Attempted endoscopic en bloc resection of mucosal and submucosal tumors using insulated-tip knives: a pilot series

Laparoscopic-endoscopic rendez-vous resection of iuxta-cardial gastric GIST

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract and they often require a surgical removal. Gastrointestinal stromal tumors can originate from any part of the gastrointestinal tract but gastric location is the most common. In the past the risk of rupture of pseudocapsula and peritoneal dissemination have discouraged surgeons from making a minimally invasive surgical treatment. Recently laparoscopic wedge resection has been proposed. Performance of this mini-invasive technique is however difficult in some gastric location of gastrointestinal stromal tumors, such as iuxta-cardial region. The Authors report and discuss a new technique they used to remove a gastrointestinal stromal tumor located just below the cardia, using a rendez-vous endoscopic and laparoscopic technique.

Prospective, randomized comparison of a prototype endoscope with deflecting working channels versus a conventional double-channel endoscope for rectal endoscopic submucosal dissection in an established experimental simulation model (with video)

BACKGROUND

A prototype endoscope was designed to improve visualization and dissection of tissue with the use of 2 working channels with different deflections.

OBJECTIVE

To evaluate the efficacy and operability of a prototype endoscope in comparison with a conventional double-channel endoscope for rectal endoscopic submucosal dissection (ESD).

DESIGN

Randomized, prospective, controlled, ex vivo study.

SETTING

Academic medical center.

METHODS

A total of 80 standardized artificial lesions measuring 3 × 3 cm were created approximately 5 cm from the anal verge in fresh ex vivo porcine colorectal specimens. Two endoscopists each completed 20 cases with the prototype endoscope and 20 cases with the conventional endoscope.

MAIN OUTCOME MEASUREMENTS

An independent observer recorded procedure time, specimen size, en bloc resection, and perforation rate.

RESULTS

For the ESD novice, the mean submucosal dissection time (10.5 ± 3.8 vs 14.9 ± 7.3 minutes; P = .024) and total procedure time (18.1 ± 5.2 vs 23.6 ± 8.2 minutes; P = .015) were significantly shorter in the prototype group in comparison with the conventional group. For the ESD expert, there was no significant difference between the mean circumferential resection, submucosal dissection, and total procedure time (prototype group 14.2 ± 6.0 minutes, conventional group 14.2 ± 8.8 minutes; P = .992). The overall perforation and en bloc resection rates were not significantly different between groups.

LIMITATIONS

Ex vivo study.

CONCLUSION

In this ex vivo prospective comparison study, there was a technical advantage for the ESD novice with the prototype endoscope that resulted in a shorter procedure time, which was not observed for cases performed by the ESD expert.

Endoscopic submucosal dissection in the treatment of gastric submucosal tumors: results from a retrospective cohort study

BACKGROUND

A submucosal tumor (SMT) of the stomach, which is an occasional finding during routine upper gastrointestinal endoscopy, may pose diagnostic and therapeutic challenges.

METHODS

To assess whether endoscopic submucosal dissection (ESD) is a feasible approach to definitively cure SMTs, the authors performed a retrospective cohort study with two endoscopic italian centers.

RESULTS

The study consisted of 20 patients with SMTs who underwent ESD. The patients underwent ESD and were followed up by endoscopy. We analyzed complete resection rate, frequency of complications, and survival. The overall rate of R0 resection was 90 % (18/20), with two endoscopic failures, one for a submucosal tumor and one for a neoplasm deeply infiltrating the proper muscle layer. The median procedure time was 119.1 min (range 40-240 min). The median size of the resected specimens was 29 mm (range 15-60 mm). Perforation occurred in 3 patients; all were treated conservatively. There were no cases of severe bleeding. Based on histopathological findings, 6 cases of ectopic pancreas, 1 of ectopic spleen, 3 of leiomyoma, and 10 of gastrointestinal stromal tumor (GIST) were diagnosed. Complete resection was obtained in all GIST cases. Among the 10 GIST cases treated by ESD, no death occurred: the 5-year disease-specific survival rate was 100 %.

CONCLUSIONS

The high success rate of 90 % and the low incidence of complications should indicate ESD is the correct diagnostic and definitive treatment in selected patients.

Indications of endoscopic submucosal dissection for symptomatic benign gastrointestinal subepithelial or carcinoid tumors originating in the submucosa

Endoscopic submucosal dissection (ESD) for upper gastrointestinal (GI) subepithelial tumors (SETs) originating in the muscularis propria (MP) layer is associated with numerous issues regarding secure closure and measures against accidental perforation. However, symptomatic benign GI SETs or carcinoid tumors originating in the submucosa (SM) may be safely resected en-bloc using ESD. In this study, the feasibility and safety of ESD as a novel method for endoscopic resection for such GI SETs revealed on endoscopic ultrasonography (EUS) was investigated. A total of 12 consecutive cases of patients with symptomatic benign SETs (n=3; 1 esophageal hemangioma and 2 gastric lipomas) or small carcinoid tumors (n=9; <10 mm, with an extremely low risk of metastasis) originating in the SM as determined on EUS, between March, 2009 and April, 2013, were retrospectively reviewed. The lesions were resected by ESD after confirming that the tumors originated from the SM. The complication rate following en-bloc resection was also determined. En-bloc resection was achieved in all 12 cases, the mean procedure time was 45 min (range, 20-120 min) and no complications occurred intra- or postoperatively. There was no tumor recurrence or disease-related mortality reported during the follow-up period (median follow-up time, 13.4 months). Histopathological curative resection was achieved with ESD without complications in all 9 cases with carcinoid tumors. Therefore, if EUS reveals a SET originating in the SM without infiltration of the MP and resection is indicated due to the presence of abdominal symptoms, ESD may be a feasible option for diagnostic treatment with minimal invasiveness. However, larger-scale prospective studies are required to establish the feasibility and safety of this procedure.

Endoscopic resection for gastrointestinal neuroendocrine tumors

Gastrointestinal (GI) and neuroendocrine tumors (NETs) can be treated by mini-invasive endoscopic resection when localized in the superficial layers of the bowel wall and their size is <20 mm. Endoscopic diagnosis of NETs is usually incidental or suspected after clinical, laboratory or imaging findings. Endoscopic mucosal resection is the most commonly used technique for NET removal, endoscopic submucosal dissection is indicated in selected cases, while papillectomy is feasible for ampullary lesions. Histopathologic assessment of the resection margin (circumferential and deep) is important for staging. Incidence of endoscopic mucosal resection-/endoscopic submucosal dissection-related complications for removal of GI NETs are similar to those reported for other GI lesions. Endoscopic follow-up is based on histopathologic characteristics of the resected NETs and its site. NETs >20 mm in size, with penetration of the muscle layer and/or serosa are at high risk for metastases and surgical approach is recommended when feasible.

Randomized study of two endo-knives for endoscopic submucosal dissection of esophageal cancer

OBJECTIVES

Settings for endoscopic submucosal dissection (ESD) of esophageal cancer have not been standardized, and no studies have directly compared ESD devices in humans.

METHODS

We conducted a randomized study to compare the performances of two different endo-knives, the Flush knife and Mucosectom, for esophageal ESD in 48 lesions. All procedures were initiated by two endoscopists, who were assisted by senior endoscopists with verbal advice. In the Flush-knife group, mucosal incision with a 2-mm Flush knife was followed by submucosal dissection using a 1-mm Flush knife. In the Mucosectom group, mucosal incision with a 2-mm Flush knife was followed by submucosal dissection with a Mucosectom. The primary outcome variable was the procedure time required for submucosal dissection. The secondary outcome variables were total procedure time, self-completion rates, and adverse events.

RESULTS

Total procedure time in the Mucosectom group was significantly shorter than in the Flush-knife group (57±21 vs. 83±27 min, respectively; P<0.001). The submucosal-dissection time in the Mucosectom group was significantly shorter than in the Flush-knife group (40±18 vs. 61±23 min, respectively; P<0.001). The self-completion rate in the Mucosectom group was slightly higher than in the Flush-knife group, but the difference was not significant (91.7% vs. 75%, respectively; P=0.25). One perforation and one postoperative bleeding occurred in the Flush-knife group, both of which were treated successfully by endoscopic treatment.

