Yun-Shi Zhong

Submucosal tunneling endoscopic resection: a new technique for treating upper GI submucosal tumors originating from the muscularis propria layer (with videos)

U T t s u g e o i T ( a ( f Upper GI submucosal tumors (SMTs) 3 cm are generally considered benign tumors. However, some such umors, especially mesenchymal neoplasms (including GI tromal tumors originating from the muscularis propria MP]), do have malignant potential.2 If tissue diagnosis is ttempted, the most challenging aspect in the diagnosis of MTs by needle biopsy is the sampling error when taking iopsy specimens of GI stromal tumors, which may show nly focal areas of malignant change.2 Asymptomatic GI MTs 3 cm could be followed-up with periodic endoscopy nd/or EUS or resection.3 However, some patients become tressed when told that they require periodic follow-up. As a esult, they feel the urge to seek a safe and efficacious reatment during the follow-up time. Conventional endocopic resection of tumors originating from the MP layer used o be discouraged because of incomplete resections or risk of erforation during procedures. This left such patients with wo choices: surgical resection or endoscopic follow-up. Enoscopic submucosal dissection (ESD)2 and new, emerging endoscopic techniques such as endoscopic full-thickness resection4 are now options for these patients.

Preoperative Enteral Immunonutrition Improves Postoperative Outcome in Patients with Gastrointestinal Cancer

ObjectivesThe purpose of this study was to evaluate the effect of preoperative immunonutrition pharmaceutics (IMPACT) diet versus standard enteral nutrition (EN) on the nutritional status and immunity of patients with colorectal or gastrointestinal (GI) cancer and to evaluate whether it influences the incidence of postoperative complication.MethodsSixty patients with GI cancer were randomly divided into 2 groups, immunonutrition (IM) and control diet (CT), each of which was fed with IMPACT and conventional diet, respectively, for 7 days before surgical procedures. Variables of nutritional status and immunity, postoperative complications, infections, and the days of postoperative hospitalization were measured.ResultsThere were no significant differences in the immunological and nutritional variables between the 2 groups preoperatively. The incidence of postoperative complications was significantly lower and the days of postoperative hospitalization were significantly decreased in the IM group. Serum concentrations of both prealbumin (PALB) and transferrin (TRF) were lower in the IM than in the CT group on postoperative day 3 (P < 0.01). TRF continued to be significantly lower in the CT group than in the IM group between day 4 and day 7. However, PALB was significantly lower than before operation in the IM group on postoperative day 3 and TRF was significantly higher in the IM than the CT group on postoperative day 3 (P < 0.05). Both PALB and TRF were significantly higher in the IM than the CT group on postoperative day 7 (P < 0.05). Postoperative immunoglobulin G (IgG) level in the IM group was higher than that in the CT group (13.35 ± 2.06 g/l vs. 9.59 ± 2.23 g/l, P < 0.05). CD4/CD8 ratio was significantly higher in the IM group (2.10 ± 0.51 vs. 1.62 ± 0.52, P < 0.05).ConclusionsPreoperative enteral IM in patients with GI cancer improves nutritional status and immunity and decreases the incidence of postoperative complications and infections.

Submucosal tumors of the esophagogastric junction originating from the muscularis propria layer: a large study of endoscopic submucosal dissection (with video)

BACKGROUND Given the high morbidity and mortality rates for surgery and the diminishment of quality of life caused by operative resection of the gastric cardia, a minor invasive treatment without loss of curability is desirable for submucosal tumors (SMTs) of the esophagogastric junction (EGJ). Endoscopic submucosal dissection (ESD) has been used successfully for the removal of esophageal or gastric SMTs; however, the EGJ has been regarded as a difficult location for ESD because of its narrow lumen and sharp angle. OBJECTIVE To evaluate the clinical impact of ESD for SMTs of the EGJ arising from the muscularis propria layer. DESIGN Single-center, prospective study. SETTING Academic medical center. PATIENTS 143 patients with 143 SMTs of the EGJ originating from the muscularis propria layer. INTERVENTIONS ESD. MAIN OUTCOME MEASUREMENTS Complications, en bloc resection rate, local recurrence, and distant metastases. RESULTS The average maximum diameter of the lesions was 17.6 mm (range 5 - 50 mm). The en bloc resection rate was 94.4% (135/143). All en bloc resection lesions showed both lateral and deep tumor-free margins, including 20 GI stromal tumors. Perforations occurred in 6 patients (4.2%, 6/143), and metal clips were used to occlude the defect. Four pneumoperitoneum and 2 pneumothorax caused by perforations were resolved with nonsurgical treatment. Local recurrence and distant metastasis have not occurred during a 2-year follow-up. LIMITATIONS Single-center, short follow-up. CONCLUSIONS ESD appears to be a safe, feasible, and effective procedure for providing accurate histopathologic evaluations, as well as curative treatments for SMTs of the EGJ originating from the muscularis propria layer.

Endoscopic submucosal dissection for treatment of esophageal submucosal tumors originating from the muscularis propria layer.

