. In Korea, metabolic and bariatric surgery (MBS) has been covered by the national health insurance since 2019. Patients with a body mass index (BMI) ≥35 or those with a BMI ≥30 and obesity-related comorbidities were eligible for MBS. Simultaneously, MS for patients with BMI values between 27.5 and 30 was partly reimbursed. The two major metabolic surgeries are Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG). According to the registry of the Korean Society of Metabolic and Bariatric Surgery, 1,560 metabolic surgeries for obese patients with diabetes were performed between 2019 and 2021 in Korea, which was approximately 35.6% of all bariatric surgeries. SG was the most common, followed by RYGB and duodenal switch surgery. When dividing the patients with diabetes who underwent MBS into two groups, specifically those with BMI <35 and ≥35, we found that SG was performed most common procedure in both groups. However, there was a higher proportion of RYGB and duodenal switch operation in the former, indicating a difference in surgical methods between the two groups. MS is a promising tool for the management of poorly controlled diabetes. More data are needed to establish proper patient selection and choice of surgical type.

Clinical Outcomes of Resectional Roux-en-Y Gastric Bypass, Compared to Sleeve Gastrectomy for Severe Obesity

PURPOSE

Resectional Roux-en-Y gastric bypass (RRYGB) is considered an alternative bariatric surgery in countries with a high incidence of stomach cancer because there is no excluded stomach after RRYGB. This study aimed to evaluate the efficacy and safety of RRYGB.

MATERIALS AND METHODS

This study included patients who underwent RRYGB and sleeve gastrectomy (SG) between 2011 and 2021. Surgical complications and metabolic and nutritional profiles were compared between the patients preoperatively and at 1, 6, and 12 months after surgery.

RESULTS

Twenty and seventy-six patients underwent RRYGB and SG, respectively; 7 in the SG group were lost to follow-up within 1 year. Surgical complications and baseline characteristics were comparable between two groups, except for diabetes (90.0% vs. 44.7%, p < 0.001). The decrease of HbA1c levels and incidence of reflux esophagitis were lower in the RRYGB group compared to that of SG at 1-year postoperative (-3.0% vs. -1.8%, p = 0.014; 0% vs. 26.7%, p = 0.027). The percentage of total weight loss at 1- year postoperative and incidence of dumping syndrome were comparable between the two groups. The RRYGB group had significantly lower total cholesterol level (161.9 mg/dl vs. 196.4 mg/dl, p < 0.001), but higher incidence of vitamin B12 deficiency (30.0% vs. 3.6%, p = 0.003) at 1 year postoperative compared to those of the SG group.

CONCLUSIONS

The RRYGB group had better postoperative outcomes for diabetes and dyslipidemia without increasing surgical complications compared to that of the SG group. Thus, RRYGB can be considered a safe and effective alternative in areas where gastric cancer is prevalent.

Impacts of sleeve gastrectomy on gastroesophageal reflux disease in severely obese Korean patients

BACKGROUND

Laparoscopic sleeve gastrectomy (LSG) has established popularity as a bariatric and metabolic surgery. However, the incidence of gastroesophageal reflux disease (GERD) following LSG is controversial. This study aims to describe the prevalence of de novo GERD after LSG.

METHODS

A retrospective chart review was performed for 130 patients who underwent a routine endoscopic surveillance before and after LSG between January 2013 and October 2018. The diagnosis of GERD was determined by presence of symptoms, history of PPI treatment, and endoscopic findings. The esophagogastroduodenoscopy (EGD) was performed annually after LSG and/or when the patients complained of severe reflux symptoms.

RESULTS

The prevalence of GERD before surgery was 18.5%. At 1 year after LSG, GERD was present in 70 (53.8%) of the 130 patients. GERD consisted of 55 patients with newly developed GERD, and 15 with preexisting GERD. 9 (37.5%) out of pre-existing GERD patients were free of symptoms and abnormal finding at EGD following LSG. During the LSG, 66 (50.8%) patients with hiatal hernia underwent re-approximation of the diaphragmatic crura. There was no significant relationship between hiatal hernia repair and postoperative GERD (p = 0.39). Number of patients taking PPI medication before and after LSG were 34 (26.2%) and 49 (37.7%). Out of 56 (43.1%) patients with endoscopic lesions, LA grade A was 31 (23.9%), B = 15 (11.5%), C = 4 (3.1%), and D = 6 (4.6%).

CONCLUSION

In this study, 42.3% (n = 55) of total patients developed newly developed GERD, and 7.7% (n = 10) had LA grade C or D esophagitis.

