Confocal Laser Endomicroscopic Findings of Refractory Erosive Reflux Disease versus Non-Erosive Reflux Disease with Anti-Reflux Mucosectomy: An in vivo and ex vivo Study

Background/Aims

To date, there is no standard tool to diagnose gastroesophageal reflux disease (GERD). Typically, GERD is a non-erosive reflux disease (NERD) that does not present endoscopic abnormalities. Confocal laser endomicroscopy (CLE) has been shown to be an effective tool to identify and diagnose GERD. We aimed to investigate the cellular and vascular changes in vivo and ex vivo through CLE in patients with GERD.

Methods

Patients with refractory GERD who underwent mucosectomy were recruited. The distal esophagus was observed in vivo using CLE. Mucosectomy tissue was stained with acriflavine and CLE image was obtained ex vivo. We compared cellular and vascular changes in CLE between erosive reflux disease (ERD), NERD, and a control group.

Results

Eleven patients who underwent anti-reflux mucosectomy and five control patients were enrolled in the study. Patients with ERD and NERD presented greater dilated intercellular space than patients in the control group on CLE image. The diameter, number, and cross-sectional area of the intra-papillary capillary loops (IPCLs) were significantly larger in the ERD group than in the NERD group. The irregular shape of the IPCLs were observed in both patients with ERD and NERD.

Conclusions

The irregular shape of the IPCLs were significantly correlated with a positive diagnosis of GERD. CLE may diagnose NERD with high sensitivity and accuracy.

Hybrid Peroral Endoscopic Myotomy for Achalasia with Prior Treatment Failure

Achalasia is a neurodegenerative motility disorder caused by enteric neuron damage in the lower esophageal sphincter. Peroral endoscopic myotomy (POEM) is a standard treatment method for achalasia. Previous treatment modalities may affect the outcome of POEM as they cause submucosal fibrosis. We report a new technique called “hybrid POEM” for the treatment of patients with achalasia who had been previously treated with pneumatic balloon dilatation. We performed two techniques of POEM simultaneously, the standard POEM for the upper part of the submucosal tunnel and open POEM for the stenotic part of the esophagogastric junction. We dissected the mucosa and submucosa, and performed myotomy simultaneously. We overcame submucosal fibrosis of the esophagogastric junction, which was caused by the previous hybrid POEM treatment. The risks of mucosal incision and technical challenge of submucosal tunneling for the fibrotic area may be reduced by hybrid POEM.

Comparison of peroral endoscopic myotomy between de-novo achalasia and achalasia with prior treatment

Peroral endoscopic myotomy has been recognized as an effective treatment for patients with achalasia. Prior treatment may affect the outcome of subsequent treatment. We aimed to compare the safety and efficacy of POEM in treatment-naive patients vs. those with prior treatment failure. We retrospectively analyzed the data of achalasia patients who underwent POEM from November 2011 to January 2018. A comparative analysis was performed between De-Novo (DN) and Prior Treatment Failure (PTF) cases. Technical and clinical success, adverse events, operative time for POEM, hospital stay were compared between the two groups Overall, 209 patients with achalasia underwent POEM during the studied period, including 113 patients (54%) in the DN group and 96 patients (45%) in the PTF group. The baseline characteristics of the DN and PTF groups were not significantly different except for duration of disease. The PTF group had longer disease duration than the DN group. (7.92 ± 9.28 vs 4.45 ± 5.67 years, respectively, p = 0.005). Both groups were technically successful. Operative time was longer in the PTF group than that in the de-novo group, but the difference was not significant. The occurrence rates of complications were similar in both groups. Changes in the Eckardt score were comparable in the DN and PTF cases. IRP and LES pressure decreased after POEM. After 6 months, more patients suffered from reflux symptoms in the PTF group, but DeMeester score and endoscopic evaluation were not significantly different POEM is safe and equally effective for patients with prior treatment failure as well as de-novo patients up to 6 months post treatment.

