Early Gastric Neoplasms Research Articles

Frozen Section Biopsy to Evaluation of Obscure Lateral Resection Margins during Gastric Endoscopic Submucosal Dissection for Early Gastric Cancer

PurposeTo determine the diagnostic utility of a frozen section biopsy in patients undergoing endoscopic submucosal dissection (ESD) for early gastric neoplasms with obscure margins even with chromoendoscopy using acetic acid and indigo carmine (AI chromoendoscopy).Materials and MethodsThe lateral spread of early gastric neoplasms was unclear even following AI chromoendoscopy in 38 patients who underwent ESD between June 2007 and May 2011. Frozen section biopsies were obtained by agreement of the degree of lateral spread between two endoscopists. Thus, frozen section biopsies were obtained from 23 patients (FBx group) and not in the other 15 patients (AI group).ResultsNo significant differences were observed for size, histology, invasive depth, and location of lesions between the AI and FBx groups. No false positive or false negative results were observed in the frozen section diagnoses. Adenocarcinoma was revealed in three patients and tubular adenoma in one, thereby changing the delineation of lesion extent and achieving free lateral margins. The rates of free lateral resection margins and curative resection were significantly higher in the FBx group than those in the AI group.ConclusionsFrozen section biopsy can help endoscopists perform more safe and accurate ESD in patients with early gastric neoplasm.

Clinical outcomes of ESD for early gastric neoplasms in elderly patients

Endoscopic submucosal dissection (ESD) is a standard treatment in Japan for early gastric neoplasms. With an increase in elderly population, the number of elderly patients in whom ESD performed has also steadily increased. The aim of study was to evaluate the effectiveness of and problems associated with ESD for early gastric neoplasms in elderly patients. Subjects were 514 patients (586 lesions) with early gastric neoplasms performed ESD at two institutions. The patients were classified into an elderly group (age ≥ 75 years) and a nonelderly group (age < 75 years). We compared the characteristics of patients and lesions, treatment results, ESD-related complications and prognosis between the two groups. The elderly group included 200 patients (229 lesions), and the nonelderly group included 314 patients (357 lesions). The incidences of underlying disease, such as hypertension and heart disease, and the rate of antiplatelet agents use were significantly higher in the elderly group. En bloc and curative resection rates were high in both groups. The bleeding rate was significantly higher in the elderly group. Residual disease or recurrence rates were very low in both groups. The death rate due to other diseases was significantly higher in the elderly group. This study demonstrates the efficacy of ESD in both elderly and nonelderly patients. However, we must be attentive to ESD-related bleeding, death caused by other diseases, and underlying diseases when we perform ESD in elderly patients.

T1610: Gastric Endoscopic Submucosal Dissection (ESD) With the Aid of a New Traction Method, the Clip-Band Technique: A Feasibility Study in a Porcine Model

ESD has proven to be useful for the treatment of early gastric neoplasms, but it is only used anecdotally in western countries because it is technically demanding and associated with a significant risk of perforation. Submucosal dissection, after having completed the circumferential incision, is the most challenging stage of this technique.

Successful outcomes of endoscopic resection for gastric adenomas and early cancers located on the pyloric ring (with video)

Endoscopic resection is difficult to perform in patients who have gastric neoplasms located on the pyloric ring, especially for lesions that extend from the pyloric area to the duodenal bulb, where it is difficult to retroflex the endoscope, and the risk of perforation is increased. To assess the results of endoscopic resection of early gastric neoplasms located on the pyloric ring. Case series. Tertiary-care referral center. This study involved 16 patients with 5 gastric adenomas and 11 early cancers that were located on the pyloric ring. After a retroflexion trial within the duodenum for evaluation of tumor extension from the pyloric area to the duodenal bulb, en bloc resection was attempted. Endoscopic submucosal dissection was attempted at the duodenal bulb with an endoscope retroflexed for cases of duodenal invasion. The curative resection rate, en bloc resection rate, and complications were determined. The success rate of retroflexion within the duodenum was 88% (14 of 16). The curative resection rate was 81.3% (13 of 16), and the en bloc resection rate was 75% (12 of 16). En bloc resection was possible for 3 of 4 (75%) cases of duodenal bulb extension. Major procedure-related complications were not encountered. Small number of patients. Endoscopic resection appears to be a feasible and effective treatment for early gastric neoplasms located on the pyloric ring, including lesions that extend from the pyloric area to the duodenal bulb.