CONCLUSIONS

The Mucosectom reduced the procedure and submucosal-dissection times of esophageal ESD, without increasing adverse events.

Effects of medical adhesives in prevention of complications after endoscopic submucosal dissection

AIM: To evaluate the use of medical adhesive spray in endoscopic submucosal dissection (ESD).

METHODS: Patients who underwent ESD between January 2009 and June 2012 (n = 173) were enrolled in the prospective randomized study. Two patients undergoing surgery due to severe intraoperative hemorrhage and failed hemostasis were excluded, and the remaining 171 patients were randomly divided into two groups: group A (medical adhesive group, n = 89) and group B (control group, n = 82). In group A, a medical adhesive spray was evenly applied after routine electrocoagulation and hemostasis using hemostatic clip after ESD. Patients in group B only treated with routine wound management. Intraoperative and postoperative data were collected and compared.

RESULTS: In all 171 patients, ESD was successfully completed. There was no significant difference in the average treatment time between groups A and B (59.4 min vs 55.0 min, respectively). The average length of hospital stay was significantly different between group A and B (8.89 d vs 9.90 d, respectively). The incidence of intraoperative perforation was 10.1% in group A and 9.8% in group B, and was not significantly different between the two groups. In all cases, perforations were successfully managed endoscopically and with conservative treatment. The incidence of postoperative delayed bleeding in group A was significantly lower than that in group B (0.00% vs 4.88%, respectively).

CONCLUSION: ESD is an effective minimally invasive treatment for gastrointestinal precancerous lesions or early-stage gastrointestinal cancer. Medical adhesive spray is effective in preventing delayed bleeding after ESD, and can thus reduce the average length of hospital stay.

A new instrument for endoscopic submucosal dissection (with videos)

BACKGROUND

Although it is effective for treatment of early neoplasms, endoscopic submucosal dissection (ESD) can be technically demanding and time consuming. Furthermore, use of multiple instruments is often mandatory for performing various steps associated with the procedure.

OBJECTIVE

To design, create, and evaluate a new instrument for ESD.

DESIGN

Feasibility study by using an acute porcine model.

SETTING

Center for preclinical research, university hospital.

SUBJECTS

This study involved 6 female pigs.

INTERVENTION

Gastric ESDs including circumferential incision and coagulation of bleeding vessels were performed by using a single device. Incision was done with the prototype instrument in a closed position by using cutting current. Submucosal dissection was performed by using an approach with 4 steps: (1) open forceps, (2) grasp submucosal fibers, (3) elevate and retract tip to avoid contact with muscle layer, (4) dissect fibers by using cutting current. Bleeding was terminated with the same instrument by grasping vessels and applying coagulation current.

MAIN OUTCOME MEASUREMENTS

Overall feasibility and performance, time needed to achieve complete resection.

RESULTS

The new instrument was useful for performing all single steps needed. Mean (± standard deviation [SD]) time needed for the whole procedure was 48.5 ± 9.9 minutes. Mean (± SD) time needed for incision and dissection was 37.8 ± 8.8 minutes.

LIMITATIONS

Animal study, limited number.

CONCLUSION

The new instrument has potential advantages in comparison with standard instruments used for ESD. Incision, dissection, and coagulation of vessels can be performed with a single instrument, and the technique of lifting submucosal fibers during dissection potentially decreases the risk of perforation. Comparison studies with larger gastric lesions treated with standard ESD techniques are needed.

Development and clinical usability of a new traction device "medical ring" for endoscopic submucosal dissection of early gastric cancer

Background

Although various traction devices exist for endoscopic submucosal dissection (ESD), the effects of the material used in the devices on the human body has not been considered. Moreover, there has been no report on a device that facilitates dissection both on the oral and anal side of the lesion. We made a traction device that has no deleterious effects on the body and is noninvasive, easy to use, and enables a bilateral approach in ESD. We report the process of its creation and a prospective evaluation of its usage in actual ESD procedures.

Methods

This study is prospective case control study. Thirty-seven patients for whom the device would be used were consecutively and prospectively enrolled (device used group). Control subjects in whom the device would not be used and who had lesions matched for size and location with those of the device used group were randomly selected (device not used group). Both groups were classified into three subgroups according to treatment difficulty: group A: easy; group B: intermediate; and group C: difficult. The dissection time per cm² in each group was examined.

Results

Dissection times in the device not used group/device used group were as follows: group A, 5.8/2.1 min/cm² (p < 0.01); group B, 6.1/3.8 min/cm² (p < 0.05); and group C, 7.9/3.6 min/cm² (p < 0.01), respectively.

Conclusions

The newly developed medical ring was shown to be feasible and safe and allowed excellent visualization through suitable tension and facilitated rapid gastric ESD.

Electronic supplementary material

The online version of this article (doi:10.1007/s00464-013-2887-6) contains supplementary material, which is available to authorized users.

Function-preserving gastrectomy for early gastric cancer

The number of early gastric cancer (EGC) cases has been increasing because of improved diagnostic procedures. Applications of function-preserving gastric cancer surgery may therefore also be increasing because of its low incidence of lymph node metastasis, excellent survival rates, and the possibility of less-invasive procedures such as laparoscopic gastrectomy being used in combination. Pylorus-preserving gastrectomy (PPG) with radical lymph node dissection is one such function-preserving procedure that has been applied for EGC, with the indications, limitations, and survival benefits of PPG already reported in several retrospective studies. Laparoscopy-assisted proximal gastrectomy has also been applied for EGC of the upper third of the stomach, although this procedure can be associated with the 2 major problems of reflux esophagitis and carcinoma arising in the gastric stump. In the patient with EGC in the upper third of the stomach, laparoscopy-assisted subtotal gastrectomy with a preserved very small stomach may provide a better quality of life for the patients and fewer postoperative complications. Finally, the laparoscopy endoscopy cooperative surgery procedure combines endoscopic submucosal dissection with laparoscopic gastric wall resection, which prevents excessive resection and deformation of the stomach after surgery and was recently applied for EGC cases without possibility of lymph node metastasis. Function-preserving laparoscopic gastrectomy is recommended for the treatment of EGC if the indication followed by accurate diagnosis is strictly confirmed. Preservation of remnant stomach sometimes causes severe postoperative dysfunctions such as delayed gastric retention in PPG, esophageal reflux in PG, and gastric stump carcinoma in the remnant stomach. Moreover, these techniques present technical difficulties to the surgeon. Although many retrospective studies showed the functional benefit or oncological safety of function-preserving gastrectomy, further prospective studies using large case series are necessary.

Recent developments in gastric endoscopic submucosal dissection: towards the era of endoscopic resection of layers deeper than the submucosa

With technical advances in endoscopic submucosal dissection (ESD), several variations of endoscopic procedure derived from ESD and fusion procedures of endoscopy and laparoscopy for upper gastrointestinal submucosal tumor and cancer have recently been developed. The former includes endoscopic muscularis dissection (EMD), submucosal endoscopic tumor resection (SET), endoscopic submucosal tunnel dissection (ESTD) and endoscopic full-thickness resection (EFTR), and the latter includes laparoscopic and endoscopic cooperative surgery (LECS), laparoscopy-assisted endoscopic full-thickness resection (LAEFR), and laparoscopic lymphadenectomy without gastrectomy following ESD. In the present article, recent developments in gastric ESD and advanced procedures derived from ESD are discussed.

Endoscopic resection (endoscopic mucosal resection/ endoscopic submucosal dissection) for early gastric cancer

Endoscopic resection of early gastric cancer is a well-established standard therapy in Japan and Korea, and is increasingly used in other countries. Endoscopic resection should be curative for patients, and safe, easy and effective not only for patients, but also for endoscopists. Endoscopic submucosal dissection (ESD) is superior to standard endoscopic mucosal resection (EMR) as it is designed to provide en bloc R0 resection regardless of size and/or location. Correct pathological assessment of en bloc resected specimens is crucial for accurate diagnosis and patient stratification for the risk of metastasis. Outcome studies in Japan and Korea, countries with the highest incidence of gastric cancer, have shown that ESD is efficacious in leading to a good long-term outcome; however, ESD requires an experienced endoscopist with a high skill level. Expanded indications for endoscopic resection have been proposed, especially after large en bloc resection have been accomplished using ESD. The use of ESD could be of huge benefit for the management of gastrointestinal superficial neoplasms. However, for ESD to become a viable therapeutic option, it requires close and supportive working relationships between endoscopists, pathologists and surgeons.