Dietary prevention of Helicobacter pylori-associated gastric cancer with kimchi

To prove whether dietary intervention can prevent Helicobacter pylori-induced atrophic gastritis and gastric cancer, we developed cancer preventive kimchi (cpKimchi) through special recipe and administered to chronic H. pylori-initiated, high salt diet-promoted, gastric tumorigenesis mice model. H. pylori-infected C57BL/6 mice were administered with cpKimchi mixed in drinking water up to 36 weeks. Gross and pathological gastric lesions were evaluated after 24 and 36 weeks, respectively and explored underlying molecular changes to explain efficacies. Cancer preventive actions of anti-inflammation and anti-mutagenesis were compared between standard recipe kimchi (sKimchi) and special recipe cpKimchi in in vitro H. pylori-infected cell model. The erythematous and nodular changes, mucosal ulcerative and erosive lesions in the stomach were noted at 24^th weeks, but cpKimchi administration significantly ameliorated. After 36^th weeks, scattered nodular masses, some ulcers, and thin nodular gastric mucosa were noted in H. pylori-infected mice, whereas these gross lesions were significantly attenuated in cpKimchi group. On molecular analysis, significant expressions of COX-2 and IL-6, activated NF-κB and STAT3, increased apoptosis, and marked oxidative stresses were noted in H. pylori-infected group relevant to tumorigenesis, but these were all significantly attenuated in cpKimchi group. cpKimchi extracts imparted significant selective induction of apoptosis only in cancer cells, led to inhibition of H. pylori-induced proliferation, while no cytotoxicity through significant HO-1 induction in non-transformed gastric cells. In conclusion, daily dietary intake of cpKimchi can be an effective way either to rejuvenate H. pylori-atrophic gastritis or to prevent tumorigenesis supported with the concerted actions of anti-oxidative, anti-inflammatory, and anti-mutagenic mechanisms.

Jackhammer esophagus treated by a peroral endoscopic myotomy

A 49-year-old woman visited our hospital with dysphagia and chest pain. In another hospital, she was diagnosed as reflux esophagitis. Although she had taken proton pump inhibitor and prokinetics drugs for a long time, she was not relieved of any symptoms. On the basis of high resolution manometry and endoscopic ultrasonography findings, Jackhammer esophagus was diagnosed. In this patient, peroral endoscopic myotomy (POEM) was performed for long myotomy of thickened circular muscle. During the procedure, there were no significant complications and she was discharged uneventfully. Symptoms were completely improved during three months after POEM. Here, we report on a case of Jackhammer esophagus treated by POEM.

Overview of gastrointestinal cancer prevention in Asia

"War on cancer" was declared through the National Cancer Act by President Richard Nixon in 1971, but cancer statistics from the American Cancer Society and other sources indicated the failure of this war, suggesting instead focus on the message that a "prevention strategy" might be much more effective than cancer treatment. While cancer statistics notoriously showed sharp increases in incidence as well as in mortality concurrent with economic growth in Asia, fortunately Asian countries benefit from plentiful resources of natural compounds, which can prevent cancer. Just like cancer chemotherapeutics targeted to kill cancer cells in Western countries, natural agents activating molecular mechanisms for cancer prevention, reversion of premalignant tumors, and even ablation of cancer stem cells, are very abundant in Asia. Currently, these natural agents are under very active investigations targeting the hallmarks of cancer prevention, including selective induction of apoptosis in cancer cells, suppression of growth factors or their signaling, suppression of cell proliferation and of cancer-promoting angiogenesis, induction of mesenchymal-epithelial transition, and disruption of the tumor microenvironment, developing promising cancer preventive agents. However, Asia is the most populous continent in the world and some Asian countries do not have the resources to implement cancer screening programs for early detection or treatment. In addition, despite the excellent cancer preventive screening strategies in some Asian countries, well-designed clinical trials for cancer prevention are somewhat delayed compared to Western countries. In this review article, several phytochemicals/phytoceuticals produced and studied in different Asian countries will be introduced, including Korean red ginseng (pride of Korea), curcumin (Indian spice for life), black or green tea (popular in Japan/Sri Lanka), genistein from tofu (famous Chinese food), diallylsulfide or S-allylcysteine (garlic, popularly consumed as a food ingredient in many Asian countries), capsaicin, 6-gingerol, flavopiridol, and silymarin (abundant in various Asian foods). Whereas in Western countries cancer chemotherapeutics involve strategies not only to block the growth of the primary tumor, but also to inhibit its progression to metastatic disease, the endless pursuit of effective agents for cancer prevention may be a unique and featured strategy in Asia. More active efforts for clinical application of these principles should be supported.

