Endoscopic submucosal dissection: a safe technique for colorectal tumors

Predictors of incomplete resection and perforation associated with endoscopic submucosal dissection for colorectal tumors

BACKGROUND AND OBJECTIVE

Colorectal endoscopic submucosal dissection (ESD) is technically challenging. Our aim was to identify predictors of incomplete resection and perforation in colorectal ESD.

DESIGN

Retrospective study.

SETTING

Academic Japanese endoscopy unit.

PATIENTS AND MAIN OUTCOME MEASUREMENTS

A total of 267 consecutive cases of colorectal tumors treated by ESD from May 2010 to February 2013 were analyzed. Predictors of incomplete resection and perforation, including lesion size, growth type, pathological diagnosis, use of hemostatic forceps, degree of fibrosis, history of biopsy, history of local endoscopic treatment, and endoscopic operability.

RESULTS

The incomplete resection rate was 4.1%. The perforation rate was 5.6%. Univariate analysis identified severe fibrosis (P = .032), submucosal (SM) deep (>1000 μm) invasion (P = .033) and poor endoscopic operability (P = .030) as predictors of incomplete resection, and severe fibrosis (P = .038), postendoscopic treatment (P = .016), and poor endoscopic operability (P = .012) as predictors of perforation. Multivariate analysis identified poor endoscopic operability and SM deep invasion as independent predictors of incomplete resection, and poor endoscopic operability and severe fibrosis as independent predictors of perforation. There was no adjustment of P values for multiple testing.

LIMITATION

A single-center study by a single colonoscopist. All statistical results should be taken as descriptive only.

CONCLUSIONS

Poor endoscopic operability and SM deep invasion were significant independent predictors of incomplete resections. Poor endoscopic operability and severe fibrosis were significant independent predictors of perforation. These features may provide helpful information when planning colorectal ESD.

Endoscopic resection for superficial colorectal neoplasia in Italy: a prospective multicentre study

BACKGROUND

Since there are few prospective studies on colorectal endoscopic resection to date, we aimed to prospectively assess safety and efficacy of endoscopic resection in a cohort of Italian patients.

METHODS

Prospective multicentre assessment of resection of sessile polyps or non-polypoid lesions ≥10mm in size or smaller (if depressed). Outcome measures included complete excision, morbidity, mortality, and residual/recurrence at 12 months.

RESULTS

Overall, 1012 resections in 928 patients were analysed (62.4% sessile polyps, 28.8% laterally spreading tumours, 8.7% depressed non-polypoid lesions). Lesions were prevalent in the proximal colon. En bloc resection was possible in 715/1012 cases (70.7%), whereas piecemeal resection was required in 297 (29.3%). Endoscopically complete excision was achieved in 866 cases (85.6%). Adverse events occurred in 83 (8.2%), and no deaths occurred. Independent predictors of 12-month residual/recurrence were the location of the lesion in the proximal colon (OR 2.22 [95% CI 1.16-4.26]; p=0.015) and piecemeal endoscopic resection (OR 2.76 [95% CI 1.56-4.87]; p=0.0005). Limitations of the study were: potential expertise bias, no data on eligible and potentially resectable excluded lesions, high percentage of lesions<20mm, follow-up limited to 1 year.

CONCLUSION

In this registry study the endoscopic resection of colorectal lesions was safe and achieved high rates of long-term endoscopic clearance.

New technique of en bloc resection of colorectal tumor using laparoscopy and endoscopy cooperatively (laparoscopy and endoscopy cooperative surgery - colorectal)

BACKGROUND AND AIM

Various factors make complete en bloc resection by endoscopic techniques alone of some laterally spreading colorectal tumors difficult or unsafe. Drawing on recent radical developments in endoscopic and laparoscopic techniques for managing colorectal lesions, we aimed to develop a safe resection procedure by using a combination of laparoscopy and endoscopy. We have named this procedure laparoscopic endoscopic cooperative colorectal surgery.

PATIENTS

We have performed this procedure on 3patients who had laterally spreading colorectal tumors. The factors contraindicating endoscopic submucosal dissection were submucosal fibrosis because of previous endoscopic mucosal resection in 1 patient and multiple surrounding diverticula in 2 patients.

TECHNIQUE

The patient is placed under general anesthesia and 5 ports are inserted. Following confirmation of the tumor location by endoscopy and laparoscopy, the colon wall at this site is exposed. First, a mucosa-to-submucosa dissection circumferential to the lesion with an appropriate safety margin is performed endoscopically. Complete full-thickness dissection and excision is then performed by using ultrasonic activating scissors, endoscopy, and laparoscopy cooperatively. The excised lesion is withdrawn intraluminally with endoscopic forceps. The opened colon is then closed with laparoscopic linear staplers.