Can endoscopic submucosal dissection be safely performed in a smaller specialized clinic?

AIM: To investigate whether endoscopic submucosal dissection (ESD) can be safely performed at small clinics, such as the Shirakawa Clinic.

METHODS: One thousand forty-seven ESDs to treat gastrointestinal tumors were performed at the Shirakawa Clinic from April 2006 to March 2011. The efficacy, technical feasibility and associated complications of the procedures were assessed. The ESD procedures were performed by five endoscopists. Sedation was induced with propofol for esophagogastorduodenal ESD.

RESULTS: One thousand forty-seven ESDs were performed to treat 64 patients with esophageal cancer (E), 850 patients with gastric tumors (G: 764 patients with cancer, 82 patients with adenomas and four others), four patients with duodenal cancer (D) and 129 patients with colorectal tumors (C: 94 patients with cancer, 21 patients with adenomas and 14 others). The en bloc resection rate was 94.3% (E: 96.9%, G: 95.8%, D: 100%, C: 79.8%). The median operation time was 46 min (range: 4-360 min) and the mean size of the resected specimens was 18 mm (range: 2-150 mm). No mortal complications were observed in association with the ESD procedures. Perforation occurred in 12 cases (1.1%, E: 1 case, G: 9 cases, D: 1 case, C: 1 case) and postoperative bleeding occurred in 53 cases (5.1%, G: 51 cases, D: 1 case, C: 1 case); however, no case required either emergency surgery or blood transfusion. All of the perforations and postperative bleedings were resolved by endoscopic clipping or hemostasis. The other problematic complication observed was pneumonia, which was treated with conservative therapy.

CONCLUSION: ESD can be safely performed in a clinic with established therapeutic methods and medical services to address potential complications.

Endoscopic submucosal dissection for gastric neoplasm in patients with co-morbidities categorized according to the ASA Physical Status Classification

BACKGROUND

Endoscopic submucosal dissection (ESD) has come to be widely performed for reduced invasiveness; however, its safety in patients with co-morbidities is not fully examined. We aimed to evaluate the safety and efficacy of gastric ESD with co-morbidities categorized according to ASA Physical Status Classification.

METHODS

Two hundred and forty patients of ASA 1 (no co-morbidities), 268 of ASA 2 (mild), and 19 of ASA 3 (severe) were treated by ESD for gastric neoplasms. We retrospectively compared clinicopathological features and treatment results of these three groups.

RESULTS

Cases (by percent) treated with anticoagulant/platelet agents were more common in the higher ASA grades (ASA 1, 5.8%; ASA 2, 29.1%; ASA 3, 31.6%; P < 0.0001). There were no significant differences in case numbers treated under guideline criteria, curative resection (ASA 1, 79.6%; ASA 2, 79.9%; ASA 3, 78.9%), or complications related to the ESD procedure (e.g., postoperative bleeding, perforation, thermal injury). By a patient risk prediction model on surgery, i.e., P-POSSUM, morbidity was halved, and no patients died compared to a predicted death rate of 0.5-2%; however, total and complications unrelated to ESD procedure (e.g., aspiration pneumonia, ischemic heat attack) were more common in higher ASA grades (ASA 1, ASA 2, ASA 3: 15.4, 23.9, 26.3%, respectively, P = 0.014; 0.4, 7.1, 0%, respectively, P = 0.00087). Deviation rates from clinical pathway were more frequent and hospital stay (days) longer in higher ASA grades (ASA 1, ASA 2, ASA 3: 11.3, 17.9, 26.3%, respectively, P = 0.014; 8, 8, 9%, respectively, P = 0.0053).

CONCLUSIONS

ESD is an efficient treatment for gastric neoplasms with co-morbidities. However, additional caution is required because co-morbidity is a risk factor for both total complications and complications unrelated to the ESD procedure, and may cause deviations in the clinical course and prolonged hospital stay.

Principles of quality controlled endoscopic submucosal dissection with appropriate dissection level and high quality resected specimen

Endoscopic submucosal dissection (ESD) has enabled en bloc resection of early stage gastrointestinal tumors with negligible risk of lymph node metastasis, regardless of tumor size, location, and shape. However, ESD is a relatively difficult technique compared with conventional endoscopic mucosal resection, requiring a longer procedure time and potentially causing more complications. For safe and reproducible procedure of ESD, the appropriate dissection of the ramified vascular network in the level of middle submucosal layer is required to reach the avascular stratum just above the muscle layer. The horizontal approach to maintain the appropriate depth for dissection beneath the vascular network enables treatment of difficult cases with large vessels and severe fibrosis. The most important aspect of ESD is the precise evaluation of curability. This approach can also secure the quality of the resected specimen with enough depth of the submucosal layer.

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.

1,635 Endoscopic submucosal dissection cases in the esophagus, stomach, and colorectum: complication rates and long-term outcomes

Background

Endoscopic submucosal dissection (ESD) enables en bloc resection of early gastrointestinal neoplasms; however, most ESD articles report small series, with short-term outcomes performed by multiple operators on single organ. We assessed short- and long-term treatment outcomes following ESD for early neoplasms throughout the gastrointestinal tract.

Methods

We performed a longitudinal cohort study in single tertiary care referral center. A total of 1,635 early gastrointestinal neoplasms (stomach 1,136; esophagus 138; colorectum 361) were treated by ESD by single operator. Outcomes were complication rates, en bloc R0 resection rates, and long-term overall and disease-specific survival rates at 3 and 5 years for both guideline and expanded criteria for ESD.

Results

En bloc R0 resection rates were: stomach: 97.1 %; esophagus: 95.7 %; colorectum: 98.3 %. Postoperative bleeding and perforation rates respectively were: stomach: 3.6 and 1.8 %; esophagus: 0 and 0 %; colorectum: 1.7 and 1.9 %. Intra criteria resection rates were: stomach: 84.9 %; esophagus: 81.2 %; colorectum: 88.6 %. Three-year survival rates for lesions meeting Japanese ESD guideline/expanded criteria were for all organ-combined: 93.4/92.7 %. Five-year rates were: stomach: 88.1/84.6 %; esophagus: 81.6/57.3 %; colorectum: 94.3/100 %. Median follow-up period was 53.4 (range, 0.07–98.6) months. Follow-up rate was 94 % (1,020/1,085). There was no recurrence or disease-related death.

Conclusions

In this large series by single operator, ESD was associated with high curative resection rates and low complication rates across the gastrointestinal tract. Disease-specific and overall long-term prognosis for patients with lesions within intra criteria after curative resection appeared to be excellent.

Does immunohistochemical staining have a clinical impact in early gastric cancer conducted endoscopic submucosal dissection?

AIM: To evaluate clinicopathologic parameters and the clinical significance related lymphovascular invasion (LVI) by immunohistochemical staining (IHCS) in endoscopic submucosal dissection (ESD).

METHODS: Between May 2005 and May 2010, a total of 348 lesions from 321 patients (mean age 63 ± 10 years, men 74.6%) with early gastric cancer (EGC) who met indication criteria after ESD were analyzed retrospectively. The 348 lesions were divided into the absolute (n = 100, differentiated mucosal cancer without ulcer ≤ 20 mm) and expanded (n = 248) indication groups after ESD. The 248 lesions were divided into four subgroups according to the expanded ESD indication. The presence of LVI was determined by factor VIII-related antigen and D2-40 assessment. We compared LVI IHCS-negative group with LVI IHCS-positive in each group.

RESULTS: LVI by hematoxylin-eosin staining (HES) and IHCS were all negative in the absolute group, while was observed in only the expanded groups. The positive rate of LVI by IHCS was higher than that of LVI by HES (n = 1, 0.4% vs n = 11, 4.4%, P = 0.044). LVI IHCS-positivity was observed when the cancer invaded to the mucosa 3 (M3) or submucosa 1 (SM1) levels, with a predominance of 63.6% in the subgroup that included only SM1 cancer (P < 0.01). In a univariate analysis, M3 or SM1 invasion by the tumor was significantly associated with a higher rate of LVI by IHCS, but no factor was significant in a multivariate analysis. There were no cases of tumor recurrence or metastasis during the median 26 mo follow-up.