Cost comparison between surgical treatments and endoscopic submucosal dissection in patients with early gastric cancer in Korea

BACKGROUND/AIMS

This study was conducted to evaluate whether medical costs can be reduced using endoscopic submucosal dissection (ESD) instead of conventional surger-ies in patients with early gastric cancer (EGC).

METHODS

Pa-tients who underwent open gastrectomy (OG), laparoscopy-assisted gastrectomy (LAG), and ESD for EGC were recruited from three medical institutions in 2009. For macro-costing, the medical costs for each patient were derived from the ex-penses incurred during the patient's hospital stay and 1-year follow-up. The overall costs in micro-costing were determined by multiplying the unit cost with the resources used during the patients' hospitalization.

RESULTS

A total of 194 patients were included in this study. The hospital stay for ESD was 5 to 8 days and was significantly shorter than the 12-day hospital stay for OG or the 11- to 17-day stay for LAG. Using macro-costing, the average medical costs for ESD during the hospital stay ranged from 2.1 to 3.4 million Korean Won (KRW) per patient, and the medical costs for conventional surgeries were estimated to be between 5.1 million and 8.2 million KRW. There were no significant differences in the 1-year follow-up costs between ESD and conventional surger-ies.

CONCLUSIONS

ESD patients had lower medical costs than those patients who had conventional surgeries for EGC with conservative indications. (Gut Liver, 2015;9174-180).

Role of proton pump inhibitors in preventing hypergastrinemia-associated carcinogenesis and in antagonizing the trophic effect of gastrin

Gastrin is the main hormone stimulating gastric acid secretion, but it exerts proliferative and anti-apoptotic actions on various cancer cell types, in addition to its well-known trophic effect on enterochromaffin-like cells. As treatment with proton pump inhibitors (PPIs) increases the biosynthesis and secretion of gastrin, it has been postulated that treatment with PPIs could increase the risk of cancer, especially in Barrett's esophagus, gastric carcinoids, and colorectal cancer (CRC). Some tumors produce gastrin of their own, which can act in an autocrine manner to promote tumor growth. In addition, gastrin is known to foster the tumor microenvironment. However, in spite of these potentially increased cancer risks due to PPI-induced hypergastrinemia, prospective, large-scale cohort studies did not show an increase in CRC prevalence. The question as to why the long-term use of PPIs was not associated with an increased cancer risk of CRC might be answered by the fact that the PPIs antagonized the trophic effects of hypergastrinemia. Furthermore, the blockade of proton pumps or potassium channels in cancer cells could limit the abnormal glycolytic energy metabolism of cancer cells. Apart from their suppressive effect on gastric acids, PPIs exert an anti-tumor effect through the selective induction of apoptosis as well as an anti-inflammatory effect, and they protect cells from developing chemo- or radiotherapeutic resistance. Moreover, the anti-carcinogenic actions of PPIs were augmented with PPI-induced hypergastrinemia. Together with their potential targeted killing of cancer stem cells, these effects demonstrate their potential anti-cancer actions.

Randomized controlled trial of low-volume bowel preparation agents for colonic bowel preparation: 2-L polyethylene glycol with ascorbic acid versus sodium picosulfate with magnesium citrate

PURPOSE

Both 2-L polyethylene glycol with ascorbic acid (2-L PEG/Asc) and sodium picosulfate with magnesium citrate (SP/MC) are low-volume combined agents for colonic preparation. The aim of the current study was to compare the preparation adequacy and patient tolerability of 2-L PEG/Asc and SP/MC.

METHODS

We performed a prospective randomized controlled study in outpatients undergoing daytime colonoscopy at a tertiary academic hospital. We compared preparation adequacy based on the Boston Bowel Preparation Scale (BBPS), polyp and adenoma detection rate (PDR and ADR), compliance, tolerability for ease and palatability, intention to reuse, and patient satisfaction using a questionnaire between 2-L PEG/Asc and three sachets of SP/MC, both given in a split-dose method.

RESULTS

A total of 388 patients were evaluated based on intention to treat (ITT) and 356 patients per protocol (PP). No significant differences in preparation adequacy were observed in ITT and PP analyses, based on the BBPS (p > 0.05). The PDR and ADR were greater than 60 and 40% in both groups, respectively (p > 0.05). Compliance levels were higher in the 2-L PEG/Asc group than in the SP/MC group (p < 0.001). Satisfaction (ITT, p = 0.014; PP, p = 0.032) and palatability (ITT and PP, p < 0.001) levels were higher in the SP/MC group than in the 2-L PEG/Asc group, but values for tolerability for ease and intention to reuse were similar in both groups (ITT and PP, p > 0.05).

