Recommendations for eligibility criteria concerning bariatric and metabolic surgical and endoscopic procedures for obese Hong Kong adults 2024: Hong Kong Society for Metabolic and Bariatric Surgery Position Statement.

The surgical management of obesity in Hong Kong has rapidly evolved over the past 20 years. Despite increasing public awareness and demand concerning bariatric and metabolic surgery, service models generally are not standardised across bariatric practitioners. Therefore, a working group was commissioned by the Hong Kong Society for Metabolic and Bariatric Surgery to review relevant literature and provide recommendations concerning eligibility criteria for bariatric and metabolic interventions within the local population in Hong Kong. The current position statement aims to provide updated guidance regarding the indications and contraindications for bariatric surgery, metabolic surgery, and bariatric endoscopic procedures.

Bariatric surgery is expensive but improves co-morbidity: 5-year assessment of patients with obesity and type 2 diabetes.

BACKGROUND: Bariatric surgery can be effective in weight reduction and diabetes remission in some patients, but is expensive. The costs of bariatric surgery in patients with obesity and type 2 diabetes mellitus (T2DM) were explored here. METHODS: Population-based retrospectively gathered data on patients with obesity and T2DM from the Hong Kong Hospital Authority (2006-2017) were evaluated. Direct medical costs from baseline up to 60 months were calculated based on the frequency of healthcare service utilization and dispensing of diabetes medication. Charlson Co-morbidity Index (CCI) scores and co-morbidity rates were measured to compare changes in co-morbidities between surgically treated and control groups over 5 years. One-to-five propensity score matching was applied. RESULTS: Overall, 401 eligible surgical patients were matched with 1894 non-surgical patients. Direct medical costs were much higher for surgical than non-surgical patients in the index year (€36 752 and €5788 respectively; P < 0·001) mainly owing to the bariatric procedure. The 5-year cumulative costs incurred by surgical patients were also higher (€54 135 versus €28 603; P < 0·001). Although patients who had bariatric surgery had more visits to outpatient and allied health professionals than those who did not across the 5-year period, surgical patients had shorter length of stay in hospitals than non-surgical patients in year 2-5. Surgical patients had significantly better CCI scores than controls after the baseline measurement (mean 3·82 versus 4·38 at 5 years; P = 0·016). Costs of glucose-lowering medications were similar between two groups, except that surgical patients had significantly lower costs of glucose-lowering medications in year 2 (€973 versus €1395; P = 0.012). CONCLUSION: Bariatric surgery in obese patients with T2DM is expensive, but leads to an improved co-morbidity profile, and reduced length of hospitalization.

REC8 functions as a tumor suppressor and is epigenetically downregulated in gastric cancer, especially in EBV-positive subtype.

REC8 meiotic recombination protein (REC8) was found to be preferentially methylated in gastric cancer (GC) using promoter methylation array. We aimed to elucidate the epigenetic alteration and biological function of REC8 in GC. REC8 was downregulated in 100% (3/3) of Epstein-Barr virus (EBV)-positive and 80% (8/10) of EBV-negative GC cell lines by promoter methylation, but the expression could be restored through demethylation treatment. Protein expression of REC8 was significantly lower in human primary gastric tumors than in adjacent non-tumor tissues. A negative correlation between methylation and mRNA expression of REC8 was observed in 223 gastric samples of The Cancer Genome Atlas study (r=-0.7018, P<0.001). The methylation level (%) of the REC8 promoter was significantly higher in EBV-positive gastric tumors than in EBV-negative gastric tumors, as shown by bisulfite genomic sequencing (77.6 (69.3-80.5) vs 51.4 (39.5-62.3), median (interquartile range); P<0.001); methylation levels in both subtypes of tumors were significantly higher than in normal stomach tissues (14.8 (4.2-24.0)) (both P<0.001). Multivariate analysis revealed that REC8 methylation was an independent factor for poor survival in GC patients (hazard ratio=1.68, P<0.05). REC8 expression significantly suppressed cell viability, clonogenicity and cell cycle progression; it induced apoptosis and inhibited migration of AGS-EBV (EBV-positive) and BGC823 (EBV-negative) GC cells, and it suppressed tumorigenicity in nude mice. In contrast, knockdown of REC8 in gastric epithelial immortalized GES-1 cells significantly increased cell viability, clonogenicity and migration ability. The tumor-suppressive effect of REC8 is mediated at least in part by the downregulation of genes involved in cell growth (G6PD, SLC2A1, NOL3, MCM2, SNAI1 and SNAI2), and the upregulation of apoptosis/migration inhibitors (GADD45G and LDHA) and tumor suppressors (PinX1, IGFBP3 and ETS2). In conclusion, REC8 is a novel tumor suppressor that is commonly downregulated by promoter methylation in GC, especially in the EBV-associated subtype. Promoter methylation of REC8 is an independent risk factor for the shortened survival of GC patients.

