Development of an E-learning System for the Endoscopic Diagnosis of Early Gastric Cancer: An International Multicenter Randomized Controlled Trial

Background

In many countries, gastric cancer is not diagnosed until an advanced stage. An Internet-based e-learning system to improve the ability of endoscopists to diagnose gastric cancer at an early stage was developed and was evaluated for its effectiveness.

Methods

The study was designed as a randomized controlled trial. After receiving a pre-test, participants were randomly allocated to either an e-learning or non-e-learning group. Only those in the e-learning group gained access to the e-learning system. Two months after the pre-test, both groups received a post-test. The primary endpoint was the difference between the two groups regarding the rate of improvement of their test results.

Findings

515 endoscopists from 35 countries were assessed for eligibility, and 332 were enrolled in the study, with 166 allocated to each group. Of these, 151 participants in the e-learning group and 144 in the non-e-learning group were included in the analysis. The mean improvement rate (standard deviation) in the e-learning and non-e-learning groups was 1·24 (0·26) and 1·00 (0·16), respectively (P < 0·001).

Interpretation

This global study clearly demonstrated the efficacy of an e-learning system to expand knowledge and provide invaluable experience regarding the endoscopic detection of early gastric cancer (R000012039).

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This report establishes that an e-learning system on the Internet can improve the diagnostic ability of endoscopists.

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Countless endoscopists worldwide can access the system to learn how to make an endoscopic diagnosis of early gastric cancer.

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The e-learning system could be modified to provide education regarding endoscopic diagnosis in other organs.

This is the first report to demonstrate how an e-learning system based on the Internet can improve the diagnostic ability of gastrointestinal endoscopists worldwide. There is no limit to the number of endoscopists who can access the system and benefit from this opportunity to learn how to make an endoscopic diagnosis of early gastric cancer. This e-learning system could be modified to provide education regarding endoscopic diagnosis in other organs such as the large intestine and the esophagus, as well as the stomach. It may contribute to human welfare and health by reducing the mortality from gastrointestinal cancer.

Predictive factors for initial treatment response after circumferential radiofrequency ablation for Barrett's esophagus with early neoplasia: a prospective multicenter study

BACKGROUND AND STUDY AIMS

Radiofrequency ablation (RFA) is safe and effective for the eradication of neoplastic Barrett's esophagus; however, occasionally there is minimal regression after initial circumferential balloon-based RFA (c-RFA). This study aimed to identify predictive factors for a poor response 3 months after c-RFA, and to relate the percentage regression at 3 months to the final treatment outcome.

METHODS

We included consecutive patients from 14 centers who underwent c-RFA for high grade dysplasia at worst. Patient and treatment characteristics were registered prospectively. "Poor initial response" was defined as < 50 % regression of the Barrett's esophagus 3 months after c-RFA, graded by two expert endoscopists using endoscopic images. Predictors of initial response were identified through logistic regression analysis.

RESULTS

There were 278 patients included (median Barrett's segment C4M6). In poor initial responders (n = 36; 13 %), complete response for neoplasia (CR-neoplasia) was ultimately achieved in 86 % (vs. 98 % in good responders; P < 0.01) and complete response for intestinal metaplasia (CR-IM) in 66 % (vs. 95 %; P < 0.01). Poor responders required 13 months treatment (vs. 7 months; P < 0.01) for a median of four RFA sessions (vs. three; P < 0.01). We identified four independent baseline predictors of poor response: active reflux esophagitis (odds ratio [OR] 37.4; 95 % confidence interval [CI] 3.2 - 433.2); endoscopic resection scar regeneration with Barrett's epithelium (OR 4.7; 95 %CI 1.1 - 20.0); esophageal narrowing pre-RFA (OR 3.9; 95 %CI 1.0 - 15.1); and years of neoplasia pre-RFA (OR 1.2; 95 %CI 1.0 - 1.4).

CONCLUSIONS

Patients with a poor initial response to c-RFA have a lower ultimate success rate for CR-neoplasia/CR-IM, require more treatment sessions, and a longer treatment period. A poor initial response to c-RFA occurs more frequently in patients who regenerate their endoscopic resection scar with Barrett's epithelium, and those with ongoing reflux esophagitis, neoplasia in Barrett's esophagus for a longer time, or a narrow esophagus.

Animal models for endoscopic training: do we really need them?