A Comparison of Outcomes of Endoscopic Submucosal Dissection (ESD) For Early Gastric Neoplasms Between High-Volume and Low-Volume Centers: Multi-Center Retrospective Questionnaire Study Conducted by the Nagano ESD Study Group

Outcomes of endoscopic submucosal dissection (ESD) for early gastric neoplasms at low-volume centers have been unknown, because all previous reports have studied in advanced single centers. The aim of this study was to compare ESD outcomes between high- and low-volume centers. A retrospective questionnaire survey was conducted and 30 centers (96.8%) responded. The complete en-bloc resection rate (CERR) and the incidence of complications were analyzed. Early gastric cancer (EGC) was divided into three categories on the basis of pathological diagnosis-standard indication (SI), expanded indication (EI) and out-of-indication (OI). A total of 703 early gastric neoplasms (586 EGCs, 117 gastric adenomas) were treated with ESD from January to December 2005. The institutions that treated more than 30 cases a year were classified as high-volume centers, and those with less than 30 cases, low-volume centers. In SI, the CERRs at high- and low-volume centers were 92.1% and 91.1%, in EI, CERRs were 86.2% and 82.6% and in OI, CERRs were 80.3% and 88.0%. The perforation rates at high- and low-volume centers were 3.6% and 4.7%. The intra-operative bleeding rates at high- and low-volume centers were 0.26% and 0%, while the delayed bleeding rates were 0% and 0.63%. There were no significant difference in the outcomes of ESD for early gastric neoplasms between high- and low volume centers.

Characteristics of Synchronous Early Gastric Neoplasm Which Had Not Been Realized During First Endoscopic Resection

Background and Aim: Endoscopic resection (ER) is an established therapeutic method of early gastric neoplasm. However, detection of missed lesions is a main problematic situation during short-term surveillance after ER. Another missed synchronous neoplasm is common cause of recurrence gastric neoplasm after endoscope resection. Aim of this study was to investigate the endoscopic characteristics of the multiple synchronous early gastric neoplasms. Patients and Methods: From Sep 2006 to Sep 2008, we retrospectively reviewed the medical records of 195 patients with early gastric neoplasms (total 240 lesions) who had been managed by EMR or ESD at our tertiary endoscopic center. Cases with the synchronous lesions (46 multiple synchronous lesions in 21 patients, group A) were compared with those without synchronous lesions (174 solitary lesions in 174 patients, group B) with regard to macroscopic classification, size, histologic type, location. Results: The incidence of synchronous gastric neoplasm was as high as 10.7% (21/195 patients). A total of twenty-three lesions were newly detected during the follow-up endoscopic examination after the first ER (mean 4.6 months). Predominant location was antrum in both groups. Adenoma was predominant type of neoplasm in both groups. Surface nodularity was more common in B group (55.7% vs 22.7%, p < 0.01). Macroscopically flat lesion was relatively more common in group A (23.9% vs. 13.2%, p < 0.01). In group A, 90% of main and accessory lesion was located in same or adjacent region. In 23 newly detected neoplasms, histologic type of new lesion was not different from previous lesion. Size of new lesion was smaller than previous lesion, but there was no statistical significance (p = 0.054). Macroscopically elevate lesion was more common in previous lesion (84.6%), but flat lesion was more common in new lesion (60%) (p < 0.01). Conclusion: Synchronous lesions are not unusual in patients with early gastric neoplasms, and half of them might be missed by first ER. Small and flat lesion can be missed easily even if it present in adjacent region. To avoid missing lesions during the first ER, endoscopists should pay special attention to find any possible synchronous lesions at index endoscopy, which could establish an ER as a more complete therapeutic method of early gastric neoplasm.