CONCLUSIONS

Both 2-L PEG/Asc and SP/MC had adequate bowel cleansing efficacy to satisfy PDR and ADR as quality indicator and had showed similar tolerability.

How to predict adequate bowel preparation before colonoscopy using conventional polyethylene glycol: prospective observational study based on survey

BACKGROUND AND AIM

The present study investigated the conditions and predictive factors for adequate bowel preparation using 4-L polyethylene glycol (PEG) preparation in clinical practice.

METHODS

We conducted a prospective-survey-based observational study. The survey consisted of 14 questions that assessed the preparation method (group 1: split method for morning colonoscopy; group 2: full-volume method for same-day afternoon colonoscopy; group 3: full-volume method for next-day morning colonoscopy), dinner type and timing the day before colonoscopy, elapsed time after PEG consumption, and stool character and defecation frequency immediately before colonoscopy. Preparation status was compared using the Boston bowel preparation scale (BBPS).

RESULTS

Total of 465 surveys (391 for group 1, 55 for group 2, 19 for group 3) were conducted. Mean BBPS score was highest in group 1 and lowest in group 3 (P < 0.001). Fasting dinner before colonoscopy group showed a higher mean BBPS than the diet group; eating before 6 p.m. and a low-residue diet showed a higher mean BBPS (P < 0.05). Defecation frequency (>5 times) was related to adequate preparation in the left colon and elapsed time (<5 h) to that in the right colon (P < 0.05). Liquid stool without solid material immediately before colonoscopy was related to adequate preparation (P < 0.001).

CONCLUSION

In bowel preparation with 4-L PEG, elapsed time after PEG consumption (<5 h), defecation frequency (>5 times) and liquid stool without solid material immediately before colonoscopy were predictive factors for adequate bowel preparation just before colonoscopy.

Long-term outcomes of balloon dilation versus botulinum toxin injection in patients with primary achalasia

BACKGROUND/AIMS

We compared the long-term outcomes of balloon dilation versus botulinum toxin injection in Korean patients with primary achalasia and identified factors predicting remission.

METHODS

We included 73 patients with achalasia newly diagnosed between January 1988 and January 2011. We ultimately enrolled 37 of 55 patients with primary achalasia through telephone interviews, who were observed for over 1 year. Short-term outcomes were evaluated from the medical records based on symptom relief after 1 month of treatment. Long-term outcomes were evaluated in a telephone interview using a questionnaire.

RESULTS

Twenty-five patients were administered a botulinum toxin injection and 12 underwent balloon dilation. One month after the botulinum toxin injection, improvements were seen in chest pain (14 [56.0%] to 4 patients [16.0%]), regurgitation (16 [64.0%] to 4 [16.0%]), and dysphagia (25 [100.0%] to 5 [20.0%]). In the balloon dilation group, chest pain (8 [66.7%] to 1 [8.3%]), regurgitation (11 [91.7%] to 1 [8.3%]), and dysphagia (12 [100.0%] to 1 [8.3%]) had improved. A significant difference was observed in the mean remission duration between the botulinum toxin injection and balloon dilation groups (13 months [range, 1 to 70] vs. 29 months [range, 6 to 72], respectively; p = 0.036). Independent factors predicting long-term remission included treatment type (odds ratio [OR], 6.982; p = 0.036) and the difference in the lower esophageal sphincter pressure (OR, 7.198; p = 0.012).

CONCLUSIONS

Balloon dilation may be more efficacious than botulinum toxin for providing long-term remission in Korean patients with achalasia. Follow-up manometry may predict the long-term outcome.

Ever-changing endoscopic treatment for early gastric cancer: Yesterday-today-tomorrow

Endoscopic resection has been an optimal treatment for selected patients with early gastric cancer (EGC) based on advances in endoscopic instruments and techniques. As endoscopic submucosal dissection (ESD) has been widely used for treatment of EGC along with expanding ESD indication, concerns have been asked to achieve curative resection for EGC while guaranteeing precise prediction of lymph node metastasis (LNM). Recently, new techniques including ESD or endoscopic full-thickness resection combined with sentinel node navigation enable minimal tumor resection and a laparoscopic lymphadenectomy in cases of EGC with high risk of LNM. This review covers the development and challenges of endoscopic treatment for EGC. Moreover, a new microscopic imaging and endoscopic techniques for precise endoscopic diagnosis and minimally invasive treatment of EGC are introduced.