CONCLUSION: EGCs of the absolute group are immunohistochemically stable. The presence of LVI may be carefully examined by IHCS in an ESD expanded indication group with an invasion depth of M3 or greater.

[Endoscopic submucosal dissection in our practice -- new possibilities in the endoscopic treatment of neoplastic changes in the alimentary canal]

Endoscopic submucosal dissection is a promising new endoscopic technique for en block resection of early, superficial, flat, and laterally spreading gastrointestinal neoplasms. The primary aims of this prospective study were to summarize the first Hungarian experience with endoscopic submucosal dissection, and to compare the experimental in vivo procedures in pigs with the human application of this technique in two academic centers.

METHODS

The ex vivo Erlangen pig model was used until initial competence was achieved. Thereafter 15 endoscopic submucosal dissection procedures were performed in up to 5 sessions in living pigs under general anesthesia. After submucosal injection with saline Fujinone ball tip, a Flush knife was used with a transparent hood for circumferential incision and submucosal dissection. The following variables were analyzed: specimen size, complete and en bloc resection rate, total duration of the procedure, and complications. Furthermore, between 2009 and 2012, 14 endoscopic submucosal dissections were carried out in humans; 1 duodenal, 3 gastric and 10 colorectal interventions were performed due to large laterally spreading intramucosal neoplasms. The specimen size, en bloc resection rate, total duration of the procedure and complications were next analyzed.

RESULTS

87% complete resection rate, 29.4 ± 19.5 cm2 specimen size and 136.2 ± 26.8 min of procedure duration were achieved in the live pig models. Nontransmural damages of the muscular layer occurred in 3/15 (20%) cases which were successfully closed with hemoclips, except in one pig that died due to fatal esophageal perforation. All bleedings were easily managed with hot biopsy forceps coagulation and hemoclips without hemodynamic instability. In humans, endoscopic submucosal dissection was accomplished with an 11/14 (79%) en block resection rate, with average resected specimen size of 11.56 ± 4.9 cm2 and with 157 ± 55 min of operating time. Two cases of bleeding and 2 cases of perforation occurred (14%), all of which were managed endoscopically. After 1.5 year of average follow up, local recurrence occurred in one case only. In addition, due to the 3 incomplete resections and unsuccessful endoscopic submucosal dissection, surgical intervention was required in 4 cases altogether.

CONCLUSIONS

This study demonstrates the first Hungarian experience with endoscopic submucosal dissection. Training in live pig models could help endoscopists to overcome the learning curve and minimize the risk of complications before starting the procedure in humans. Reduction in the resection time and low risk of complications, especially bleeding, could be achieved by the application of a flush knife.

Long-term prognosis of an endoscopically treated rectal neuroendocrine tumor: 10-year experience in a single institution

BACKGROUND AND AIM

The endoscopic techniques for treating a small rectal neuroendocrine tumor (NET) are performed in most large centers; however, the endoscopic management of this condition is not well established. This study was designed to determine the long-term prognosis of endoscopically resected NET.

METHODS

We prospectively studied patients with endoscopically treated rectal NET in Seoul St Mary's hospital, between January 2000 and June 2010. The long-term outcomes were analyzed in association with the pathological complete resection and resection procedures.

RESULTS

Seventy-seven patients (48 men and 29 women; mean age, 52.3 years; range, 23-77 years) were included. The average NET size was 7.0±2.8 mm (range, 3-16 mm). There was no procedure-related complication. En-bloc removal was achieved for all lesions, and the rate of histological complete resection was 75.3% (58/77). Histological complete resection rates were 71.4% (10/14) by conventional endoscopic mucosal resection (EMR), 74.1% (43/58) by a two-channel EMR, and 100.0% (5/5) by endoscopic submucosal dissection (ESD). Among six patients with incomplete histological resection, two underwent additional EMR, two underwent transanal endoscopic microsurgery, and two underwent low anterior section with lymph node dissection. The remaining 13 patients with 'possible' remnant NET underwent regular endoscopic surveillance without additional resection. In the latter group, only one patient had local recurrence, detected on regular colonoscopic surveillance, after 56 months and was treated with additional EMR. All of the patients are alive and 98.7% (76/77) of the patients are free from disease during the follow-up periods.

CONCLUSION

Endoscopic resection is a safe and effective modality and may potentially be used for the treatment of NETs smaller than 15 mm in diameter, those confined to the submucosal layer, and those without metastasis. Local treatment was believed to be curative in cases with complete histological resection. In addition, this treatment may have an excellent prognosis in patients with 'possible' remnant NET.

Successful application of laparoscopic and endoscopic cooperative surgery (LECS) for a lateral-spreading mucosal gastric cancer

In the current era of endoscopic submucosal dissection (ESD) for early gastric cancer, which carries a negligible risk of lymph node metastasis, local resection of the stomach remains an option for these lesions. This is particularly so for a large intramucosal lesion or a lesion with a strong ulcer scar, for which ESD becomes a difficult option. Here, we describe a case of lateral-spreading intramucosal gastric cancer of 6-cm diameter located at the fornix of the stomach, which was successfully treated by laparoscopic and endoscopic cooperative surgery (LECS) because of the expected risk of complications during ESD. In the LECS procedure, the resection margin was appropriately determined by the endoscopic evaluation in detail and by the ESD technique. If early gastric cancer fits the criteria for endoscopic resection but would present difficulty if performing ESD, this is a good indication for the LECS procedure.

A pilot animal and clinical study of autologous blood solution compared with normal saline for use as an endoscopic submucosal cushion

Normal saline is the most popular agent used during endoscopic submucosal injection. However, endoscopists have never identified an optimal submucosal injection solution, which is not only safe and cost-effective but has a unique lifting ability with endoscopic submucosal cushion and causes less tissue damage. This study aimed to evaluate the effectiveness and microscopic characteristics of a blood solution, including whole blood and plasma solution, as a submucosal cushioning agent, compared with normal saline. Endoscopic submucosal dissection (ESD) procedures in pig stomachs were performed by injecting plasma solution (n=4) and normal saline (n=4). A total of 38 patients with gastrointestinal neoplasms underwent endoscopic musocal resection (EMR) procedures. Of 38 EMRs, 7 used whole blood injection, and 31 of 38 acting as the control group used normal saline. A tissue damage scoring system was developed based on injection-induced hydrops and tears for the evaluation of tissue damage. In animal experiments, the lifting time of the injection with normal saline in the pig colon was shorter than that of the group with plasma solution (18.25±5.44 min vs. 6.5±2.38 min, P=0.007). In animal experiments with ESD procedures in the stomach, the hydrops in the normal saline injection group were more extensive than those in the group with plasma (P=0.011). The degree of tearing in the group with normal saline was observed to be less than that in the group with plasma (P=0.008). In patients with EMR, using the histological scoring method, it was determined that the degree of hydrops in the group with normal saline injection was more extensive than that in the group with whole blood (P<0.001). The effective submucosal tearing in the group with normal saline was less than that in the group with blood (P<0.001). The blood solution, including whole blood and plasma solution, as a novel submucosal injection agent, may outperform normal saline with a unique lifting ability, less pronounced tissue damage and marked effective submucosal blunt dissection.

Endoscopic submucosal dissection of early gastric neoplasia with a water jet-assisted knife: a Western, single-center experience

BACKGROUND

Endoscopic submucosal dissection (ESD) of early gastric neoplasia has not yet been established in Western countries because of a lack of data and the difficult, time-consuming, and hazardous nature of the method. Some of the technical limitations may be overcome by use of a water jet-assisted knife, which allows a combination of a high-pressure water jet and electrosurgical interventions.

OBJECTIVE

To evaluate the efficacy and safety of water jet-assisted ESD (WESD) with a water jet-assisted knife in selected patients with early gastric neoplasia.

DESIGN

Single-center, prospective study.