Therapeutic outcomes in 1000 cases of endoscopic submucosal dissection for early gastric neoplasms: Korean ESD Study Group multicenter study

The technique of endoscopic submucosal dissection (ESD) was introduced to be able to obtain en bloc specimens of large early GI neoplasms. The drawback of ESD is its technical difficulty, which, consequently, is associated with a higher rate of complication and which requires advanced endoscopic techniques and a long procedure time. To assess the therapeutic outcome of ESD by expert endoscopists who have at least 3 years' experience of EMR in Korea. A retrospective, multicenter study. From January 2006 to June 2007, 1000 early gastric cancers in 952 patients (502 men, 450 women; mean age 62.1 years, range 43-90 years) were treated by using ESD at 6 Korean ESD study group (KESG)-related university hospitals in Korea. We performed ESD procedures with typical sequences (marking, incision, and submucosal dissection). The rate of en bloc resection, incidence of complication, and length of procedure. Predetermined factors (various endoscopic and final pathologic features) for these outcomes. The rates of en bloc resection, complete en bloc resection, vertical incomplete resection, and piecemeal resection were 95.3%, 87.7%, 1.8%, and 4.1%, respectively. The rates of delayed bleeding, significant bleeding, perforation, and surgery related to complication were 15.6%, 0.6%, 1.2%, and 0.2%, respectively. The mean procedure time was 47.8 +/- 38.3 minutes. The rates of en bloc resection differed significantly in relation to the location of the lesions (upper portion vs middle portion vs lower portion of the stomach, 88.6% vs 95.2% vs 96.0%, respectively; P = .02), presence of a scar (no vs yes, 96.0% vs 89.5%, respectively; P = .002), and histologic type (low-grade adenoma vs high-grade adenoma vs differentiated early gastric cancer vs undifferentiated early gastric cancer, 95.8% vs 94.6% vs 96.2% vs 83.8%, respectively; P = .007). The rates of delayed bleeding differed significantly in relation to location (upper portion vs lower portion of the stomach, 28.6% vs 13.8%, respectively; P = .003), the size of the tumor (>40 mm vs <20 mm, 28.6% vs 13.7%, respectively; P = .009), recurrent lesion (29.4% vs 15.1%, respectively; P = .024), and macroscopic type (flat vs elevated, 18.8% vs 12.4%, respectively; P = .047). Factors related to the longer procedure time were location (upper portion vs lower portion of the stomach, 64.8 vs 44.1 minutes, respectively; P < .001), the size of the tumor (>40 mm vs < 20 mm, 67.1 vs 42.0 minutes, respectively; P < .001), the presence of ulcer (54.6 vs 46.8 minutes; P < .045), and the presence of a scar (69.2 vs 45.0 minutes; P < .001). ESD is an effective and safe therapy in the management of early gastric neoplasms. Endoscopists have to accept the need for advanced endoscopic techniques for performing ESD in the case of large lesions, scar lesions, undifferentiated cancers, or for the lesions in the upper portion of the stomach. Endoscopists require more experience to decrease complications in patients who have a large or recurrent lesion in the upper portion of the stomach; these lesions also take more time to complete the ESD procedure.

A New Classification of Narrow Band Imaging Magnification Endoscopy (NBI-ME) for Early Gastric Neoplasms (EGN) Before Endoscopic Submucosal Resection (ESD)