Comparative analysis of cancer gene mutations using targeted sequencing in matched primary and recurrent gastric cancers after chemotherapy

BACKGROUND

Investigation of responsiveness-associated genes using longitudinal mutation analyses after standard treatments in recurrent gastric cancer (GC) is limited.

OBJECTIVE

To evaluate the somatic mutations associated with resistance to combined treatment involving fluorouracil (FU) or platinum (PL) in advanced GC.

METHODS

Samples from patients with advanced GC treated with FU or PL alone, or surgery plus FU/PL, were studied. GC patients who relapsed after standard chemotherapy (FU/PL) and with presence of tumor samples from initial diagnosis and recurrence were included. Targeted sequencing analysis of 143 cancer-related genes was performed using an Oncomine Comprehensive Cancer Panel.

RESULTS

Matched samples of primary and recurrent lesions were analyzed in sixteen patients with GC. When genes with recurrent mutations in two or more patients were used as specific findings, a total of 26 genes were found. TP53 was the most predominantly increased allele frequency (AF) in recurrent GCs after standard treatment. The mutational AF of ERBB2, PTEN, and BRCA2 also commonly increased, suggesting the role of these mutations in treatment resistance, whereas the mutational AF of VLH, NF1, and STK11 frequently decreased in recurrent tumors, suggesting the role of these mutations in increasing sensitivity to treatment. TCGA gastric cancer data (n = 436) were analyzed, and mutation sites detected in 16 GC patients in this study were in agreement with TCGA cohort with some exceptions. Overall survival according to gene expression associated with chemotherapy responsiveness exhibited compatible patterns with gain or loss-of-function mutations of each gene.

CONCLUSIONS

Mutations in TP53, ERBB2, PTEN, BRCA2, VHL, NF1, and STK11 are candidate somatic alterations related to chemoresistance in GC.

Enhanced Recovery after Surgery in Bariatric Surgery

The enhanced recovery after surgery (ERAS) program is now widely applied in bariatric surgeries and other surgical procedures. The ERAS program in bariatric surgery consists of various components similar to that in colorectal surgery or other procedures. The major concept of the ERAS protocol relies on a multidisciplinary and multimodal approach to resolve various problems after surgical treatment. The key principles of the ERAS program in bariatric surgery include patient education, opioid-sparing multimodal pain management, prophylaxis of postoperative nausea and vomiting, goal-directed fluid therapy, and minimizing insulin resistance and catabolism. Several guidelines and studies, including randomized clinical trials and systematic reviews, have advocated for the ERAS program in bariatric surgery, which has consistently shown advantages in shortening hospital stay without increasing morbidity. The systematic application of the ERAS program in bariatric patients results in less pain and early recovery and should be routinely recommended.

Prediction of Postoperative Mortality in Patients with Organ Failure After Gastric Cancer Surgery

Background

Scarce data are available on the characteristics of postoperative organ failure (POF) and mortality after gastrectomy. We aimed to describe the causes of organ failure and mortality related to gastrectomy for gastric cancer and to identify patients with POF who are at a risk of failure to rescue (FTR).

Methods

The study examined patients with POF or in-hospital mortality in Seoul National University Hospital between 2005 and 2014. We identified patients at a high risk of FTR by analyzing laboratory findings, complication data, intensive care unit records, and risk scoring including Acute Physiology and Chronic Health Evaluation (APACHE) IV, Sequential Organ Failure Assessment (SOFA) score, and Simplified Acute Physiology Score (SAPS) 3 at ICU admission.

Results

Among the 7304 patients who underwent gastrectomy, 80 (1.1%) were identified with Clavien–Dindo classification (CDC) grade ≥ IVa. The numbers of patients with CDC grade IVa, IVb, and V were 48 (0.66%), 11 (0.15%), and 21 (0.29%), respectively. Pulmonary failure (43.8%), surgical site complication (27.5%), and cardiac failure (13.8%) were the most common causes of POF and mortality. Cancer progression (100%) and cardiac events (45.5%) showed high FTR rates. In univariate analysis, acidosis, hypoalbuminemia, SOFA, APACHE IV, and SAPS 3 were identified as risk factors for FTR (P < 0.05). Finally, SAPS 3 was identified as an independent predictive factor for FTR.

Conclusions

Cancer progression and acute cardiac failure were the most lethal causes of FTR. SAPS 3 is an independent predictor of FTR among POF patients after gastrectomy.

Bariatric/Metabolic Surgery Induces Noticeable Changes of Microbiota and Their Secreting Extracellular Vesicle Composition in the Gut

INTRODUCTION

Microbial ecology is reported to be an important regulator of energy homeostasis and glucose metabolism. Microbes secrete extracellular vesicles (EVs) during their proliferation and death to communicate with other cells. To investigate the roles of gut microbiota in glucose metabolism, we analyzed serial changes of gut microbe and microbial EV composition before and after bariatric/metabolic surgery (BMS).