BACKGROUND The technique of endoscopic submucosal dissection (ESD), which was developed for en bloc resection of large lesions in the stomach, has been widely accepted for the treatment of early gastric cancer. It is being used for muscularis propria tumors of the digestive tract and has produced positive therapeutic effects. OBJECTIVE To study the feasibility of ESD for the removal of esophageal muscularis propria tumors and to evaluate the efficacy and safety of ESD for this treatment. DESIGN Single-center, retrospective study. SETTING University hospital. PATIENTS Thirty esophageal muscularis propria tumors from 28 patients were treated with ESD between December 2008 and December 2010. We defined esophageal muscularis propria tumors as esophageal submucosal tumors originating from the muscularis propria layer. INTERVENTION ESD. MAIN OUTCOME MEASUREMENTS Tumor characteristics, complications, en bloc resection rate, and local recurrence rate were evaluated. RESULTS Among the 28 patients, 11 were women (39.3%). The median age was 49.32 years (range 22-62 years). Mean (± SD) tumor size was 1.25 ± 0.70 cm (range 0.5-3.0 cm). Except for 2 failed cases (one changed to surgery and the other changed to nylon ligation), 26 cases with 28 tumors (2 cases had 2 tumors) originating from the muscularis propria of the esophagus were successfully resected by ESD. The en bloc resection rate was 93.3% (28/30). The median ESD procedure time was 73.5 minutes (range 30-120 minutes). Perforation occurred in 2 cases during dissection of the lesion, which was closed with metal endoclips. Pneumothorax occurred after the treatment in both cases. Closed thoracic drainages were initiated, and the patients recovered quickly without surgery. Pathological examination confirmed 27 leiomyomas and 1 GI stromal tumor. The curative resection rate was 100% (28/28). There was no recurrence during a 3 to 27-month follow-up period. LIMITATIONS The limitation of the study was its retrospective design. CONCLUSION ESD offers the promise of localized treatment of esophageal muscularis propria tumors with relatively few complications and low mortality. It makes the resection of whole lesions possible and provides precise histologic information.

Early diagnosis and management of delayed bleeding in the submucosal tunnel after peroral endoscopic myotomy for achalasia (with video)

Peroral endoscopic myotomy (POEM) has recently been described as a scar-free and less-invasive surgical myotomy option for treating achalasia. This procedure incorporates concepts of natural orifice transluminal endoscopic surgery and achieves endoscopic myotomy by using a submucosal tunnel as the operating space. Initial published experience in humans is more than encouraging despite a relatively short follow-up. Common complications of POEM include mucosal injury, subcutaneous emphysema, mediastinal emphysema, pneumothorax, pneumoperitoneum, and pleural effusion. Postoperative delayed bleeding in the submucosal tunnel is a rare complication after POEM, and only 1 patient with delayed bleeding has been reported in the literature to date. Despite its low incidence, delayed bleeding can result in serious conditions, such as massive bleeding, hemorrhagic shock, and death. Thus, early

Endoscopic submucosal dissection for foregut neuroendocrine tumors： An initial study

AIM To evaluate the feasibility and efficacy of endoscopic submucosal dissection (ESD) for foregut neuroendocrine tumors (NETs). METHODS From April 2008 to December 2010, patients with confirmed histological diagnosis of foregut NETs were included. None had regional lymph node enlargement or distant metastases to the liver or lung on preoperative computerized tomography scanning or endoscopic ultrasonography (EUS). ESD was attempted under general anesthesia. After making several marking dots around the lesion, a mixture solution was injected into the submucosa. The mucosa was incised outside the marking dots. Dissection of the submucosal layer beneath the tumor was performed under direct vision to achieve complete en bloc resection of the specimen. Tumor features, clinicopathological characteristics, complete resection rate, and complications were evaluated. Foregut NETs were graded as G1, G2, or G3 on the basis of proliferative activity by mitotic count or Ki-67 index. All patients underwent regular follow-up to evaluate for any local recurrence or distant metastasis. RESULTS Those treated by ESD included 24 patients with 29 foregut NETs. The locations of the 29 lesions are as follows: esophagus (n = 1), cardia (n = 1), stomach (n = 23), and duodenal bulb (n = 4). All lesions were found incidentally during routine upper gastrointestinal endoscopy for other indications, and none had symptoms of carcinoid syndrome. Preoperative EUS showed that all tumors were confined to the submucosa. Among the 24 gastric lesions, 16 lesions in 11 patients were type I gastric NETs arising in chronic atrophic gastritis with hypergastrinemia, while the other 8 solitary lesions were type III because of absence of atrophic gastritis in these cases. All of the tumors were removed in an en bloc fashion. The average maximum diameter of the lesions was 9.4 mm (range: 2-30 mm), and the procedure time was 20.3 min (range: 10-45 min). According to the World Health Organization 2010 classification, histological evaluation determined that 26 lesions were NET-G1, 2 gastric lesions were NET-G2, and 1 esophageal lesion was neuroendocrine carcinoma (NEC). Complete resection was achieved in 28 lesions (28/29, 96.6%), and all of them were confined to the submucosa in histopathologic assessment with no lymphovascular invasion. The remaining patient with NEC underwent additional surgery because the resected specimens revealed angiolymphatic and muscularis invasion, as well as incomplete resection. Delayed bleeding occurred in 1 case 3 d after ESD, which was managed by endoscopic treatment. There were no procedure-related perforations. During a mean follow-up period of 24.4 mo (range: 12-48 mo), local recurrence occurred in only 1 patient 7 mo after initial ESD. This patient successfully underwent repeat ESD. Metastasis to lymph nodes or distal organs was not observed in any patient. No patients died during the study period. CONCLUSION ESD appears to be a safe, feasible, and effective procedure for providing accurate histopathological evaluations and curative treatment for eligible foregut NETs.