Background: Some studies suggest that NBI-ME enhances endoscopic diagnosis of eGN compared to white light (WL). However, most NBI-ME classifications are too cumbersome for clinical use. Aims: To assess the utility of a simplified NBI-ME classification system for predicting the histology and endoscopic margins of eGN. Methods: 51 pts with eGN without ulceration were examined using a 80X magnifying gastroscope (GIF-Q240Z) and Evis-Lucera 260 processor (Olympus, Tokyo, Japan) using both WL and NBI-ME, before ESD. Gastric pit patterns, capillary networks, and tumor demarcation lines were carefully observed in 58 lesions: 44 well differentiated cancer (WD), 7 poorly differentiated cancers (PD), 7 dysplasia (DY). Gastric pit patterns: tubular, distorted, mixed (tubular dominant or distorted dominant), unclassified, and normal. Vascular patterns: capillary network pattern (CNP), abnormal tumor vessels (ATV), mixed, and normal. Demarcation lines: well demarcated, no demarcation, and equivocal. Endoscopic imaging quality score: 3- NBI-ME better than WL; 2- NBI-ME equal to WL; 1- WL better than NBI-ME. To assess its clinical utility, the pathologic complete resection (CR) rate of pts who had ESD using NBI-ME was compared with those who had ESD using WL. The pathologist was blinded to the imaging modality. Results: Pit patterns: WF: tubular pattern (6.8%), distorted (25%), mixed tubular dominant (36.3%) and mixed distorted dominant (27.3%) and unclassified (4.5%). PD: distorted (57.1%), mixed tubular dominant (14.2%) and mixed distorted dominant (28.5%). DY: tubular pattern (42.8%), distorted (28.5%), mixed tubular dominant (14.3%) and normal (14.3%). Vascular patterns: WD: CNP (2.2%), abnormal tumor vessels (81.8%), and mixed (9%), and normal (6.8%). PD: CNP (14.3%), abnormal tumor vessels (85.7%), and mixed (0%), and normal (0%). DY: CNP (28.6%), ATV (57.1%), and normal (14.2%). Demarcation lines: WD: well demarcated: (77.2%), not demarcated (15.9%), equivocal (6.8%). PD: well demarcated (28.5%), not demarcated (42.8%), equivocal (28.5%). DY: well demarcated (85.7%), not demarcated (14.2%), equivocal (0). The pathologic CR rate was 84.3% (177/210) using WL and 95.9% (55/58) using NBI-ME. The image quality score of NBI-ME was 2.89 ± 0.3. Conclusions: 1. most WD (88%) and PD (86%) cancers have abnormal tumor vessels, 2. Dysplastic lesions (86%) and WD cancers (77%), but not PD cancers, generally have endoscopically visible demarcation lines, 3. a tubular pits pattern suggests dysplasia, whereas a distorted pattern suggests PD. The ESD pathologic complete resection rate is marginally improved (10%) when using this simplified NBI-ME classification system.

Therapeutic Outcome in 1000 Cases of Endoscopic Submucosal Dissection (ESD) for Early Gastric Neoplasms; Korean ESD Study Group (KESG) Multi-Center Study

Therapeutic Outcome in 1000 Cases of Endoscopic Submucosal Dissection (ESD) for Early Gastric Neoplasms; Korean ESD Study Group (KESG) Multi-Center Study

A Multicenter Retrospective Study of Endoscopic Submucosal Dissection for Early Gastric Neoplasms-The Nagano ESD Study Group Report