RESULTS

The mean operating time and blood loss in this series were 205 minutes and 13 mL. There were no intraoperative or postoperative complications. Histological examination revealed tubular adenomas with severe dysplasia and adequate surgical margins in all cases.

CONCLUSION

Laparoscopic endoscopic cooperative colorectal surgery involves removal of a minimal length of colon and is a feasible procedure for en bloc resection of some colonic lateral spreading tumors that would be difficult to resect endoscopically.

Colorectal endoscopic submucosal dissection: Technical advantages compared to endoscopic mucosal resection and minimally invasive surgery

BACKGROUND AND AIM

In recent years, the effectiveness of colorectal endoscopic submucosal dissection (ESD) has been increasingly reported. Herein, we highlight the most recent developments and technical advantages of colorectal ESD compared to EMR and minimally invasive surgery.

METHODS

All candidate lesions for ESD were confirmed as being intramucosal tumors by colonoscopy. Presently, the indications for colorectal ESD approved by the Japanese government's medical insurance system are early colorectal cancers with a maximum tumor size of 2-5 cm; however, many early cancers >5 cm have been treated by ESD in referral centers.

RESULTS

The primary advantage of ESD compared to endoscopic mucosal resection (EMR) is a higher en-bloc resection rate for large colonic tumors that had previously been treated by surgery. ESD has several advantages compared to other therapeutic modalities, such as being a safer technique and providing better quality of life. For rectal cancer treatment, a longer procedure time is required for laparoscopic assisted colectomy, whereas trans-anal resection and trans-anal endoscopic microsurgery are more invasive than ESD with a significantly higher recurrence rate. Accordingly, ESD is the preferred choice for early colorectal cancers when there is no risk of lymph-node metastasis.

CONCLUSION

ESD is an effective procedure for treating non-invasive non-polypoid colorectal tumors. These tumors may be difficult to resect en bloc by conventional EMR. The use of ESD results in a higher en-bloc resection rate and is less invasive than surgery.

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.

Systematic review and meta-analysis of endoscopic submucosal dissection versus transanal endoscopic microsurgery for large noninvasive rectal lesions

BACKGROUND

For almost 30 years, transanal endoscopic microsurgery (TEM) has been the mainstay treatment for large rectal lesions. With the advent of endoscopic submucosal dissection (ESD), flexible endoscopy has aimed at en bloc R0 resection of superficial lesions of the digestive tract. This systematic review and meta-analysis compared the safety and effectiveness of ESD and full-thickness rectal wall excision by TEM in the treatment of large nonpedunculated rectal lesions preoperatively assessed as noninvasive.

METHODS

A systematic review of the literature published between 1984 and 2010 was conducted (Registration no. CRD42012001882). Data were integrated with those from the original databases requested from the study authors when needed. Pooled estimates of the proportions of patients with en bloc R0 resection, complications, recurrence, and need for further treatment in the ESD and TEM series were compared using random-effects single-arm meta-analysis.

RESULTS

This review included 11 ESD and 10 TEM series (2,077 patients). The en bloc resection rate was 87.8 % (95 % confidence interval [CI] 84.3-90.6) for the ESD patients versus 98.7 % (95 % CI 97.4-99.3 %) for the TEM patients (P < 0.001). The R0 resection rate was 74.6 % (95 % CI 70.4-78.4 %) for the ESD patients versus 88.5 % (95 % CI 85.9-90.6 %) for the TEM patients (P < 0.001). The postoperative complications rate was 8.0 % (95 %, CI 5.4-11.8 %) for the ESD patients versus 8.4 % (95 % CI 5.2-13.4 %) for the TEM patients (P = 0.874). The recurrence rate was 2.6 % (95 % CI 1.3-5.2 %) for the ESD patients versus 5.2 % (95 % CI 4.0-6.9 %) for the TEM patients (P < 0.001). Nevertheless, the rate for the overall need of further abdominal treatment, defined as any type of surgery performed through an abdominal access, including both complications and pathology indications, was 8.4 % (95 % CI 4.9-13.9 %) for the ESD patients versus 1.8 % (95 % CI 0.8-3.7 %) for the TEM patients (P < 0.001).

CONCLUSIONS

The ESD procedure appears to be a safe technique, but TEM achieves a higher R0 resection rate when performed in full-thickness fashion, significantly reducing the need for further abdominal treatment.