Gastrointestinal endoscopy currently includes many therapeutic methods that are technically challenging and frequently associated with a significant risk of complications. Several issues such as the limited number of clinical cases and practice in emergency situations, and technical difficulty may limit the opportunity for training, and increased exposure in more relaxed situations would be desirable. Moreover, providing the patient with the best possible standard of care is a must. Animal models are the most easily available simulators. Training in these models has been recommended for several complex techniques, among which hemostasis, endoscopic ultrasound, endoscopic retrograde cholangiopancreatography, and endoscopic submucosal dissection are reviewed here. Ex vivo models are much easier to set up and, from an ethical standpoint, they should be used for the initial step in training whenever possible before moving on to in vivo models. Although simulation with animal models has been the subject of a good number of studies, very few of them have evaluated the impact on clinical outcomes, and clearly more studies are needed. Nevertheless, available evidence does suggest that practicing on animal models has an influence on the learning curve and facilitates the acquisition of skills in the complex endoscopic techniques reviewed.

Effects of long-term cyclo-oxygenase 2 selective and acid inhibition on Barrett's oesophagus

BACKGROUND

There is an overexpression of cyclo-oxygenase 2 (COX-2) in Barrett's oesophagus (BO).

AIM

To determine the long-term effect of a COX-2 inhibitor on cellular mechanisms involved in BO.

METHODS

A randomized controlled trial was conducted in BO patients allocated to continue the usual proton pump inhibitor (PPI) alone treatment, or PPI combined with rofecoxib (25 mg/day) for 6 months. Cell proliferation index and COX-2 expression in BO glands was determined in biopsy specimens at baseline and after treatment. Cell apoptosis, cyclin D1, p53 and vascular endothelial growth factor (VEGF) expression was also explored in a subset of patients. Student-t test and the U-Mann-Whitney test were used for quantitative and ordinal variables.

RESULTS

Of 62 patients, 58 completed the study. A higher proportion of patients on rofecoxib + PPI exhibited a decrease in COX-2 expression compared to those treated with PPI alone, but cell proliferation index was not affected. Unlike PPI alone, rofecoxib + PPI was associated with an increase in the apoptotic cell index, a decrease in p53 cell staining and VEGF expression in mucosal vessels. No effect on low-grade dysplasia or cyclin D1 was observed.

CONCLUSIONS

The addition of rofecoxib to PPI therapy does not affect cell proliferation index in BO cells after 6 months of therapy, but does reduce COX-2 and VEGF expression and increases cell apoptosis.

Assessment of colorectal lesions using magnifying colonoscopy and mucosal dye spraying: can significant lesions be distinguished?

BACKGROUND AND STUDY AIMS

Assessing the nature of lesions at the time of colonoscopy is important, and magnifying colonoscopy allows examination of mucosal crypt patterns. In this study, we assessed mucosal crypt patterns to see whether we could predict the histological findings.

PATIENTS AND METHODS

This retrospective study of total colonoscopy using magnifying colonoscopy involved 4445 patients between December 1993 and July 1998 at the National Cancer Center Hospital East. The mucosal crypt patterns of 3438 lesions were observed under magnifying colonoscopy with 0.2% indigo carmine solution, and classified according to a modified Kudo classification (type I to V). After endoscopic or surgical resection (3291 cases and 147 cases, respectively), histopathological examination was performed.

RESULTS

The diagnostic accuracy of magnifying endoscopy for non-neoplastic lesions was 75% (117/157), for adenomatous polyps it was 94% (3006/3186), and for invasive carcinomas it was 85 % (81/95).

CONCLUSIONS

The combination of magnifying colonoscopy and dye spraying is helpful in determining the nature of colonic lesions as non-neoplastic, adenomas, or invasive carcinomas. Therefore it may be possible to determine, at the time of colonoscopy, which lesions require no treatment, which can be removed endoscopically, and which should be removed by surgery.

Colonoscopic polypectomy with cutting current: is it safe?

BACKGROUND

Coagulation and blended electrosurgical current are currently recommended for colonoscopic polypectomy, whereas pure cut current is believed to be associated with a higher risk of bleeding. However, the outcome of polypectomy performed with a cut current has not been evaluated in a large case series. Our objective was to study the incidence and nature of complications when polypectomy is performed with a pure cut current.

METHODS

Among 9555 colonoscopic examinations, polypectomy cases were retrospectively reviewed for complications. The electrosurgical current applied was always the cutting waveform.

RESULTS

Electrosurgical polypectomy using pure cut current was performed to remove 4735 lesions. Hemoclips were applied to the excision site after polypectomy to prevent bleeding in 12% of the cases. Hemorrhage occurred in 1.1% of the polypectomies (3.1% of patients). The incidence of bleeding with the different methods was snare polypectomy 0.9%, endoscopic mucosal resection 1.6%, "hot" biopsy 0.4%, and piecemeal polypectomy 7.3%. Bleeding was immediate in 66.1% of episodes and delayed in 33.9%. Patients with delayed postpolypectomy bleeding were significantly younger than those with immediate bleeding (50.5 and 64.7 years, respectively, p < 0.001). There was 1 case of transmural burn, but no perforations.