Background and Study Aim: Recently endoscopic submucosal dissection (ESD) for early gastric neoplasms became widespread in Japan. However outcomes of ESD had not been distinct because previous reports had limitations of advanced single center studies. Aim of this study is to clarify the standardized outcomes of ESD for early gastric neoplasms in a multicenter questionnaire study. Methods: A questionnaire was conducted by the Nagano ESD study group for 31 centers in Nagano prefecture in Japan and 30 centers (96.8%) replied. Contents of the questionnaire included outcomes and complications. Early gastric cancer (EGC) was divided into three categories based on pathological diagnosis following gastric cancer treatment guidelines of the Japanese gastric cancer association: Standard indication(SI); differentiated adenocarcinoma, intramucosal cancer ≦20 mm in size, Expanded indication (EI); differentiated adenocarcinoma, intramucosal cancer regardless of tumor size without ulcer findings, intramucosal cancer ≦30 mm in size with ulcer findings, minute submucosal cancer (sm1) ≦30 mm in size, Out of indication (OI); except for the above. Results: A total of 715 early gastric neoplasms (586 EGCs, 129 gastric adenomas) were treated in all centers with ESD from January to December 2005. The rates of en-bloc and cut end negative resection of EGCs of SI, EI and OI were 91.6% (295/322), 84.8% (151/178) and 81.3% (71/86), respectively. The reasons for impossibility of en-bloc and cut end negative resection were as follows; In SI group, piecemeal resection accounted for 29.6% (8/27), positive lateral margin 59.2% (16/27), positive horizontal margin 11.1% (3/27); in EI group, piecemeal resection 59.2%(16/27), positive lateral margin 29.6% (8/27), positive horizontal margin 11.1% (3/27); in OI group, piecemeal resection 20.0%(3/15), positive lateral margin 33.3% (5/15), positive horizontal margin 46.7% (7/15). Incidence of perforation was 4.06% (29/715). Incidence of bleeding that required blood transfusion was 0.28% (2/715). All complications were managed endoscopically and there was no procedure related mortality. Conclusions: In this multicenter retrospective study, standardized outcomes of ESD were excellent and complications were tolerable in comparison with advanced single center reports.

The Efficacy of Endoscopic Submucosal Dissection for Early Gastric Neoplasms Using Insulated-Tip Diathermic Knife

The Efficacy of Endoscopic Submucosal Dissection for Early Gastric Neoplasms Using Insulated-Tip Diathermic Knife

Introduction: What Should We Do Now about H. pylori?

Cancer is widely seen as a problem of industrialized countries, reflecting the consequences of affluent lifestyles and exposure to chemical carcinogens, such as those in tobacco smoke. In low- and middle-income countries, where infectious diseases and child survival are dominant concerns, cancer

Hypermethylation of the hMLH1 gene promoter is associated with microsatellite instability in early human gastric neoplasia.

A significant portion of gastric cancers exhibit defective DNA mismatch repair, manifested as microsatellite instability (MSI). High-frequency MSI (MSI-H) is associated with hypermethylation of the human mut-L homologue 1 (hMLH1) mismatch repair gene promoter and diminished hMLH1 expression in advanced gastric cancers. However, the relationship between MSI and hMLH1 hypermethylation has not been studied in early gastric neoplasms. We therefore investigated hMLH1 hypermethylation, hMLH1 expression and MSI in a group of early gastric cancers and gastric adenomas. Sixty-four early gastric neoplasms were evaluated, comprising 28 adenomas, 18 mucosal carcinomas, and 18 carcinomas with superficial submucosal invasion but clear margins. MSI was evaluated using multiplex fluorescent PCR to amplify loci D2S123, D5S346, D17S250, BAT 25 and BAT 26. Methylation-specific PCR was performed to determine the methylation status of hMLH1. In two hypermethylated MSI-H cancers, hMLH1 protein expression was also evaluated by immunohistochemistry. Six of sixty-four early gastric lesions were MSI-H, comprising 1 adenoma, 4 mucosal carcinomas, and 1 carcinoma with superficial submucosal invasion. Two lesions (one adenoma and one mucosal carcinoma) demonstrated low-frequency MSI (MSI-L). The remaining 56 neoplasms were MSI-stable (MSI-S). Six of six MSI-H, one of two MSI-L, and none of thirty MSI-S lesions showed hMLH1 hypermethylation (P<0.001). Diminished hMLH1 protein expression was demonstrated by immunohistochemistry in two of two MSI-H hypermethylated lesions. hMLH1 promoter hypermethylation is significantly associated with MSI and diminished hMLH1 expression in early gastric neoplasms. MSI and hypermethylation-associated inactivation of hMLH1 are more prevalent in early gastric cancers than in gastric adenomas. Thus, hypermethylation-associated inactivation of the hMLH1 gene can occur early in gastric carcinogenesis.