PATIENTS

This study involved 29 consecutive patients (13 female; median age 61 years; age range 35-93 years) with early gastric neoplasia that met the expanded criteria of the Japanese Gastric Cancer Association. Histology of biopsies had shown gastric adenocarcinoma in 21 cases, adenoma in 8 case, and suspicion of a GI stromal tumor in 1 case. The median maximal diameter of the lesions was 20 mm (range 10-40 mm).

INTERVENTION

All procedures were done with patients under sedation with propofol. The water jet-assisted knife was used for setting coagulation markers around the neoplastic lesions, then for circumferential incision and dissection in combination with repeated submucosal injection of saline solution with a water jet system. Bleeding was treated with diathermia by use of the water jet-assisted knife or hemostatic forceps in case of failure or larger vessels. Clips were used for closure of perforations.

MAIN OUTCOME MEASUREMENTS

Complete resection of neoplasia, procedure time, complication and recurrence rates.

RESULTS

According to endoscopic criteria, complete resection of the targeted area could be achieved in all cases, with an en bloc resection rate of 90%. The median procedure duration was 74 minutes (range 15-402 minutes). Exchange of the device was needed in only 10 cases because of severe bleeding from larger vessels, which could be managed by use of hemostatic forceps. The 30-day morbidity rate was 4 of 30 (13.8%) because of postprocedure pain in 3 cases and delayed bleeding in 1 case. A 93-year-old patient died the night after WESD without evidence of a procedure-related complication. Histology of the resected specimens showed adenocarcinoma in 20 cases, adenoma in 7, no neoplasia in 2, and a plasmacytoma in 1. Complete resection (R0) was histologically confirmed in 18 of 28 patients (64.3%) with resected neoplastic specimens. A horizontal or vertical neoplasia-free margin could not be confirmed in 9 cases and 1 case, respectively. Complete local remission of neoplasia was achieved in 25 of 28 patients (89.3%) who were followed over a median period of 22 months (range 6-44 months). In 1 patient, a metachronous gastric adenocarcinoma was identified 54 weeks after initial WESD.

LIMITATIONS

Noncontrolled study with a limited number of patients.

CONCLUSION

The use of a water jet-assisted knife simplifies ESD because exchange of devices is rarely needed. WESD promises to be effective and safe. The study demonstrates that the high rates of en bloc resection of early gastric neoplasia reported in Asia can be reproduced in Western referral centers. However, histology may not always confirm complete resection of horizontal tumor margins. In spite of the unfavorable histology results, the high rate of complete local remission of neoplasia promises that surgical treatment of early gastric neoplasia can be avoided in the majority of cases.

Endoscopic full-thickness resection of submucosal gastric tumors

BACKGROUND AND AIMS

Endoscopic full-thickness resection (EFTR) is a minimally invasive method for en bloc resection of gastrointestinal lesions, such as early cancer or submucosal tumor. The aim of this pilot study was to evaluate a novel EFTR prototype device for full-thickness resection of the gastric wall containing artificial submucosal lesions.

METHODS

Six artificial submucosal tumors were surgically created in the gastric submucosa by implanting 8-mm cork beads in anesthetized pigs. EFTR of the lesions was attempted using a prototype device which consists of a large transparent plastic cap, loaded onto the tip of the endoscope, into which the submucosal lesion and the surrounding gastrointestinal wall can be pulled by using suction, a grasping forceps, or a dedicated anchoring device. An over-the-scope clip (OTSC) can be deployed underneath the submucosal lesion and a pre-loaded snare is used for EFTR above the OTSC.

RESULTS

The median procedure time was 15 min (interquartile range 11-22). Successful resection of the artificial submucosal lesion was achieved in 4/6 (67%) cases. Successful EFTR of the gastric wall was achieved in 3/6 (50%) cases. In all cases, the OTSC closed the EFTR site completely.

CONCLUSIONS

Gastric EFTR using the novel EFTR prototype device is feasible in a live animal model. The technique can achieve a full-thickness gastric wall and submucosal tumor resection with reliable closure of the gastric wall, but further refinements of the technique and device are necessary in order to reliably resect submucosal lesions, especially larger ones.

The Use of Neural Networks in Identifying Risk Factors for Lymph Node Metastasis and Recommending Management of T1b Esophageal Cancer

The objective of this study was to establish a prediction model of lymph node status in T1b esophageal carcinoma and define the best squamous and adenocarcinoma predictors. The literature lacks a satisfactory level of evidence of T1b esophageal cancer management. We performed an analysis pooling the effects of outcomes of 2098 patients enrolled into 37 retrospective studies using “neural networks” as data mining techniques. The percentages for lymph node, lymphatic (L1), and vascular (V1) invasion in Sm1 esophageal cancers were 24, 46, and 20 per cent, respectively. The same parameters apply to Sm2 with 34, 63, and 38 per cent as opposed to Sm3 with 51, 69, and 47 per cent. The respective number of patients with well, moderate, and poor histologic differentiation totaled 267, 752, and 582. The rank order of the predictors of lymph node positivity was, respectively: Grade III, (L1), (V1), Sm3 invasion, Sm2 invasion, and Sm1 invasion. Histologic-type squamous and adenocarcinoma (ADC/SCC) was not included in the model. The best predictors for SCC lymph node positivity were sm3 invasion and (V1). As concerns ADC, the most important predictor was (L1). Submucosal esophageal cancer should be managed with surgical resection. However, this is subject to the histologic type and presence of specific predictors that could well alter the perspective of multimodality management.

Endoscopic submucosal dissection for treatment of gastric subepithelial tumors (with video)

BACKGROUND

Endoscopic submucosal dissection (ESD) is a well-accepted method for removing superficial mucosal tumors; however, there is limited data on the use of this method for removing subepithelial tumors.

OBJECTIVE

To investigate the efficacy, safety, and outcome of ESD for gastric subepithelial tumors and determine factors related to treatment success.

DESIGN

Retrospective analysis of a prospectively maintained database.

SETTING

Single tertiary academic center.

PATIENTS AND INTERVENTIONS

From April 2007 to November 2010, 37 patients with gastric subepithelial tumors were treated with ESD.

MAIN OUTCOME MEASUREMENTS

Macroscopically and microscopically complete en block resection rate (R0), complication rate, and endosonographic features predictive of R0 resection.

RESULTS

The median tumor diameter was 25.0 mm, (range 10-60 mm, IQR 17-37). The overall rate of R0 resections was 81.1% (30/37, 95%CI: 61.8-90.2%), including 100% (15/15, 95%CI: 78.2-100.0%) of tumors from the submucosa and 68.2% (15/22, 95%CI: 45.1-86.1%) of tumors from the muscularis propria. Seventeen patients had a final diagnosis of gastrointestinal stromal tumor. The severe complication (perforation) rate was 5.4% (2/37, 95%CI: 0.0-9.5%). One patient required surgery; the other was treated conservatively. No recurrence was observed in patients with R0 resections at a median follow up of 21.0 months (IQR 11-35). Successful R0 resections were predicted by the observation of no, or only narrow, tumor connections with the underlying muscle layer during EUS (OR=35.0, 95%CI: 3.7-334.4, p=0.001).

LIMITATIONS

Single-center, retrospective analysis, short follow-up.

CONCLUSIONS

ESD is an effective and relatively safe method for removing gastric subepithelial tumors. Endoscopic ultrasonography findings can predict complete tumor resections.

Sodium alginate as an ideal submucosal injection material for endoscopic submucosal resection: preliminary experimental and clinical study

BACKGROUND

Sodium alginate is used clinically in the treatment of peptic ulcer disease. Because of its viscosity, sodium alginate could possibly become a new submucosal injection material for use in endoscopic resection.

OBJECTIVE

We evaluated the feasibility of endoscopic submucosal dissection (ESD) using sodium alginate.

SETTING AND INTERVENTIONS

The lesion-lifting properties of sodium alginate were examined in porcine stomachs and were compared with those of normal saline solution and sodium hyaluronate solution. After confirming the proper concentration of sodium alginate, ESD using sodium alginate was performed in 11 patients with gastric mucosal cancer or adenoma.

MAIN OUTCOME MEASUREMENT

The lesion-lifting properties of sodium alginate and clinical outcomes were assessed.