Epigenetic silencing of GDF1 disrupts SMAD signaling to reinforce gastric cancer development.

Accumulating evidence reveals the effectiveness of epigenetic therapy in gastric cancer. However, the molecular mechanisms and targets underlying such therapeutic responses remain elusive. Herein, we report an aberrant yet therapeutically rectifiable epigenetic signaling in gastric carcinogenesis. Administration of DNA-demethylating drug 5-aza-2'-deoxycytidine (5-aza-dC) reduced gastric cancer incidence by ~74% (P < 0.05) in N-nitroso-N-methylurea-treated mice. Through genome-wide methylation scanning, novel promoter hypermethylation-silenced and drug-targeted genes were identified in the resected murine stomach tumors and tissues. We uncovered that growth/differentiation factor 1 (Gdf1), a member of the transforming growth factor-ß superfamily, was silenced by promoter hypermethylation in control tumor-bearing mice, but became reactivated in 5-aza-dC-treated mice (P < 0.05). In parallel, the downregulated SMAD2/3 phosphorylation in gastric cancer was revived by 5-aza-dC in vivo. Such hypermethylation-dependent silencing and 5-aza-dC-mediated reactivation of GDF1-SMAD2/3 activity was conserved in human gastric cancer cells (P < 0.05). Subsequent functional characterization further revealed the antiproliferative activity of GDF1, which was exerted through activation of SMAD2/3/4-mediated signaling, transcriptional controls on p15, p21 and c-Myc cell-cycle regulators and phosphorylation of retinoblastoma protein. Clinically, hypermethylation and loss of GDF1 was significantly associated with reduced phosphorylated-SMAD2/3 and poor survival in stomach cancer patients (P < 0.05). Taken together, we demonstrated a causal relationship between DNA methylation and a tumor-suppressive pathway in gastric cancer. Epigenetic silencing of GDF1 abrogates the growth-inhibitory SMAD signaling and renders proliferation advantage to gastric epithelial cells during carcinogenesis. This study lends support to epigenetic therapy for gastric cancer chemoprevention and identifies a potential biomarker for prognosis.

Effect of local injection of mesenchymal stem cells on healing of sutured gastric perforation in an experimental model.

BACKGROUND: Mesenchymal stem cells are proposed to facilitate repair of organ injuries. The aim of this study was to investigate whether local injection of mesenchymal stem cells could accelerate healing of sutured gastric perforations. METHODS: Sutured gastric perforations in rats were treated either with local injection of mesenchymal stem cells (injected MSC group) or by topically spraying with fibrin glue containing mesenchymal stem cells (sprayed MSC group). Controls were treated by local injection of saline or topical spray of fibrin glue without mesenchymal stem cells. Healing of sutured gastric perforations was assessed on days 3, 5 and 7. RESULTS: Local injection of mesenchymal stem cells significantly promoted the healing of gastric perforations, with the highest pneumatic bursting pressure (mean(s.e.m.) 112·3(30·2) mmHg on day 5 versus 71·2(17·4) mmHg in saline controls; P = 0·001), minimal wound adhesions, and lowest incidence of wound dehiscence (3, 6, 5 and 1 animal on day 5 in control, fibrin, sprayed MSC and injected MSC groups respectively; n = 10 per group) and abdominal abscess (2, 2, 1 and no animals respectively on day 5). Histological examination showed that gastric perforations in the injected MSC group displayed reduced inflammation, and increased granulation and re-epithelialization. Sutured gastric perforations in the injected MSC group showed decreased expression of interleukin 6, and increased expression of transforming growth factor ß1 and epithelial proliferating cell nuclear antigen, compared with the other groups. CONCLUSION: Local injection of mesenchymal stem cells was more effective than topical application, and enhanced the healing of sutured gastric perforations by an anti-inflammatory process, enhanced cellular proliferation and earlier onset of granulation. Surgical relevance Abnormal healing of gastric perforation may cause morbidity and increase the risk of death. Adipose tissue-derived mesenchymal stem cells have been found to promote the healing of organ injuries through cellular differentiation and secretion of cytokines that stimulate cellular proliferation and angiogenesis, and suppress inflammation. This study explored the therapeutic potential of such mesenchymal stem cells for promotion of the healing of sutured gastric perforations. Mesenchymal stem cells delivered by local injection significantly enhanced the healing of gastric perforations with reduced severity of wound adhesion, and a decreased incidence of wound dehiscence and abdominal abscess. The increased expression of transforming growth factor ß1, proliferating cell nuclear antigen and reduced level of interleukin 6 provide evidence for enhancement of the healing process. Engrafted mesenchymal stem cells expressed α-smooth muscle actin as a marker of myofibroblasts. This preclinical study indicates that local injection of allogeneic adipose tissue-derived mesenchymal stem cells may have a potential therapeutic role in enhancing the healing of peptic ulcer disease and prevention of ulcer-related complications.