METHODS

Twenty-eight Wistar rats were fed on high-fat diet (HFD) to induce obesity and diabetes. Five of them compared with 5 rats fed on regular chow diet (RCD). Among the remaining 23 rats, Roux-en-Y gastric bypass (RYGB) (n = 10), sleeve gastrectomy (SG) (n = 10), or sham operation (n = 3) was randomly performed. Gut microbiota and EVs from fecal samples were analyzed by 16S rDNA amplicon sequencing.

RESULTS

The present study showed that microbial diversity was decreased in HFD-fed rats versus RCD-fed rats. In addition, BMS reversed glucose intolerance and microbial richness which were induced by HFD. In terms of microbiota and microbial EV composition, both RYGB and SG enhance the composition of phyla Proteobacteria, Verrucomicrobia, and their secreting EVs, but decrease phylum Firmicutes and its EVs. We tried to demonstrate specific genera showed a significant compositional difference in obesity/diabetes-induced rats compared with normal rats and then restored similarly toward normal rats' level after BMS. At the genus level, Lactococcus, Ruminococcus, Dorea in Firmicutes(p), Psychrobacter in Proteobacteria(p), and Akkermansia in Verrucomicrobia(p) fit these conditions after BMS.

CONCLUSION

We suggest that these genera are the candidates contributing to obesity and diabetes improvement mechanism after BMS.

Near-infrared image-guided laparoscopic omental flap for breast cancer

BACKGROUND

Near-infrared (NIR) imaging with indocyanine green (ICG)-enhanced fluorescence is widely used in laparoscopic surgery. This study aimed to evaluate this technique's feasibility and usefulness in intraoperatively assessing vascular perfusion in a laparoscopically harvested omental flap.

MATERIALS AND SURGICAL TECHNIQUES

From March 2015 to February 2016, we prospectively evaluated patients undergoing breast cancer surgery followed by immediate breast reconstruction using a laparoscopically harvested omental flap. After laparoscopic preparation of the pedicled graft, the perfusion area of the omental graft was evaluated by using intraoperative Doppler ultrasonography and NIR imaging with intravenous ICG injection. Graft viability was evaluated by using Doppler ultrasonography 2 days postoperatively; for cosmetic outcome, Breast Cancer Conservative Treatment Cosmetic Results software was used 1 month postoperatively.

DISCUSSION

The laparoscopic harvesting of an omental flap was successfully performed in eight patients without conversion to open surgery. The mean time to the initial detection of ICG-enhanced fluorescence uptake was 3.25 ± 1.16 minutes. On intraoperative Doppler ultrasonography, a pulseless area ≥10% was detected in five patients (62.5%). However, NIR imaging revealed no patients had an ischemic portion ≥10%. There were no ICG-related intraoperative or postoperative complications. All patients showed patent vessels on Doppler ultrasonography 2 days postoperatively. Cosmetic outcomes were mostly favorable 1 month postoperatively. The Breast Cancer Conservative Treatment Cosmetic Results evaluation 1 month postoperatively showed excellent, good, and fair results, with no poor scores. With regard to vascular perfusion, ICG-enhanced NIR imaging is a feasible and useful tool for harvesting a laparoscopic omental flap in breast cancer patients.

Natural History of Gastric Cancer: Observational Study of Gastric Cancer Patients Not Treated During Follow-Up

BACKGROUND

Understanding the natural progression of untreated gastric cancer is critical for determining the disease prognosis as well as treatment options and timing. The aim of this study is to analyze the natural history of gastric cancer.

PATIENTS AND METHODS

We included patients with gastric cancer who had not received any treatment and were staged using endoscopy/endoscopic ultrasonography and computed tomography on at least two follow-up visits during intervals of nontreatment. Tumor volumes were also measured in addition to the staging. Survival of each stage at diagnosis was also analyzed.

RESULTS

A total of 101 patients were included. The mean follow-up period was 35.1 ± 34.4 months. The gastric cancer doubling time was 11.8 months for T1 and 6.2 months for T4. The progression time from early gastric cancer to advanced gastric cancer was 34 months. It decreased as the stages advanced: from 34 months between tumor-nodes-metastasis stage I and II to 1.8 months between stage III and IV. No variable was identified as a risk factor for cancer progression. The 5-year survival rates of untreated patients were 46.2% in stage I and 0% in stage II, stage III, and stage IV.

CONCLUSIONS

The progression and doubling times of gastric cancer shorten as the stages advance. Objective data reported in this study can be a critical factor in determining treatment timing and screening interval.