The clinical features and treatment modality of esophageal neuroendocrine tumors: a multicenter study in Korea

BACKGROUND

Neuroendocrine tumors (NETs) of the esophagus are extremely rare, and few cases have been reported worldwide. Thus, a comprehensive nationwide study is needed to understand the characteristics of and treatment strategy for esophageal NETs.

METHODS

We collected data on esophageal NET patients from 25 hospitals in Korea from 2002-2012. The incidence, location, clinical symptoms, histopathology, treatment response, and the biochemical, radiologic and endoscopic characteristics of esophageal NETs were surveyed.

RESULTS

Among 2,037 NETs arising in different gastrointestinal sites, esophageal NETs were found in 26 cases (1.3%). The mean patient age was 60.12 ± 9.30 years with a 4:1 male predominance. In endoscopic findings, 76.9% (20/26) of NETs were located in the lower third of the esophagus and the mean size was 2.34 ± 1.63 cm. At diagnosis, more than half the patients (15/26, 57.7%) had regional lymph node metastasis or widespread metastasis. Endoscopic resection was conducted in three cases, and in all three of them, lymph node metastasis was not found and tumor size was below 1.0 cm. All tumors were completely removable through endoscopic procedures and there was no recurrence during the follow-up period. Eighteen other patients received an operation, chemotherapy or both. Among them, nine patients (50.0%) expired because of the progression of their cancer or post-operative complications. In Kaplan-Meier survival analysis, only tumor size (more than 2.0 cm) showed prognostic significance (P = 0.045).

CONCLUSIONS

Despite the general assumption that gastrointestinal NETs are benign and slow-growing tumors, the prognosis of advanced esophageal NETs is not favorable.

Impedance Analysis Using High-resolution Impedance Manometry Facilitates Assessment of Pharyngeal Residue in Patients With Oropharyngeal Dysphagia

Background/Aims

Impedance analysis using high-resolution impedance manometry (HRIM) enables the recognition of pharyngeal residue in patients with oropharyngeal dysphagia. The aims of this study were to evaluate appropriate criteria for impedance analysis in a large patient cohort, as well as the diagnostic accuracy and agreement of analysis performed by HRIM trainees.

Methods

We reviewed 33 controls (13 males; median age, 61.2 years) and 104 oropharyngeal dysphagia patients (61 males; median age, 70.4 years) who underwent a flexible endoscopic evaluation of swallowing study (FEES) and HRIM. Two experts compared the pharyngeal residue on FEES and impedance color pattern at 1,000, 1,500 and 2,000 Ω of the impedance bar. Three trainees were given a 60 minutes tutorial to determine the diagnostic accuracy and agreement of this analysis.

Results

The diagnostic sensitivity of experts for predicting liquid residue was 73.1% for 1,000 Ω, 96.2% for 1,500 Ω and 100% for 2,000 Ω. Significantly higher sensitivity was observed at 1,500 Ω compared to 1,000 Ω (P < 0.001). The diagnostic specificity of experts for liquid residue was 98.3% for 1,000 Ω, 96.6% for 1,500 Ω and 83.1% for 2,000 Ω. There was a higher specificity at 1,500 Ω compared to 2,000 Ω (P = 0.008). The κ value among the 3 trainees was 0.89 and the diagnostic accuracy of the trainees for liquid residue was comparable to that of the experts.

Conclusions

The impedance analysis at 1,500 Ω provides more accurate information for the detection of liquid residue, irrespective of the level of expertise.