Laparoscopic Heller's cardiomyotomy achieved lesser recurrent dysphagia with better quality of life when compared with endoscopic balloon dilatation for treatment of achalasia.

Achalasia is a rare primary motility disorder of esophagus; treatments include endoscopic balloon dilatation (EBD) and laparoscopic Heller's cardiomyotomy (LC). This study compared EBD versus LC for treatment of achalasia with focus on quality of life (QoL) and prevalence of post-treatment gastroesophageal reflux disease. This was a retrospective cohort study of all patients diagnosed with achalasia older than 16 treated with either EBD or LC from January 1998 to April 2008. Patients' demographic data, comorbidities, postintervention GERD symptoms, QoL, recurrence of dysphagia, reintervention rate, hospital stay, and time to resumption of diet were collected. Sixty-eight patients were recruited into the study (EBD n= 50; LC n= 18). A significant improvement in QoL was found in patients undergoing LC (0.917 vs. 0.807, P= 0.006). A higher proportion of patients treated with EBD developed post-treatment gastroesophageal reflux symptoms (60.5% vs. 43.8%) when compared with LC, although statistically insignificant (P= 0.34). Patients treated with balloon dilatation had a greater percentage of recurrence of dysphagia (55.1% vs. 26.7%; P= 0.235) and need of reintervention (42.1% vs. 9.1%; P= 0.045). However, these patients had a shorter median hospital stay (1d [range 0-4]) and earlier resumption of diet (0d [range 0-3]). Although EBD is associated with a quicker perioperative recovery, LC accomplished a better QoL, lower incidence of recurrence of dysphagia, and need of reintervention after treatment for achalasia.

Long-term survival outcomes after definitive chemoradiation versus surgery in patients with resectable squamous carcinoma of the esophagus: results from a randomized controlled trial.

BACKGROUND: The aim of this study was to report on the 5-year survival outcomes of patients with resectable esophageal carcinoma who were treated by definitive chemoradiotherapy (CRT) or standard esophagectomy. PATIENTS AND METHODS: Between July 2000 and December 2004, 81 patients with resectable squamous cell carcinoma of the mid- or lower thoracic esophagus were randomized to receive esophagectomy or definitive CRT. The primary outcome was the overall survival and secondary outcomes included disease-free survival, morbidities and mortalities. RESULTS: Forty-five patients received esophagectomy and 36 patients were treated by definitive CRT. The overall 5-year survival favors CRT but the difference did not reach statistical significance (surgery 29.4% and CRT 50%, P=0.147). A trend to improved 5-year survival was observed for patients suffering from node-positive disease (P=0.061). The 5-year disease-free survival also showed a trend to significance favoring CRT (P=0.068), particularly for patients suffering from node-positive disease (P=0.017). Both the stage of the disease and albumin level were significant predictors to mortality and disease-free survival. CONCLUSIONS: Definitive CRT for squamous esophageal carcinoma resulted in comparable long-term survival to surgery. Further large-scale studies would be required to further investigate the role of CRT in node-positive patients. Clinicaltrials.gov identifier: NCT01032967.