Multicenter results of long-limb bypass reconstruction after gastrectomy in patients with gastric cancer and type II diabetes

BACKGROUND/OBJECTIVE

The number of gastric cancer and type II diabetes mellitus is increasing in Korea. Metabolic surgery could be extended to gastric cancer patients with type II diabetes, especially those who are expected to achieve long-term survival. This study aimed to investigate change of diabetic status in patients undergoing long-limb Roux-en-Y bypass reconstruction compared with conventional Billroth II after curative gastrectomy. In total, 130 patients from five university hospital centers underwent long-limb Roux-en Y reconstruction after radical distal gastrectomy.

METHODS

In the long-limb group, the length of biliopancreatic limbs was more than 80 cm, and the length of the Roux limb was more than 80 cm. The control group comprised 96 patients who underwent conventional Billroth II reconstruction after distal gastrectomy. Follow-up data at three, six, nine, and 12 months were compared between the two groups.

RESULTS

Fasting blood sugar (FBS) and hemoglobin (Hb) A1c levels decreased more significantly in the long-limb Roux-en-Y group (FBS: 28.8 mg/dL; HbA1c: 0.72%). However, decreases in body mass index, albumin, and hemoglobin did not differ significantly between the two groups. Diabetes control significantly improved in the long-limb group. In multivariate analysis, long-limb bypass reconstruction was the significant factor for glycemic outcomes.

CONCLUSION

Roux-en-Y bypass with increased length of limbs after gastrectomy shows a favorable glycemic control for gastric cancer patients with type II diabetes without nutritional deficit and anemia. To obtain future perspectives, large-scale prospective studies with long-term outcomes are needed.

Efficacy of Assessing Intraoperative Bowel Perfusion with Near-Infrared Camera in Laparoscopic Gastric Cancer Surgery

BACKGROUND

Anastomotic leakage is a severe complication after gastric cancer surgery. Inadequate blood supply is regarded as an important risk factor. The aim of the study was to evaluate the feasibility and usefulness of intraoperative assessment of anastomotic vascular perfusion in gastric cancer surgery using near-infrared (NIR) camera imaging with indocyanine green (ICG)-enhanced fluorescence technique.

MATERIALS AND METHODS

From March 2015 to 2016, 30 patients undergoing laparoscopic gastrectomy for gastric cancer were prospectively evaluated. After completing the anastomosis, 2.5-5.0 mg of ICG was injected via peripheral veins. All anastomoses and resection margins were investigated using NIR camera to assess anastomotic perfusion. The assessment was performed using the adopted perfusion score of fluorescence activity, which ranged from 1 to 5 (1 = no uptake, and 5 = iso-fluorescent to all other segments).

RESULTS

Twenty-six distal gastrectomy (20 gastroduodenostomies, 6 gastrojejunostomies), 3 total gastrectomies (TG), and 1 pylorus-preserving gastrectomy were performed. The gap of visualization was 4.1 ± 3.2 minutes (range, 2-15) after ICG injection. Twenty-three of 30 patients (76.7%) showed technically successful ICG visualization. Among gastroduodenostomies, the average scores for gastric and duodenal sides were 3.5 and 3.7. Among gastrojejunostomies, the average scores for gastric, jejunal, and duodenal stump sides were 3.5, 4.0, and 3.8 (jejunojejunostomy, 3.5). Among TG, the average scores for esophagojejunostomy, duodenal stump, and jejunojejunostomy were 3.7, 4.0, 4.0, and 4.7. One case of leakage occurred in this study. Other complications included fluid collection and stenosis in 1 patient each.

CONCLUSIONS

This study showed intraoperative ICG angiography using NIR camera is feasible and provides imaging of anastomotic blood flow. Further studies are needed for practice.

Assessment of the Completeness of Lymph Node Dissection Using Near-infrared Imaging with Indocyanine Green in Laparoscopic Gastrectomy for Gastric Cancer

Purpose

This study assessed the feasibility of near-infrared (NIR) imaging with indocyanine green (ICG) in investigating the completeness of laparoscopic lymph node (LN) dissection for gastric cancer.

Materials and Methods

Patients scheduled for laparoscopic gastrectomy for treating gastric cancer were enrolled in the study. After intraoperative submucosal ICG injection (0.05 mg/mL), LN dissection was performed under conventional laparoscopic light. After dissection, the LN stations of interest were examined under the NIR mode to locate any extra ICG-stained (E) tissues, which were excised and sent for pathologic confirmation. This technique was tested in 2 steps: infra-pyloric LN dissection (step 1) and review of all stations after proper radical node dissection (step 2).