CONCLUSION

Polypectomy can be performed with pure cut current with a bleeding rate comparable to that seen with the use of coagulation or blended current, provided that hemoclip placement can be used readily. Expertise in hemoclip placement is advisable if this method of polypectomy is to be used.

Hemoclipping for postpolypectomy and postbiopsy colonic bleeding

BACKGROUND

Obtaining colonoscopic biopsies and polypectomy can result in hemorrhage. The most effective management of this complication has not been determined. The objective of this study was to evaluate the endoscopic hemoclip in postprocedural colonic bleeding.

METHODS

Among 9555 consecutive colonoscopies, cases of postprocedural colonic bleeding (postpolypectomy and postbiopsy) requiring treatment were retrospectively reviewed. Endoscopic hemoclipping was initially attempted in each case; the rate of hemostasis after hemoclipping, use of additional hemostatic methods, and clinical outcome (need for transfusion/hospitalization) were analyzed.

RESULTS

There were 72 cases of bleeding in which treatment was required (45 immediate postpolypectomy, 18 delayed postpolypectomy and 9 postbiopsy). Endoscopic hemostasis was achieved in all cases of immediate postpolypectomy and postbiopsy bleeding and in all but one of the cases with delayed postpolypectomy bleeding. A detachable snare was used in addition to hemoclips in 3 cases of delayed postpolypectomy bleeding. There were no episodes of recurrent bleeding, deaths or need for surgery related to bleeding.

CONCLUSION

Early endoscopic management of postprocedural bleeding by hemoclipping provides hemostasis in the great majority of cases.

Diagnosis of submucosal tumor of the upper GI tract by endoscopic resection

BACKGROUND

Submucosal tumors are frequent findings during endoscopy, although definitive diagnosis based on histologic confirmation presents some difficulties. The aim of this study was to evaluate the efficacy and safety of endoscopic resection based on endoscopic ultrasonography (EUS) findings to reach a definitive diagnosis of submucosal tumor.

METHODS

Fifty-four submucosal tumors of the upper gastrointestinal (GI) tract were included in this study. EUS was performed to determine the layer of origin and location of the lesion and to rule out malignancy. En bloc resection was attempted for lesions originating in the muscularis mucosa or submucosa. For tumors originating in the muscularis propria, we performed partial resection limited to the covering mucosa to expose the lesion and obtained a sample with standard biopsy forceps.

RESULTS

Sufficient samples were obtained in all 54 cases. There was no perforation. Bleeding occurred in only 5 cases (9%) and was easily managed with endoscopic hemostatic methods. EUS and pathologic findings coincided in 74.1% of cases (40 of 54). Benign lesions (leiomyoma, aberrant pancreas, and others) were predominant (52 of 54), although 2 small lesions were confirmed at pathologic study to be malignant (leiomyosarcoma and leiomyoblastoma).

CONCLUSIONS

Endoscopic resection based on EUS findings proved to be an effective and safe method to confirm the histologic diagnosis of submucosal tumor of the upper GI tract. Endoscopic resection should be considered a valuable choice for definitive management of benign submucosal tumors originating in the superficial layers.

Endoscopic management of Dieulafoy lesions of the stomach: a case study of 26 patients

BACKGROUND AND STUDY AIMS

We studied the clinical features and therapeutic outcome in patients with a diagnosis of Dieulafoy lesion.

PATIENTS AND METHODS

Twenty-six patients who had upper gastrointestinal bleeding from Dieulafoy lesions received endoscopic therapy. The clinical and endoscopic features, and the outcome of therapy, were analysed retrospectively.

RESULTS

Hemostasis was attempted by hemoclipping in 18 patients, heater probe in six patients and ethanol injection in two patients. The initial therapy was successful in 22 (84.6%) cases. Hemostasis was achieved with additional endoscopic therapy in three cases (11,5%). Surgical treatment was needed only in one case, owing to uncontrolled bleeding. One patient died during the hospital stay from a cause unrelated to the Dieulafoy lesion. There were no side effects related to endoscopic therapy. None of these patients presented with rebleeding from Dieulafoy lesions over a mean long-term follow-up of 36 months.

CONCLUSIONS

Bleeding from Dieulafoy lesions can be managed successfully by endoscopic methods, and these should be regarded as the first choice in their management. We emphasize the role of hemoclipping, a mechanical method, for the endoscopic treatment of these lesions.