Use of laparoscopic sleeve gastrectomy and adjustable gastric banding for suboptimally controlled diabetes in Hong Kong.

Bariatric surgery has recently been considered as an option for treatment of type 2 diabetes mellitus (T2DM). We assessed the effect of laparoscopic gastric banding and laparoscopic sleeve gastrectomy in a cohort of 39 T2DM Chinese patients with body mass index (BMI) over 30 kg/m(2) . Their mean body weights and BMI before surgery were 108 kg and 40 kg/m(2) , respectively, and 18 patients (46%) had suboptimal diabetic control (HbA1c >7%). After a mean follow-up of 27 months, 4 of 11 insulin-dependent patients (36%) were able to stop their insulin therapy, and 18 patients (46%) achieved remission of T2DM (HbA1c <6.5% without the use of medication). Glycaemic control remained poor in only nine other patients (27%). Logistic regression analysis showed that a short history of T2DM and high BMI could predict remission of diabetes after restrictive procedures. Our results suggest that restrictive surgery can significantly improve glycaemic control in obese T2DM patients.

Precut sphincterotomy using insulated angulotome.

A newly designed insulated angulotome was evaluated in a series of patients in whom biliary cannulation using conventional methods had failed and who required precut sphincterotomy. The new device consists of an insulated glass tip to prevent excessive electrocautery flow, and angulation to facilitate elevation of the papillary roof on cutting. A prospective series of patients with cholangitis or obstructive jaundice with failed biliary cannulation were recruited. The success of cannulation and complications following endoscopic retrograde cholangiopancreatography were analyzed. A total of 13 patients underwent precut sphincterotomy using the insulated angulotome. The immediate success of gaining biliary access after failed cannulation was 100 %. The mean size of the common bile duct on ultrasonography was 8.1 mm. The mean time to achieve biliary cannulation was 9 minutes 4 seconds, and there was no perforation or bleeding. This case series showed that precut sphincterotomy with the insulated angulotome can be safely performed without major complications.

Endoscopic submucosal dissection used for treating early neoplasia of the foregut using a combination of knives.

BACKGROUND: Endoscopic submucosal dissection (ESD) has emerged as a novel technique for achieving en bloc resection for early esophageal or gastric carcinoma limited to the mucosa. The authors report their experience with a combination of various devices to treat early neoplasia of the foregut using the ESD technique. METHODS: In this prospective case series, ESD was performed for early esophageal or gastric carcinoma limited to the mucosa. These lesions were staged by endoscopic ultrasonography before resection. Magnifying endoscopy and chromoendoscopy were used to locate the tumor and define the margin. The resection was accomplished with submucosal dissection using the insulated tip knife, the hook knife, and the triangular tip knife. The resected specimen was examined systematically for the lateral and deep margins. RESULTS: From January 2004 to March 2006, ESD was performed to manage 30 cases of early gastric or esophageal carcinoma. For 29 of these patients, R0 resection was successfully achieved. The mean operating time was 84.6 min. One patient experienced reactionary hemorrhage 12 h after resection, which was controlled endoscopically. There was no perforation. Most of the circumferential mucosal incisions were performed using the insulated tip knife (76.6%), whereas submucosal dissection was accomplished with a combination of various knives. One of the specimens showed involvement of the lateral margin, whereas another patient had two areas of new early gastric cancer 6 months after the initial procedure. These patients received salvage laparoscopically assisted gastrectomy. CONCLUSIONS: Endoscopic submucosal dissection to manage early neoplasia of the foregut can be achieved safely and effectively with a combination of knives.

Adjuvant chemoradiation for gastric cancer: experience in the Chinese population.