Results

In step 1, 15 patients who underwent laparoscopic pylorus-preserving gastrectomy (LPPG) and 15 patients who underwent laparoscopic distal gastrectomy (LDG) were examined. Seven and 2 E-tissues were obtained during LPPG and LDG, respectively. From the retrieved E-tissues, 1 and 0 tissue obtained during LPPG and LDG, respectively, was confirmed as LN. In step 2, 20 patients were enrolled (13 D1+ dissection and 7 D2 dissection). Six E-tissues were retrieved from 5 patients, and 1 tissue was confirmed as LN in the pathologic review. Overall, 15 E-tissues were detected and removed, and 2 tissues were confirmed as LNs in the pathologic review. Both nodes were from LN station #6, with 1 case each in the LDG and LPPG groups.

Conclusions

NIR imaging may provide additional node detection during laparoscopic LN dissection for gastric cancer, especially in the infra-pyloric area.

The comprehensive complication index (CCI) is a more sensitive complication index than the conventional Clavien-Dindo classification in radical gastric cancer surgery

BACKGROUND

The comprehensive complication index (CCI) integrates all complications of the Clavien-Dindo classification (CDC) and offers a metric approach to measure morbidity. The aim of this study was to evaluate the CCI at a high-volume center for gastric cancer surgery and to compare the CCI to the conventional CDC.

METHODS

Clinical factors were collected from the prospective complication data of gastric cancer patients who underwent radical gastrectomy at Seoul National University Hospital from 2013 to 2014. CDC and CCI were calculated, and risk factors were investigated. Correlations and generalized linear models of hospital stay were compared between the CCI and CDC. The complication monitoring model with cumulative sum control-CCI (CUSUM-CCI) was displayed for individual surgeons, for comparisons between surgeons, and for the institution.

RESULTS

From 1660 patients, 583 complications in 424 patients (25.5%) were identified. The rate of CDC grade IIIa or greater was 9.7%, and the overall CCI was 5.8 ± 11.7. Age, gender, Charlson score, combined resection, open method, and total gastrectomy were associated with increased CCI (p < 0.05). The CCI demonstrated a stronger relationship with hospital stay (ρ = 0.721, p < 0.001) than did the CDC (ρ = 0.634, p < 0.001). For prolonged hospital stays (≥30 days), only the CCI showed a moderate correlation (ρ = 0.544, p = 0.024), although the CDC did not. The CUSUM-CCI model displayed dynamic time-event differences in individual and comparison monitoring models. In the institution monitoring model, a gradual decrease in the CCI was observed.

CONCLUSIONS

The CCI is more strongly correlated with postoperative hospital stay than is the conventional CDC. The CUSUM-CCI model can be used for the continuous monitoring of surgical quality.

Effect and Mechanisms of Diabetes Resolution According to the Range of Gastric Resection and the Length of Anastomosis in Animal Models: Implication for Gastric Cancer Surgery in Patients with Diabetes Mellitus

BACKGROUND

To examine the effect and mechanism of Roux-en-Y gastric bypass (RYGB) on the improvement of diabetes according to the length of anastomosis and the gastric pouch volume in an animal model.

METHODS

Glucose intolerance was induced with a high-fat diet for 3 months in Sprague-Dawley rats. The animals were subjected to conventional RYGB (cRYGB; 5% gastric pouch with 15-cm Roux limb, 40-cm biliopancreatic limb; n = 9), short-limb RYGB (sRYGB; 5%, 8, 4 cm; n = 9), fundus-sparing RYGB (fRYGB; 30%, 8, 4 cm; n = 9), or sham operation (n = 9). After 6 weeks, oral glucose tolerance tests (OGTTs) were performed, and gut hormones including insulin, total GLP-1, GIP, and ghrelin were analyzed.

RESULTS

The cRYGB group showed significantly decreased food intake, body weight, and random glucose (p < 0.05). sRYGB resulted in a similar change of body weight loss to that of cRYGB, but with no improvement of hyperglycemia. The fRYGB group showed similar changes of body weight and random glucose to those of the sham group. In cRYGB and sRYGB, the level of insulin steeply increased until 30 min during OGTT. GLP-1 was higher at 30 min in cRYGB than in other groups, without significance. The fRYGB group showed a slowly increasing pattern in OGTT and GLP-1, and the lowest peak point in insulin and GIP.

CONCLUSION

cRYGB with 95% gastric resection was needed to achieve not only weight loss but also diabetes improvement, which could be related to the increase in GLP-1.

Anthropometric Study of the Stomach

Purpose

The aim of this study was to establish an anthropometric reference of the stomach for gastric cancer surgery and a modeling formula to predict stomach length.