High-resolution impedance manometry facilitates assessment of pharyngeal residue and oropharyngeal dysphagic mechanisms

The utility of high-resolution impedance manometry (HRIM) for evaluating oropharyngeal dysphagia (OPD) has been investigated. These approaches are limited because of the sophisticated methodology. A method of transforming HRIM into a simple and useful diagnostic tool for evaluating OPD is needed. A videofluoroscopic swallowing study (VFSS) and HRIM were performed by independent blinded examiners in 26 consecutive healthy volunteers (12 men; median age, 56.5 years) and 10 OPD patients (five men; median age, 59.5 years). Upper esophageal sphincter (UES) relaxation parameters were measured using a standard HRIM protocol. Peristalsis and bolus transit of the pharyngoesophageal (PE) segment were assessed using an HRIM-modified protocol in which the catheter was pulled back 10 cm. PE bolus transits were evaluated with an impedance contour pattern (linear vs. stasis) method. A significant difference was observed between the manometric measures of healthy volunteers and OPD patients for only the duration of pharyngeal contraction (0.49 ± 0.19 vs. 0.76 ± 0.33 s, P = 0.04). The percentage agreement and kappa value for detecting pharyngeal residue between the VFSS and the impedance analysis were 100% and 1.00, respectively. HRIM allowed for comprehensive assessment of abnormal pharyngeal components that caused pharyngeal residue on VFSS in two patients; reduced base of the tongue versus weak pharyngeal contraction in one, and reduced relaxation of the UES versus reduced laryngeal elevation in the remaining patient. Our findings demonstrated that HRIM using a simple methodology (i.e., pull-back of the catheter) detected pharyngeal residue through a simple analysis of the impedance contour pattern (linear vs. stasis). Furthermore, HRIM facilitated a comprehensive assessment of OPD mechanisms and recognition of subtle abnormalities not yet visible to the naked eye on VFSS.

ESD around the world: Asia

Endoscopic submucosal dissection (ESD) improves the quality of life of patients with early gastric cancer (EGC) and dysplasia by preserving gastric function. ESD in the treatment of EGC and dysplasia has become standard in Japan and Korea and is being developed and implemented in many major centers in Asia. With a well-designed prospective study, long-term outcomes of expanded criteria for endoscopic resection of EGC are expected to provide reliable indications for endoscopic treatment. Ongoing and novel clinical investigations of minimally invasive approaches and close collaboration between Western and Asian countries are expected to establish the best way to treat EGC.

Endoscopic Treatment of Various Gastrointestinal Tract Defects with an Over-the-Scope Clip: Case Series from a Tertiary Referral Hospital

Recently, increasingly invasive therapeutic endoscopic procedures and more complex gastrointestinal surgeries such as endoscopic mucosal resection, endoscopic submucosal dissection, and novel laparoscopic approaches have resulted in endoscopists being confronted more frequently with perforations, fistulas, and anastomotic leakages, for which nonsurgical closure is desired. In this article, we present our experiences with the use of over-the-scope clip (OTSC) for natural orifice transluminal endoscopic surgery (NOTES) closure, prevention of perforation, anastomotic leakages, and fistula closures. The OTSC is a valuable device for closing intestinal perforations and fistulas, for NOTES closure, and for the prevention of perforation after the excision of a tumor from the proper muscle layer. Furthermore, it seems to be quite safe to perform, even by endoscopists with little experience of the technique.

Clinical significance of the first surveillance colonoscopy after endoscopic early colorectal cancer removal

BACKGROUND/AIMS

We investigated the clinical significance of the first surveillance colonoscopy after endoscopic cancer removal.

METHODOLOGY

We conducted a retrospective cohort study at a single center. Patients diagnosed with early colon cancer after endoscopic removal (index colonoscopy) and who underwent surveillance colonoscopy within 1 year were enrolled. All visible lesions were removed during index colonoscopy. Polyps newly detected at surveillance colonoscopy considered as lesions missed during index colonoscopy were analyzed. We investigated risk factors for missing an advanced lesion.

RESULTS

In total, 139 patients diagnosed with early colorectal cancer were enrolled. Overall 774 lesions were removed during index colonoscopy and an additional 222 lesions were newly detected at the surveillance colonoscopy. The lesion miss rate during index colonoscopy was 22.3%. The miss rates for advanced adenoma and cancer were 11.4% and 3.6%, respectively. Total number of polyps during index colonoscopy was an associated risk factor for missing an advanced lesion (odds ratio 1.176, 95% interval 1.062-1.303).

CONCLUSIONS

Synchronous advanced neoplasms can be missed during endoscopic removal in patients with early colorectal cancer. Clinical significance of the first surveillance colonoscopy after endoscopic early colorectal cancer removal is detection of missed synchronous advanced neoplasms during index colonoscopy.

Accuracy of a scoring system for the differential diagnosis of common gastric subepithelial tumors based on endoscopic ultrasonography

OBJECTIVE

We aimed to validate a new scoring system for the differential diagnosis of gastric subepithelial tumors (SET) based on endoscopic ultrasonography (EUS) findings, and to determine its diagnostic yield for different gastric SET.