RESULTS

The thickness of the submucosal elevation created by 3% sodium alginate in porcine stomach was equivalent to that of sodium hyaluronate. ESD using sodium alginate was completed successfully in all patients without adverse effects except in 1 patient in whom transient shrinkage of the gastric wall disappeared spontaneously after approximately 30 minutes. The mean tumor size was 15.3 mm. En bloc resection and a negative resection margin were obtained in all. Histopathologic examination revealed that all tumors were confined to the mucosal layer except for 1 that was confined to the submucosal layer without lymphovascular invasion, and there were no adverse effects such as tissue damage. No patient required additional treatment, and none showed recurrence during a median follow-up period of 28 months.

LIMITATIONS

Small sample size.

CONCLUSION

This preliminary study suggests that sodium alginate might be a novel, safe submucosal injection material for use in endoscopic resection. Further investigation of the properties of sodium alginate is warranted.

Experimental endoscopic submucosal dissection training in a porcine model: learning experience of skilled Western endoscopists

BACKGROUND

Endoscopic submucosal dissection (ESD) demands a new level of endoscopic skill in Europe. A 2-day workshop was set up for trainees to carry out five ESD each in order to obtain the skill level required to perform ESD in the stomach or rectum. This study describes: (i) the workshop setup; (ii) the participant's performance; and (iii) the training effect on post-workshop clinical ESD performance.

METHODS

Eighteen very experienced European endoscopists participated in four half-day (4.5 h) training sessions, with everybody rotating daily through six separate training stations (two each with dual, hook, or hybrid knives) with expert tutors. One anesthetized piglet was used per station and session. After 1 year, the clinical ESD performance was surveyed to estimate the training effect of the workshop.

RESULTS

Overall, 74 ESD were performed, that is, 4.1 ESD per participant. On average ESD lasted 57 min for 6 cm(2) specimens. We detected a 22% rate of perforation (16 of 74 ESD with perforations), mostly attributable to participants with less experience in ESD. Those who started clinical ESD within 1 year after the workshop performed 144 clinical ESD (median 8 [0-20] per trainee) mostly in the stomach (40%) and large bowel (46%) with an acceptable rate of perforation (9.7%) and surgical repair (3.5%) without mortality or persistent morbidity.

CONCLUSION

Intense skill training for ESD is needed to reduce the risk of perforation, as demonstrated by the results of this workshop. We show that experimental ESD training, however, enables skilled European endoscopists to perform ESD in standard locations with moderate risk of perforation during the clinical learning curve.

The incidence of deep vein thrombosis in Japanese patients undergoing endoscopic submucosal dissection

BACKGROUND

Endoscopic submucosal dissection (ESD) is more invasive than other common endoscopic procedures and may increase the risk for deep vein thrombosis (DVT)/pulmonary embolism. The incidence of DVT/pulmonary embolism after ESD has not been adequately studied.

OBJECTIVE

To evaluate DVT incidence and disease-specific features of D-dimer levels in ESD patients.

DESIGN

Prospective cohort study.

SETTING

Single academic center.

PATIENTS

This study involved 60 patients with superficial gastric neoplasms indicated for ESD.

INTERVENTION

For all patients who underwent ESD, ultrasonography of the lower limbs was performed to detect DVT the day after ESD. D-dimer levels were measured 3 times: before ESD, immediately after ESD, and the day after ESD.

MAIN OUTCOME MEASUREMENTS

DVT incidence after ESD.

RESULTS

The DVT incidence was 10.0% (6/60). At all 3 time points, D-dimer measurements were higher in patients with DVT than in patients without DVT. According to receiver operating characteristic curve analysis, the resulting cut-off value of the D-dimer level the day after ESD was 1.9 μg/mL (sensitivity 83.3%; specificity 79.6%) for ESD patients, with superior association to pre-ESD or immediately after ESD. In univariate analyses, high D-dimer levels the day after ESD and the presence of comorbidities were significantly associated with DVT development.

LIMITATIONS

Single center and small number of patients.

CONCLUSION

ESD procedures have a moderate risk for venous thromboembolism. In patients undergoing ESD, D-dimer levels, especially on the day after ESD, may have specific features associated with DVT development.

Advances in treatment of early gastric cancer by endoscopic submucosal dissection

As a result of the emergence and application of magnifying chromoendoscopy, narrow band imaging, confocal laser endoscopy and the enhancement of the awareness of malignant tumors, more and more people have been diagnosed with gastric cancer at early stages. The postoperative five-year survival rate for early gastric cancer (EGC) can reach as high as 90%. Since the emergence of endoscopic submucosal dissection (ESD), its advantage in the treatment of EGC has become more and more evident due to definite therapeutic effect, less physical trauma, high safety, excellent patient compliance, and low therapeutic cost. This paper focuses on the clinical application of ESD in the management of EGC.

Worldwide experiences of endoscopic submucosal dissection: Not just Eastern acrobatics

The high incidence of gastric cancer has led to the initiation of cancer screening programs. As a result, the number of early gastric cancer cases has increased and consequentially, the cancer mortality rate has decreased. Moreover, the development of minimally invasive endoscopic treatment has been introduced for these early lesions. Endoscopic submucosal dissection (ESD) is now recognized as one of the preferred treatment modalities for premalignant gastrointestinal epithelial lesions and early gastric cancer without lymph node metastasis. We review the results of ESD including experiences in Japan and Korea, as well as western countries.

Risk of lymph node metastasis in submucosal esophageal cancer: a review of surgically resected patients

OBJECTIVES

Endoscopic local procedures are increasingly applied in patients with superficial esophageal cancer as an alternative to radical oncologic resection. The objective of this article is to determine the risk of nodal metastases in submucosal (sm) esophageal cancer, comparing the two predominating histologic tumor types, squamous cell cancer (SCC) and adenocarcinoma (ADC).

METHODS

A query of PubMed, MEDLINE, Embase and Cochrane Library (1980-2009) using predetermined search terms revealed 675 abstracts, of which 485 full-text articles were reviewed. A total of 105 articles met the selection criteria. A review of article references and consultation with experts revealed additional articles for inclusion. Studies that enrolled patients with submucosal esophageal cancer and provided adequate extractable data were included.

RESULTS

The pooled outcomes of 7645 patients with esophageal cancer involving the sm level of infiltration were included in the analysis. Overall, the percentage of lymph node metastasis in submucosal cancer was 37%. Lymph node (N), lymphatic (L) and vascular (V) invasion in sm1 esophageal cancers was 27, 46 and 22%, respectively. Within sm2 lesions, N, L and V invasion were involved in 38, 63 and 38% of patients, respectively. Finally, N, L and V involvement in patients with sm3 lesions was 54, 69 and 47%, respectively. The rates of lymph node metastasis for sm1 and sm2 were higher in SCC compared with ADC, whereas the lymph node metastasis for sm3 was comparable, with >50% involvement in both histologic subtypes. SCC revealed an overall more aggressive behavior compared with ADC (N+: 45 vs 26%; L+: 57 vs 37%; V+: 40 vs 18%).

DISCUSSION

While endoscopic therapy may be adequate in selected patients with 'low-risk' sm1 ADC, submucosal SCC necessitates esophageal resection and systematic lymphadenectomy because of its aggressive nature and tendency for early metastasis.

Treatment of gastric epithelial tumours by endoscopic submucosal dissection using an insulated-tip diathermic knife

BACKGROUND

Endoscopic submucosal dissection (ESD) is a promising technique for the treatment of large, pre- and early malignant gastrointestinal lesions.

OBJECTIVE

To assess the rates of en bloc resection, incidence of complications, procedure times and therapeutic outcomes of ESD using an insulated-tip diathermic knife; and to investigate predictors of these outcomes based on the final pathological features of biopsy specimens.

METHODS

One hundred twenty patients with endoscopically suspected gastric epithelial tumours who were treated with ESD from January 2006 to December 2009 were evaluated.

RESULTS

The mean diameter of the gastric epithelial tumours in the present cohort was 1.88 cm. The mean diameter of the resected specimens was 3.33 cm. The en bloc resection rate was 90% (108 of 120). The median length of the operation was 64.6 min. The bleeding and perforation complication rates were 5.0% (six of 120) and 2.5% (three of 120), respectively. Of 10 gastric tumours initially diagnosed as adenocarcinoma on biopsy, four were found to be low-grade dysplasia and six were found to be high-grade dysplasia after resection and final pathological examination. A total of 112 (93.33%) patients underwent curative treatment, eight patients (6.67%) underwent noncurative treatment with ESD, and two patients (1.67%) experienced local recurrence and subsequently underwent surgery.