Materials and Methods

Data were retrieved for 851 patients who underwent total gastrectomy at the Seoul National University Hospital between 2008 and 2013. Clinicopathological data and measurements from a formalin-fixed specimen were reviewed. The lengths (cm) of the greater curvature (GC) and lesser curvature (LC) were measured. Anthropometric data of the stomach were compared according to age, body weight, height (cm), and body mass index. To predict stomach length, two multiple regression analyses were performed.

Results

The mean lengths of the GC and LC were 22.2±3.1 cm and 16.3±2.6 cm, respectively. The men’s GC length was significantly greater than the women’s (22.4±3.1 cm vs. 21.2±2.9 cm, P=0.003). Patients aged >70 years showed significantly longer LC than those aged <50 years (16.9±2.9 cm vs. 15.9±2.4 cm, P=0.002). Patients with body weights >70 kg showed significantly longer GC than those with body weights <55 kg (23.0±2.9 cm vs. 21.4±3.2cm, P<0.001). In the predicted models, 4.11% of the GC was accounted for by age and weight; and 4.94% of the LC, by age, sex, height, and weight.

Conclusions

Sex, age, height, and body weight were associated with the length of the LC, while sex and body weight were the only factors that were associated with the length of the GC. However, the prediction model was not sufficiently strong.

Postoperative Quality of Life after Total Gastrectomy Compared with Partial Gastrectomy: Longitudinal Evaluation by European Organization for Research and Treatment of Cancer-OG25 and STO22

PURPOSE

The European Organization for Research and Treatment of Cancer quality-of-life questionnaire-OG25 was developed to evaluate the quality of life in patients with stomach and esophageal cancer. The following are included in the OG25 but not in the STO22: odynophagia, choked when swallowing, weight loss, trouble eating with others, trouble swallowing saliva, trouble talking, and trouble with coughing. In this study, we evaluated the quality of life of gastrectomized patients using both, the OG25 and the STO22.

MATERIALS AND METHODS

A total of 138 patients with partial gastrectomy (PG) (distal gastrectomy=91; pylorus-preserving gastrectomy= 47) and 44 patients with total gastrectomy (TG) were prospectively evaluated. Body weight and scores from the OG25 and STO22 were evaluated preoperatively and at 3 weeks, 3 months, and 6 months after surgery.

RESULTS

Patients with TG had significant weight loss compared to patients with PG. At 3 months, TG was associated with worse scores for dysphagia, eating, odynophagia, trouble eating with others, trouble with taste, and weight loss on the OG25. TG was also associated with dysphagia, eating restrictions, and anxiety on the STO22. The OG25 helped differentiate between the groups with respect to weight loss, odynophagia, choked when swallowing, and trouble eating with others. The OG25 scores changed over time and were significantly different.

CONCLUSIONS

The OG25 is a more sensitive and useful scale than the STO22 for evaluating the quality of life of gastrectomized patients, especially those with total gastrectomy.

Short- and Long-Term Outcomes After Gastrectomy in Elderly Gastric Cancer Patients

BACKGROUND

The number of elderly patients undergoing gastric cancer surgery has recently increased. We therefore evaluated the short- and long-term outcomes of elderly patients after curative gastrectomy.

METHODS

Overall, 824 patients were included in this retrospective study, which comprised of a non-elderly group (60-64 years; n = 558), an early-elderly group (75-79 years; n = 198), and a late-elderly group (≥80 years; n = 68) who underwent curative gastrectomy for gastric cancer between 2005 and 2009. Postoperative complications, according to the Clavien-Dindo classification, and survival of both elderly groups were compared with the non-elderly group. Postoperative life expectancy of the late-elderly group was compared with the corresponding aged general population.

RESULTS

Overall and severe (grade III or higher) complications in the early-elderly group were comparable with the non-elderly group; however, those in the late-elderly group were significantly more common than in the non-elderly group (p = 0.013 and p = 0.043, respectively). Multivariable analysis revealed that age ≥80 years was an independent risk factor for severe complications (hazard ratio 3.02, 95 % confidence interval 1.12-8.17; p = 0.029), and the disease-specific survivals of both elderly groups were comparable with the non-elderly group in all TNM stages. Postoperative life expectancy of late-elderly patients eliminating death from recurrence was comparable with the corresponding aged general population eliminating death from gastric cancer.

CONCLUSIONS

Gastric cancer surgery in elderly patients aged ≥80 years achieves reasonable long-term survival despite the increased risk of severe complications.