Systematic review and meta-analysis of endoscopic submucosal dissection versus transanal endoscopic microsurgery for large noninvasive rectal lesions

BACKGROUND

For almost 30 years, transanal endoscopic microsurgery (TEM) has been the mainstay treatment for large rectal lesions. With the advent of endoscopic submucosal dissection (ESD), flexible endoscopy has aimed at en bloc R0 resection of superficial lesions of the digestive tract. This systematic review and meta-analysis compared the safety and effectiveness of ESD and full-thickness rectal wall excision by TEM in the treatment of large nonpedunculated rectal lesions preoperatively assessed as noninvasive.

METHODS

A systematic review of the literature published between 1984 and 2010 was conducted (Registration no. CRD42012001882). Data were integrated with those from the original databases requested from the study authors when needed. Pooled estimates of the proportions of patients with en bloc R0 resection, complications, recurrence, and need for further treatment in the ESD and TEM series were compared using random-effects single-arm meta-analysis.

RESULTS

This review included 11 ESD and 10 TEM series (2,077 patients). The en bloc resection rate was 87.8 % (95 % confidence interval [CI] 84.3-90.6) for the ESD patients versus 98.7 % (95 % CI 97.4-99.3 %) for the TEM patients (P < 0.001). The R0 resection rate was 74.6 % (95 % CI 70.4-78.4 %) for the ESD patients versus 88.5 % (95 % CI 85.9-90.6 %) for the TEM patients (P < 0.001). The postoperative complications rate was 8.0 % (95 %, CI 5.4-11.8 %) for the ESD patients versus 8.4 % (95 % CI 5.2-13.4 %) for the TEM patients (P = 0.874). The recurrence rate was 2.6 % (95 % CI 1.3-5.2 %) for the ESD patients versus 5.2 % (95 % CI 4.0-6.9 %) for the TEM patients (P < 0.001). Nevertheless, the rate for the overall need of further abdominal treatment, defined as any type of surgery performed through an abdominal access, including both complications and pathology indications, was 8.4 % (95 % CI 4.9-13.9 %) for the ESD patients versus 1.8 % (95 % CI 0.8-3.7 %) for the TEM patients (P < 0.001).

CONCLUSIONS

The ESD procedure appears to be a safe technique, but TEM achieves a higher R0 resection rate when performed in full-thickness fashion, significantly reducing the need for further abdominal treatment.

Colonic perforation: can we manage it endoscopically?

Colonic perforation occurs in a variety of clinical scenarios and colonoscopy-associated perforation is one of the important reasons for colonic perforation. Colonoscopy-associated perforation may be diagnosed during colonoscopy procedure by the visualization of evident colonic wall defect or, after the completion of colonoscopy, by the visualization of leaked air in the peritoneal or retroperitoneal space. Recently, the incidence of colonoscopy-associated perforation increased because of the introduction of colorectal endoscopic submucosal dissection. Traditionally, colonoscopy-associated perforation was managed surgically. However, medical management has been introduced widely and endoscopic clipping is the most important component for the medical management of colonoscopy-associated perforation. Timely administration of antibiotics is also important. Large perforations, diagnostic colonoscopy-associated perforations, large amount of pneumoperitoneum, and severe abdominal pain have been reported to be predictive of the necessity of surgery after endoscopic clipping. Surgery should be performed if patients show clinical deterioration even after the initiation of medical management.

Risk factors for vertical incomplete resection in endoscopic submucosal dissection as total excisional biopsy for submucosal invasive colorectal carcinoma

PURPOSE

Endoscopic submucosal dissection (ESD) for colorectal tumor is a minimally invasive treatment. Histologic information obtained from the entire ESD specimen is important for therapy selection in submucosal invasive colorectal carcinoma (SMca). This study aimed to identify risk factors for vertical incomplete resection (vertical margin-positive [VM+]) when ESD was performed as total excisional biopsy for SMca.

METHODS

From June 2003 through December 2011, 78 SMca cases were resected by ESD at Hiroshima University Hospital. Patient and tumor characteristics, intraoperative variables, and histopathology were compared between the VM+ group and the vertical complete resection (vertical margin-negative) group. The ability of magnifying endoscopy (ME) and endoscopic ultrasonography (EUS) to predict VM+ was assessed.

RESULTS

ESD resulted in VM+ in eight cases (10.3 %), with a greater percentage invading to a depth of ≥2,000 vs. <2,000 μm (P = 0.047). Severe submucosal fibrosis was found in five of the eight cases (62.5 %, P = 0.017). Poor differentiation was seen at the deepest invasive portion in six cases (75.0 %), and two of six cases had an invasion depth <2,000 μm. Of 39 EUS cases, 36 not showing deep invasion close to the muscularis propria were completely resected by ESD.