CONCLUSIONS

ESD is a promising local curative treatment option for gastric epithelial tumours, but still carries the risks of bleeding and⁄or perforation. Differences in the interpretation of histological results among different pathologists and⁄or between biopsy specimens before ESD and the en bloc tissue specimens after ESD will result in discrepancies.

Endoscopic full-thickness resection without laparoscopic assistance for gastric submucosal tumors originated from the muscularis propria

BACKGROUND

This study was designed to evaluate the clinical efficacy, safety, and feasibility of endoscopic full-thickness resection (EFR) for gastric submucosal tumors (SMTs) originated from the muscularis propria.

METHODS

Twenty-six patients with gastric SMTs originated from the muscularis propria were treated by EFR between July 2007 and January 2009. EFR technique consists of five major procedures: (1) injecting normal saline into the submucosa and precutting the mucosal and submucosal layer around the lesion; (2) a circumferential incision as deep as muscularis propria around the lesion by the endoscopic submucosal dissection (ESD) technique; (3) incision into serosal layer around the lesion with Hook knife; (4) completion of full-thickness incision to the tumor including the serosal layer with Hook, IT, or snare by gastroscopy without laparoscopic assistance; (5) closure of the gastric-wall defect with metallic clips.

RESULTS

EFR was successfully performed in all 26 patients without laparoscopic assistance. The complete resection rate was 100%, and the mean operation time was 105 (range, 60-145) min. The mean resected lesion size was 2.8 (range, 1.2-4.5) cm. Pathological diagnosis of these lesions included gastrointestinal stromal tumors (GISTs) (16/26), leiomyomas (6/26), glomus tumors (3/26), and Schwannoma (1/26). No gastric bleeding, peritonitis sign, or abdominal abscess occurred after EFR. No lesion residual or recurrence was found during the follow-up period (mean, 8 months; range, 6-24 months).

CONCLUSIONS

EFR seems to be an efficacious, safe, and minimally invasive treatment for patients with gastric SMT, which makes it possible to resect deep gastric lesion and provide precise pathological diagnosis of it. With the development of EFR, the indication of endoscopic resection may be expanded.

Carbon dioxide submucosal injection cushion: an innovative technique in endoscopic submucosal dissection

AIM

Endoscopic submucosal dissection (ESD) can successfully resect large lesions en bloc, but it requires a satisfactory submucosal (sm) injection agent for proper safety and efficacy. The aim of the present study was to evaluate the effectiveness of carbon dioxide (CO(2) ) as an ESD sm injection agent.

METHODS

In vitro study using porcine stomachs compared CO(2) with normal saline (NS) and sodium hyaluronic acid (SHA) solution, both of which are currently used to provide long-lasting sm elevation during ESD. Histopathological examination assessed differences between CO(2) and NS sm cushions. ESD were then carried out in vivo in the stomach and rectum of a live pig using CO(2) sm injection.

RESULTS

CO(2) sm elevation was significantly longer lasting than either NS or SHA (P<0.001). Histopathology revealed no mucosal layer tissue damage, and dissection of honeycomb-like fibrous connective tissue in the CO(2) sm cushion. Creating and maintaining a CO(2) sm cushion of sufficient elevation combined with partial physical dissection of the sm layer was achieved, followed by complete endoscopic dissection of the sm layer with all ESD, resulting in successful en-bloc resections having a mean specimen size of 24.3mm within 15min.

CONCLUSION

Safety and efficacy of CO(2) as a satisfactory sm injection agent during ESD was successfully demonstrated in these preliminary studies, warranting further investigation of this innovative technique.

Endoscopic submucosal dissection (ESD) using the needle knife: its superiority to ESD using the insulation-tipped diathermic knife in physicians intending to master ESD

In the absence of a supervisor, we conducted endoscopic submucosal dissection (ESD) procedures using the needle-knife and insulation-tipped (IT) diathermic knives for 516 gastric neoplasms in 443 Japanese patients with the diseases. No significant difference was found between IT knife ESD and needle-knife ESD in en bloc resection rates with tumor-free margins (89.8% and 92.9% for IT knife ESD and needle-knife ESD, respectively) and perforation rates (2.2% and 4.6%, respectively). However, the mean procedure time was significantly (P<0.05) shorter in IT knife ESD than in needle-knife ESD (74 and 88 min, respectively) and reached a plateau after accumulating 120 cases of ESD in both procedures. We required a less number of ESD cases before being proficient at needle-knife ESD than in IT knife ESD (30 cases and 60 cases, respectively). Needle-knife ESD is recommended for physicians who intend to master ESD hereafter.

Stricture after endoscopic submucosal dissection for early gastric cancers and adenomas

BACKGROUND AND AIM

 Stricture is a complication that may occur after endoscopic submucosal dissection (ESD) of gastric neoplasms. The goal of the present study was to investigate the incidence, risk factors and management of gastric stricture after ESD.

METHODS

The medical records of 308 patients who underwent ESD for gastric neoplasms were reviewed. Stricture is defined as having symptoms caused by an obstruction through which a 1-cm diameter endoscopic fiber cannot be passed.

RESULTS

Stricture was identified in six of 308 patients (1.9%). Three of the six lesions were located in the prepylorus, two cases in the antrum and one in the cardia. The mean longitudinal distance and the mean area of the resected specimens in the six cases with stricture (7.8 ± 2.0 cm, 34.0 ± 15.8cm(2) , respectively) was significantly larger than in those without stricture (4.5 ± 1.4cm, 12.7 ± 8.3cm(2) , respectively, P<0.01). The ratio of the resected circumference/whole circumference was 83.3±7.5% in those with stricture in comparison to 25.4 ± 16.3% in those without stricture (P<0.01). All six patients underwent endoscopic balloon dilations, and obtained relief from stricture. However, one patient experienced a gastric perforation and recovered following conservative therapy.

CONCLUSION

 Sub-circumferential resection over 75% of the circumference by ESD in the prepylorus, antrum and cardia is a risk factor for the occurrence of stricture. Early intervention might be considered for this high-risk group to avoid a perforation during balloon dilation.

The performance of a novel ball-tipped Flush knife for endoscopic submucosal dissection: a case-control study

BACKGROUND

Endoscopic submucosal dissection (ESD) using short needle knives is safe and effective, but bleeding is a problem due to low haemostatic capability.

AIM

To assess the performance of a novel ball-tipped needle knife (Flush knife-BT) for ESD with particular emphasis on haemostasis.

METHODS

A case-control study to compare the performance for ESD of 30 pairs of consecutive early gastrointestinal lesions (oesophagus: 12, stomach: 32, colorectum: 16) with standard Flush knife (F) vs. Flush knife-BT (BT). Primary outcome was efficacy of intraprocedure haemostasis. Secondary outcomes included procedure time, procedure speed (dividing procedure time into the area of resected specimen), en bloc resection rate and recurrence rate.

RESULTS

Median intraoperative bleeding points and bleeding points requiring haemostatic forceps were smaller in the BT group than in the F group (4 vs. 8, P < 0.0001, 0 vs. 3, P < 0.0001). There was no difference between groups for procedure time; however, procedure speed was shorter in the BT group (P = 0.0078). En bloc and en bloc R0 resection rates were 100%, with no perforation or post-operative bleeding. No recurrence was observed in either group at follow-up 1 year postprocedure.

CONCLUSIONS

Ball-tipped Flush knife (Flush knife-BT) appears to improve haemostatic efficacy and dissection speed compared with standard Flush knife.

Case series of intra-abdominal adhesions induced by artificial ulceration after endoscopic submucosal dissection before additional laparoscopic gastrectomy

BACKGROUND

As endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) increases, increasing numbers of patients require additional gastrectomy with lymph node dissection after noncurative ESD. ESD may cause intra-abdominal adhesions, making additional laparoscopic gastrectomy technically difficult.