Manual Ambidexterity Predicts Robotic Surgical Proficiency

BACKGROUND

The manual dexterity of a surgeon is known to be related with surgical proficiency. Recently, as an objective measurement of surgical skills, inanimate methods using several types of simulators have been introduced. Using these simulators, we aimed to investigate the impact of manual dexterity on laparoscopic and robotic surgical proficiency.

MATERIALS AND METHODS

Fellow surgeons, surgical residents, and medical students (n = 32) participated in this study. For the measurement of dexterity, the sums and differences of the right and left hand performance times for the Grooved Pegboard Test were used as an index of dexterity speed and ambidexterity, respectively. The performance times during three sessions of laparoscopic suturing using a D-box trainer and the performance scores during three sessions using two robotic suturing programs with different degrees of difficulty provided by the da Vinci® Skills Simulator™ (Intuitive Surgical Inc., Sunnyvale, CA) were analyzed according to the measured manual dexterity.

RESULTS

Manual dexterity was not a significant factor for performance time during laparoscopic suturing, which was more influenced by participants' surgical experiences. In robotic suturing, the performance score was impacted significantly by manual dexterity in terms of ambidexterity rather than dexterity speed. For an easy robotic suturing task, the gap of proficiency between the lower and higher ambidexterity groups was decreased successively with each of the three sessions. However, that gap in cases with a difficult task was maintained consistently throughout all three sessions.

CONCLUSIONS

The degree of ambidexterity was an initial predictor for proficiency with simulated robotic suture. However, this relation could be lessened through a few sessions of training, although for a more difficult task further repetitions would be needed.

Clinical Outcome of Modified Laparoscopy-Assisted Proximal Gastrectomy Compared to Conventional Proximal Gastrectomy or Total Gastrectomy for Upper-Third Early Gastric Cancer with Special References to Postoperative Reflux Esophagitis

Purpose

This study evaluated the functional and oncological outcomes of proximal gastrectomy (PG) in comparison with total gastrectomy (TG) for upper-third early gastric cancer (EGC).

Materials and Methods

The medical records of upper-third EGC patients who had undergone PG (n=192) or TG (n=157) were reviewed. The PG group was further subdivided into patients who had undergone conventional open PG (cPG; n=157) or modified laparoscopy-assisted PG (mLAPG; n=35). Patients who had undergone mLAPG had a longer portion of their intra-abdominal esophagus preserved than patients who had undergone cPG. Surgical morbidity, recurrence, long-term nutritional status, and the incidence of reflux esophagitis were compared between the groups.

Results

The rate of postoperative complications was significantly lower for PG than TG (16.7% vs. 31.2%), but the five-year overall survival rate was comparable between the two groups (99.3% vs. 96.3%). Postoperative levels of hemoglobin and albumin were significantly higher for patients who had undergone PG. However, the incidence of reflux esophagitis was higher for PG than for TG (37.4% vs. 3.7%; P<0.001). mLAPG was related to a lower incidence of reflux esophagitis after PG (P<0.001).

Conclusions

Compared to TG, PG showed an advantage in terms of postoperative morbidity and nutrition, and there was a comparable prognosis between the two procedures. Preserving the intra-abdominal esophagus may lower the incidence of reflux esophagitis associated with PG.

Unaided Stapling Technique for Pure Single-Incision Distal Gastrectomy in Early Gastric Cancer: Unaided Delta-Shaped Anastomosis and Uncut Roux-en-Y Anastomosis

Purpose

Intracorporeal anastomosis is the most difficult procedure during pure single-incision distal gastrectomy (SIDG) that affects its generalization. We introduced unaided delta-shaped anastomosis (uDelta), a novel anastomosis technique, for gastroduodenostomy after pure SIDG, and compared the results with those of previously reported Roux-en-Y anastomosis (RY).

Materials and Methods

Between March 2014 and March 2015, SIDG with D1+ lymph node dissection was performed for early gastric cancer through a 2.5-cm transumbilical incision without any additional port. uDelta was performed by the operator alone, without any intracorporeal assistance.

Results

uDelta was performed on 11 patents, and uncut RY was performed on 5-patients without open or multiport conversion. R0 resection was performed in all cases. No significant differences were observed in mean age and body mass index between patients who underwent uDelta or RY. Mean operation times were 214.5±36.2 minutes for uDelta and 240.8±65.9 minutes for RY, which was not significantly different. Reconstruction time for uDelta was shorter than that for RY, with marginal statistical significance (26.1±8.3 minutes vs. 38.0±9.1 minutes, P=0.05). There were no intraoperative transfusions, 30-day mortality, or anastomosis-related complications in either group. Average length of hospital stay was 8.2±1.9 days in the uDelta group and 7.2±0.8 days in the RY group (P=0.320).