MicroRNA-31 contributes to colorectal cancer development by targeting factor inhibiting HIF-1α (FIH-1)

The molecular mechanisms underlying colorectal cancer (CRC) tumorigenesis remain incompletely understood, partially contributing to the mortality of CRC. Advances in identification of novel mechanisms are therefore in an urgent need to fill the gap of our knowledge in CRC development. Here, we performed both in vitro and in vivo experiments along with in silico analysis to identify a new regulatory circuit that stimulated CRC tumorigenesis. In this report, we, for the first time, analyzed the correlation of FIH-1 level with clinicopathological features of CRC. The finding that FIH-1 was not only significantly decreased in tumor tissue as compared with the adjacent normal tissue but also was significantly correlated with tumor T stage status, indicated the role of FIH-1 as a tumor suppressor in CRC development. Moreover, we found the expression of miR-31, a short non-coding RNA which played a critical role in CRC development, was negatively correlated with FIH-1 expression in CRC samples and cell lines. Together with the result from luciferase report assay, it was demonstrated that miR-31 could directly regulate FIH-1 expression in CRC. This miR-31/FIH-1 nexus was further shown to control cell proliferation, migration and invasion in vitro and to control tumor growth in vivo. Additionally, correlation of the miR-31 expression with clinicopathologic features in CRC samples was examined in support of the driving role of newly identified miR-31/FIH-1 nexus in CRC tumorigenesis. These findings highlight the critical role of miR-31/FIH-1 nexus in CRC and reveal the contribution of miR-31 to CRC development by targeting FIH-1.

Risk factors for postoperative stricture after endoscopic submucosal dissection for superficial esophageal carcinoma

BACKGROUND AND STUDY AIMS Endoscopic submucosal dissection (ESD) is accepted as an established treatment modality for superficial esophageal carcinoma (SEC). The aim of this study was to identify risk factors for postoperative stricture after ESD for SEC. PATIENTS AND METHODS This was a retrospective study at a single institution. A total of 362 patients with SEC treated by ESD at Zhongshan Hospital, Shanghai, were enrolled between January 2007 and February 2012. Demographic and clinical parameters, including patient-, lesion-, and procedure-related factors, were analyzed for postoperative stricture risk factors. RESULTS The postoperative stricture rate was 11.6 % (42/362). The mean and median time from ESD to stricture was 58.5 ± 12.3 days (range 21 - 90 days) and 28 days, respectively. Mild, median, and severe stricture were observed in 16.7 % (7/42), 38.1 % (16 /42), and 45.2 % (19/42) of patients, respectively. Multivariate analysis revealed that circumferential extension of > 3/4 (odds ratio [OR] 44.2, 95 % confidence interval [CI] 4.4 - 443.6) and the depth of invasion above m2 (OR 14.2, 95 %CI 2.7 - 74.2) were independent risk factors for stricture. The degree of stricture was also related to lesion circumferential extension (relational coefficient φ = 0.47; P < 0.05) and histological depth (relational coefficient φ = 0.647; P < 0.05). CONCLUSIONS Circumferential extension and histological depth were reliable risk factors for postoperative stricture.

An adaptive adjusting mechanism for agent distributed blackboard architecture

Abstract Distributed blackboard is one of the popular agent communication architectures. However, in current agent systems, the distributed blackboard architecture is kept fixed after its initial setting, which may influence the system performance when network topology or agent cooperation relations are changed during operation. To solve the problem, this paper presents a novel mechanism for adjusting agent communication architecture. Based on graph theory, this mechanism provides a way to adjust the distributed blackboard architecture. The adjustment made to the architecture kept its validity, and the adjusted architecture outperforms the initial one in new network topology or agents cooperation relations, which are proved by the Mobile Ambients Calculus analysis and the simulation experiments. Therefore, the adjusting mechanism presented here can achieve the adaptation of the agent communication architecture to the changes of the network topology and agent cooperation relations.

Autonomous trust construction in multi-agent systems: a graph theory methodology

Trust mechanism always has two popular architectures: centralized fashion and distributed fashion. However, those two architectures are not well suited for multi-agent system since they cannot achieve the trust management autonomy. To achieve the trust management autonomy, the paper presents an autonomous trust construction model based on graph theory methodology. The presented model adopts the graph to describe the trust information, and uses the graph combination and path searching to construct the trust relation. Every agent can implement trust management autonomously; agent system can construct the global trust concept by the combination of trust information among agents; an agent can achieve the trust relation with other agent by trust path searching or trust negotiation. The simulation experiment results prove that the autonomous trust construction based on graph theory methodology is effective.