OBJECTIVE

To assess the relation of the presence of intra-abdominal adhesions and ESD treatment to allow safe laparoscopic gastrectomy.

DESIGN

Case series from a retrospective review of additional gastrectomy after noncurative ESD.

SETTING

Tertiary care center.

PATIENTS AND INTERVENTIONS

Eight of 333 patients receiving ESD at Oita University Faculty of Medicine from 1999 to 2008 underwent additional laparoscopic gastrectomy because of noncurative ESD.

MAIN OUTCOME MEASUREMENTS

Intra-abdominal adhesions were evaluated by using an adhesion scoring system (0-3 points) and clinicopathologic findings, including artificial ulcerations after ESD.

RESULTS

All patients successfully underwent laparoscopic gastrectomy within 1 to 2 months after ESD. Three patients with large artificial ulceration (>25 mm) after ESD treatment had severe intra-abdominal adhesions (adhesion score > or =2). These patients tended to have a large blood loss and long operation times during laparoscopic gastrectomy. Despite the 2-month interval from ESD to laparoscopic gastrectomy, ulcerations in these patients were at healing stage with inflammatory cells infiltrating the muscular deep layer.

LIMITATION

A retrospective study.

CONCLUSIONS

After ESD with large artificial ulceration (>25 mm), the presence of intra-abdominal adhesions complicating additional laparoscopic gastrectomy was often observed.

Endoscopic submucosal dissection for treatment of rectal carcinoid tumors

BACKGROUND

Conventional EMR has been the endoscopic treatment of choice for rectal carcinoid tumors. However, histologically complete resection often cannot be achieved because the carcinoid tumors are located mainly in the submucosal layer. Endoscopic submucosal dissection (ESD), a new method for large colorectal neoplasm resection, may overcome this problem.

OBJECTIVE

To compare ESD with EMR for the endoscopic treatment of rectal carcinoid tumors.

DESIGN

A prospective case series with comparison to retrospective controls.

SETTING

Tertiary-care center.

PATIENTS

From January 2007 to January 2009 we prospectively enrolled consecutive patients with rectal carcinoid tumors less than 16 mm in diameter and with no regional lymph node enlargement shown by CT or EUS. For comparison, we retrospectively randomly selected patients who had undergone EMR for treatment of rectal carcinoid tumors between March 2000 and December 2006.

INTERVENTION

We performed ESD of rectal carcinoid tumors in prospectively enrolled patients.

MAIN OUTCOME MEASUREMENTS

Rate of en bloc resection, rate of histologically complete resection, incidence of complications, and length of procedures.

RESULTS

The ESD group contained 31 patients (18 male, 13 female; age range 34-65 years), and the EMR group contained 62 patients (42 male, 20 female; age range 22-77 years). Both groups had similar mean rectal carcinoid tumor diameters (ESD 6.8 +/- 2.4 mm, EMR 7.3 +/- 2.2 mm; P = .106). Resection time was longer in the ESD group than in the EMR group (11.4 +/- 3.7 minutes vs 4.2 +/- 3.2 minutes, P < .001). The en bloc resection rate was 100% (31 of 31) in the ESD group and 95.2% (59 of 62) in the EMR group (P = .213). The histologically complete resection rate was 90.3% (28 of 31) in the ESD group and 71.0% (44 of 62) in the EMR group (P = .035). Suspected perforation occurred in 1 ESD patient (3.2%) and in 1 EMR patient (1.6%), and both patients were successfully managed by conservative measures. Immediate bleeding occurred in 1 ESD patient (3.2%) and in 4 EMR patients (6.5%); all instances of bleeding were controlled endoscopically.

LIMITATIONS

Retrospective control study and limited experience at a single center.

CONCLUSION

Compared with EMR, ESD resulted in a higher histologically complete resection rate, had a similar complication rate, and took slightly longer to perform. Given the advantages of complete resection, these findings indicate that ESD may be considered for treatment of rectal carcinoid tumors.

Extensive (8 to 12 cm2) noncircumferential endoscopic mucosal resection for early esophageal cancer

BACKGROUND

Endoscopic mucosal resection (EMR) is an appealing method for treating intramucosal esophageal cancer but must comply with the following stringent requirements: proper preoperative staging, complete resection of the lesion, obtaining a resected specimen for histologic analysis of safety margins, and squamous reepithelialization without stricture formation.

METHODS

A rigid esophagoscope was created to resect up to 12 cm(2) of esophageal mucosa in a single specimen and at a constant depth through the submucosa. Under visual control, the esophageal mucosa is sucked into a transparent window and resected with a thin diathermy wire loop in 10 seconds. After extensive preclinical studies in a sheep model, this article reports our early experience in humans.

RESULTS

Twenty-one hemi-circumferential EMRs were performed for 11 dysplastic Barrett's esophagi and 10 early squamous cell carcinomas with no perforation, one hemorrhage controlled by embolization of the left gastric artery, and one incomplete resection. Deep safety margins were clear in 19 of 21 resected specimens (2 patients, unfit for operations, had submucosal invasion of squamous cell carcinoma and adenocarcinoma, respectively). Lateral margins were not clear by definition in 7 circumferential Barrett's esophagi, but were clear in 4 incomplete Barrett's esophagi and 10 early squamous cell carcinomas.

CONCLUSIONS

Large EMRs of 12 cm(2) can safely be performed at the submucosal level in the esophagus. Although feasible in one session, circumferential EMR in humans is not yet advisable because of the risk of stricture formation during the healing phase. The rate of complications of this series of 21 EMRs in humans is acceptable.

New Endoscopic Techniques: Challenges and Opportunities for Surgical Pathologists

In recent years, significant clinical and technological advances have been made in endoscopic methods for diagnosis and treatment of early gastrointestinal neoplasms. However, essential information related to these novel techniques and their implications for practicing surgical pathologists have largely been missing in the general pathology literature. This article provides a general introduction to these novel therapeutic and diagnostic methods, and discusses their indications, contraindications, and potential limitations. The article aims to enable surgical pathologists to interact more efficiently with basic scientists and clinical colleagues to help implement and improve the existing clinical methods and to advance the new technologies.

Endoscopic treatment of rectal carcinoid tumors

BACKGROUND

Various methods have been reported for the endoscopic treatment of rectal carcinoid tumors. The present study was designed to identify the optimal treatment strategy for an endoscopic resection.

METHODS

Forty rectal carcinoid tumors of 38 patients were treated endoscopically. The indication criteria, complete resection rate, selection of treatment, local recurrence, distant metastases, and complications were analyzed. All tumors were estimated to measure 1 cm or less in diameter, without muscular invasion, atypical features, and lymph node metastases to the pararectal region.

RESULTS

Complete resection of the lesions was obtained in 75.0% (30/40). The complete resection rates were 20.0% (1/5) by conventional polypectomy, 84.6% (22/26) by a two-channel endoscopic mucosal resection, and 77.8% (7/9) by endoscopic submucosal dissection. The 10 cases that did not show a clear submucosal layer after initial endoscopic treatment received additional endoscopic microwave coagulation therapy. There were no local or distant recurrences in the followed-up periods (median, 6.4 years). No difference was observed in the complete resection rate between two-channel endoscopic mucosal resection and endoscopic submucosal dissection.

CONCLUSIONS

Small carcinoid tumors measuring less than 1 cm in diameter can therefore be managed endoscopically with no recurrence or spread. The selection of endoscopic treatment should be made after taking such factors as cost-effectiveness, expertise, and experience into careful consideration.

Endoscopic mucosal resection for staging and therapy of adenocarcinoma of the esophagus, gastric cardia, and upper gastric third

Minamally invasive endoscopic resection techniques allow definitive histological staging for dysplasia and early cancer and in many cases curative treatment. In Barrett's esophagus with High Grade Dysplasia (HGD) or early mucosal cancer, endoscopic mucosal resection (EMR) should be considered both as diagnostic and therapeutic first line procedure, with the possibility to repeat the procedure in case of residual Barrett's dysplasia or mucosal cancer. In early cancer of the the submucosa, surgical resection should be discussed. Endoscopic submucosal dissection (ESD) is a useful therapeutic option for HGD or early cancer in the squamous epithelium of the esophagus or in the stomach when en bloc resection is needed in large lesions.