METHODS

Data of patients with gastric SET treated with endoscopic mucosal resection, endoscopic submucosal dissection or surgical resection from April 2001 to October 2012 at the Soonchunhyang University Hospital (Bucheon, Korea) were retrospectively reviewed. Four variables, including location, shape, layer of origin and echogenicity of the tumor on EUS were used to validate the new scoring system.

RESULTS

Among the 226 patients with gastric SET, 69 (30.5%) had gastrointestinal stromal tumors (GIST), 68 (30.1%) had ectopic pancreas and 35 (15.5%) had leiomyoma. Most GIST were located at the fundus and body (79.7%), whereas most leiomyomas were found at the cardia (80.0%). Ectopic pancreas was mostly found at the antrum (88.2%). GIST were mainly irregular and round in shape, while ectopic pancreas and lipoma were oval and leiomyomas were irregularly shaped on EUS. With a score range of 0-1 for leiomyoma, 2-3 for GIST, 4-6 for ectopic pancreas and 7-8 for lipoma, the sensitivity and specificity of the scoring system were 75.8% and 85.4% for GIST, 84.6% and 73.1% for ectopic pancreas, 75.9% and 99.5% for leiomyoma and 91.7% and 96.7% for lipoma, respectively.

CONCLUSIONS

The new scoring system was simple and relatively useful for predicting the histology of gastric SET without acquiring tissues. Prospective studies with large sample sizes are needed in the future.

Magnifying endoscopy for the diagnosis of specialized intestinal metaplasia in short-segment Barrett’s esophagus

AIM: To determine whether magnified observation of short-segment Barrett’s esophagus (BE) is useful for the detection of specialized intestinal metaplasia (SIM).

METHODS: Thirty patients with suspected short-segment BE underwent magnifying endoscopy up to × 80. The magnified images were analyzed with respect to their pit-patterns, which were simultaneously classified into five epithelial types [I (small round), II (straight), III (long oval), IV (tubular), V (villous)] by Endo’s classification. Then, a 0.5% solution of methylene blue (MB) was sprayed over columnar mucosa. The patterns of the magnified image and MB staining were analyzed. Biopsies were obtained from the regions previously observed by magnifying endoscopy and MB chromoendoscopy.

RESULTS: Three of five patients with a type V (villous) epithelial pattern had SIM, whereas 21 patients with a non-type V epithelial patterns did not have SIM. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of pit-patterns in detecting SIM were 100%, 91.3%, 92.3%, 60% and 100%, respectively (P = 0.004). Three of the 12 patients with positive MB staining had SIM, whereas 14 patients with negative MB staining did not have SIM. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of MB staining in detecting SIM were 100%, 60.9%, 65.4%, 25% and 100%, respectively (P = 0.085). The specificity and accuracy of pit-pattern evaluation were significantly superior compared with MB staining for detecting SIM by comparison with the exact McNemar’s test (P = 0.0391).

CONCLUSION: The magnified observation of a short-segment BE according to the mucosal pattern and its classification can be predictive of SIM.

Endoscopic submucosal dissection using a thulium laser: preliminary results of a new method for treatment of gastric epithelial neoplasia

BACKGROUND AND STUDY AIM

This study aimed to evaluate the feasibility of a novel laser system for endoscopic submucosal dissection (ESD) of gastric epithelial neoplasia.

PATIENTS AND METHODS

A total of 10 patients underwent ESD by a single expert endoscopist. A thulium 2-μm wavelength laser system was used for ESD procedures. Instead of using endoscopy knives, a 550-μm flexible silica fiber was inserted through the working channel of the endoscope.

RESULTS

In all patients, ESD was completed using only the thulium laser, without the need for endoscopy knives. The median total procedure time was 49 minutes (range 35 - 203). In 8 /10 patients (80 %), no active bleeding was observed during ESD. The final pathologic mapping revealed low-grade dysplasia (n = 4), differentiated adenocarcinoma (n = 5), and signet ring cell carcinoma (n = 1). Curative resection was achieved in 9 /10 patients (90 %). There were no significant complications, such as delayed bleeding or perforation.

CONCLUSIONS

The thulium laser system was feasible in ESD of gastric epithelial neoplasia.