AIMS: The role of adjuvant chemoradiation for gastric cancer after curative R0 gastrectomy was first established by the US Intergroup 0116 study. Although confirmatory studies are in progress, few data are available regarding its application to the Chinese population. We describe our radiotherapy technique and report the treatment results in Hong Kong. MATERIALS AND METHODS: This was a single centre retrospective study on 63 Chinese patients who underwent adjuvant chemoradiation for gastric adenocarcinoma between June 2000 and December 2004. The treatment protocol was based on that of the Intergroup study. Computed tomography planned anteroposterior opposing field arrangement and treatment under breath hold at deep inspiration position were adopted. RESULTS: In total, 63 patients, mean age 50 years, with gastric cancer stage IB to limited metastatic IV disease were analysed. The median follow-up time was 27.2 months. The relapse-free survival and overall survival at 3 years were 50 and 54%, respectively. The recurrence pattern was dominated by distant failure and only one patient developed isolated locoregional recurrence. Of the 10 patients who had positive microscopic surgical margins after surgery, seven had recurred and died. On multivariate analysis, margin status was the only significant prognosticator for survival. Thirty per cent of patients experienced grade 3 or above acute toxicity (24% haematological, 14% gastrointestinal) and one patient died of neutropenic sepsis. There was one case of grade 3 late toxicity. CONCLUSIONS: The outcome after adjuvant chemoradiation for gastric cancer seemed to be favourable, with manageable toxicities, in the Chinese population. Locoregional failure was uncommon. Patients with microscopic surgical margin involvement had a very high failure rate despite adjuvant chemoradiation.

Irofulven as first line therapy in recurrent or metastatic gastric cancer: a phase II multicenter study by the Cancer Therapeutics Research Group (CTRG).

BACKGROUND: The purpose of this study was to evaluate the tolerability and efficacy of irofulven, a DNA interacting acylfulvene analog, as first line therapy for patients with recurrent or metastatic gastric cancer. PATIENTS AND METHODS: Twenty-three patients with recurrent or metastatic gastric cancer received irofulven at a dose of 0.45 mg/kg administered intravenously over 30-min infusion (up to a maximum of 50 mg), on days 1 and 8, every 3 weeks. RESULTS: The median number of cycles delivered per patient was 2 (range 1-6). Two patients (9%) had >or= 1-week delay in administration of subsequent cycle of chemotherapy. For the day 8 chemotherapy, dose reductions were required in seven patients (30%); dose omitting occurred in five patients (22%). Grade 3/4 anemia and neutropenia occurred in 22 and 17% of patients, respectively. There was no grade 4 thrombocytopenia and no neutropenic fever was observed. Of the 20 evaluable patients, there were no responses observed, 3 patients had stable disease after 2 cycles of treatment which was not confirmed by a further assessment. Median overall survival was 6.05 months (95% CI 4.55-9.39). CONCLUSIONS: Irofulven was tolerated at the dose of 0.45 mg/kg on days 1 and 8, every 3 weeks but showed no evidence of antitumor activity in patients with advanced gastric cancer.

Predictors of peptic ulcer rebleeding after scheduled second endoscopy: clinical or endoscopic factors?

BACKGROUND AND STUDY AIMS: In a previous study we demonstrated the efficacy of second-look endoscopy with therapy within 16 - 24 hours after index endoscopy in reducing major recurrent peptic ulcer bleeding. In this study, we sought to identify factors that might predict further rebleeding after this scheduled second-look endoscopy. PATIENTS AND METHODS: We studied 249 patients (181 men, 68 women) with acute bleeding peptic ulcers who were treated at the United Christian Hospital, Hong Kong from 1999 to 2002 and who underwent a scheduled second endoscopy. Those patients who developed rebleeding after the second endoscopy were evaluated, and possible predictive factors for rebleeding were analyzed using a logistic regression model. RESULTS: Of the 249 patients who underwent scheduled second-look endoscopy, 17 patients (6.8 %) developed rebleeding: seven of these patients were treated by another endoscopic therapy; ten patients required surgery. The overall mortality rate was 3.1 %. A logistic regression analysis performed on the possible predictive factors for rebleeding found that the following factors were associated with a significant risk of further rebleeding after scheduled second endoscopy: American Society of Anesthesiologists (ASA) grade III or grade IV status (odds ratio 3.81, 95 % CI 1.27 - 11.44), ulcer size greater than 1.0 cm (odds ratio 4.69, 95 % CI 1.60 - 13.80), and a finding of persistent stigmata of recent hemorrhage at the scheduled second endoscopy (odds ratio 6.65, 95 % CI 2.11 - 20.98). CONCLUSIONS: Endoscopic factors, including large ulcer size and the persistence of endoscopic stigmata of recent hemorrhage are important predictors for recurrent bleeding after scheduled second endoscopy.