Conclusions

After carefully considering indications, uDelta can be a feasible and can be a reproducible reconstruction method after SIDG in early gastric cancer.

Comparison of outcomes according to the operation for type A esophageal atresia

Purpose

The purpose was to evaluate outcomes according to different operative strategies of type A esophageal atresia (EA).

Methods

All patients who underwent surgery for type A EA between 1980 and 2011 were included. Patients were divided into 2 groups: E-E group included patients who received esophageal end-to-end anastomosis, whereas E-G group included patients who received esophago-gastric tube anastomosis.

Results

Twenty-two patients were included. The median gestational age was 37.5 weeks. The median birth weight was 2.5 kg. Twenty-one patients underwent gastrostomy as initial procedures, and one patient underwent primary esophageal end-to-end anastomosis. The median gap between both esophageal ends was six vertebral distance (VD). Seven patients underwent primary anastomosis of the esophagus, and 14 patients underwent gastric replacement. Three patients (13.6%) had anastomotic leakage and 10 patients (45.5%) had anastomotic stenosis. Most of the patients (90.9%) had gastroesophageal reflux, but only two patients required antireflux surgery. The median VD was significantly shorter in E-E group than in E-G group (3 VD vs. 6 VD). Stenosis was significantly more often in E-E group, but there was no significant difference in leakage and reflux symptoms.

Conclusion

The treatment for type A EA can include E-E anastomosis or E-G anastomosis, depending on the length of the end-to-end interval after performing gastrostomy. Appropriate tension and blood flow in the anastomosis site are essential for preventing postoperative stenosis and leakage, and esophageal replacement with gastric tube is believed to be feasible and safe in cases where excessive tension is present.

Limited variation of DNA fingerprints (IS6110 and IS1081) in Korean strains of Mycobacterium tuberculosis

OBJECTIVE

To establish the usefulness of DNA fingerprinting for the epidemiology of Mycobacterium tuberculosis isolated from Korean tuberculosis patients.

METHODS

Comparison of restriction fragment length polymorphism (RFLP) patterns produced by southern hybridization of PvuII-digested chromosomal DNA.

RESULTS

IS6110-associated banding patterns of 41 isolates varied considerably, containing 1-13 copies. The RFLP pattern of the epidemiologically related M. tuberculosis isolates was identical in 8 of 10 groups of close contact patients. No noticeable differences in RFLP were observed between drug-sensitive and drug-resistant isolates. IS1081-containing restriction fragment analysis of 52 isolates showed 6 different banding patterns, and the C type was found dominant in Korea. Identification of G type M. tuberculosis, which has a 8.0 kb IS1081-containing PvuII fragment, is unusual because it has been observed only in M. bovis BCG so far.

CONCLUSIONS

IS6110 was a very useful tool for tracing the transmission route of tuberculosis; IS1081 was also useful for subdividing M. tuberculosis into several groups.

A 23-kilodalton protein, distinct from BvgA, expressed by virulent Bordetella pertussis binds to the promoter region of vir-regulated toxin genes

Bordetella pertussis coordinately regulates expression of its virulence factors in response to changing environmental conditions. These factors include pertussis toxin, adenylate cyclase toxin, and the filamentous hemagglutinin (FHA). The vir (or bvg) locus has been shown genetically to be required for this coordinate regulation. We have attempted to study the biochemical basis for coordinate regulation. DNA promoter deletion studies from other laboratories have shown that two tandem 20-bp repeats -157 to -117 bp upstream from the pertussis toxin promoter are essential for transcription. A similar 20-bp tandem repeat was found at the same site in the upstream region of the adenylate cyclase toxin promoter but is not present in the FHA or vir promoter region. Gel retardation revealed protein from virulent strains (able to express the virulence genes) but not from avirulent strains (unable to express the virulence genes) bound to the promoter region of the pertussis toxin gene, and this binding could be abolished by competition with an excess of oligonucleotides corresponding to either tandem repeat. The protein was determined to be 23 kDa by Southwestern (DNA-protein) analysis and could bind to either 20-bp oligonucleotide from the pertussis toxin promoter and either 20-bp oligonucleotide from the adenylate cyclase toxin promoter. BvgA, a 23-kDa protein encoded in the vir locus, has been reported to bind to a 14-bp inverted repeat in the FHA promoter which is not present in the pertussis toxin or adenylate cyclase promoter. We could not demonstrate binding of BvgA to the pertussis toxin promoter region. These data suggest that we have identified a second 23-kDa protein, distinct from BvgA but regulated by the vir operon, that binds to DNA sequences required for transcription of some, but not all, vir-regulated genes.