CONCLUSIONS

Submucosal fibrosis and poor differentiation at the deepest invasive portion may be risk factors for VM+ in colorectal ESD for tumors with submucosal deep invasion. ME plus EUS is more likely to help determine whether ESD is indicated as complete total excisional biopsy for SMca.

Successful endoscopic strategies for difficult polypectomy

PURPOSE OF REVIEW

Standard endoscopic polypectomy is a powerful technique to remove most polyps found in the gastrointestinal tract. However, a small percentage of polyps can be classified as difficult, based on size, location, and/or configuration. Traditionally, these difficult polyps were referred for surgical segmental colectomy. Recently, with advancements in endoscopic techniques and accessories, a majority of these difficult polyps are now able to be completely resected using entirely endoscopic techniques.

RECENT FINDINGS

Endoscopic techniques and accessories have been evolving during recent years, including increased dissemination of techniques of endoscopic submucosal dissection to the western hemisphere. In addition to refinement of endoscopic techniques, there has been increased interest in developing improved endoscopic accessories, including novel submucosal injectate with auto-dissecting properties, to improve safety and efficiency of endoscopic resection of difficult polyps.

SUMMARY

This article will review currently available techniques and strategies for successful endoscopic resection for difficult polyps.

Training in endoscopic submucosal dissection

Endoscopic submucosal dissection (ESD) represents an important advancement in the therapy of early neoplastic gastrointestinal lesions by providing higher en-bloc curative resection rate with lower recurrence compared to endoscopic mucosal resection (EMR) and by sparing the involved organ and protecting patient’s quality of life. Despite these advantages ESD is associated with long procedure times and a higher rate of complications, making ESD a challenging procedure which requires advanced endoscopic skills. Thus, there has been a recognized need for structured training system for ESD to enhance trainee experience and, to reduce the risks of complications and inadequate treatment. ESD has a very flat learning curve. However, we do not have uniformly accepted benchmarks for competency. Nevertheless, it appears that, in Japan, more than 30 supervised gastric ESD procedures are required to achieve technical proficiency and minimize complications. A number of training algorithms have been proposed in Japan with the aim to standardize ESD training. These algorithms cannot be directly applied in the West due to substantial differences including the availability of highly qualified mentors, the type of pathology seen, choice of devices, and trainee’s background. We propose a training algorithm for Western physicians which integrates both hands-on training courses, animal model work as well as visits to expert centers. No specific preceptor training programs have been yet developed but there is a consensus that these programs are important for permeation of ESD worldwide.

Training in endoscopic submucosal dissection

Endoscopic submucosal dissection (ESD) represents an important advancement in the therapy of early neoplastic gastrointestinal lesions by providing higher en-bloc curative resection rate with lower recurrence compared to endoscopic mucosal resection (EMR) and by sparing the involved organ and protecting patient's quality of life. Despite these advantages ESD is associated with long procedure times and a higher rate of complications, making ESD a challenging procedure which requires advanced endoscopic skills. Thus, there has been a recognized need for structured training system for ESD to enhance trainee experience and, to reduce the risks of complications and inadequate treatment. ESD has a very flat learning curve. However, we do not have uniformly accepted benchmarks for competency. Nevertheless, it appears that, in Japan, more than 30 supervised gastric ESD procedures are required to achieve technical proficiency and minimize complications. A number of training algorithms have been proposed in Japan with the aim to standardize ESD training. These algorithms cannot be directly applied in the West due to substantial differences including the availability of highly qualified mentors, the type of pathology seen, choice of devices, and trainee's background. We propose a training algorithm for Western physicians which integrates both hands-on training courses, animal model work as well as visits to expert centers. No specific preceptor training programs have been yet developed but there is a consensus that these programs are important for permeation of ESD worldwide.

Endoscopy and polyps-diagnostic and therapeutic advances in management

Despite multiple efforts aimed at early detection through screening, colon cancer remains the third leading cause of cancer-related deaths in the United States, with an estimated 51000 deaths during 2013 alone. The goal remains to identify and remove benign neoplastic polyps prior to becoming invasive cancers. Polypoid lesions of the colon vary widely from hyperplastic, hamartomatous and inflammatory to neoplastic adenomatous growths. Although these lesions are all benign, they are common, with up to one-quarter of patients over 60 years old will develop pre-malignant adenomatous polyps. Colonoscopy is the most effective screening tool to detect polyps and colon cancer, although several studies have demonstrated missed polyp rates from 6%-29%, largely due to variations in polyp size. This number can be as high as 40%, even with advanced (> 1 cm) adenomas. Other factors including sub-optimal bowel preparation, experience of the endoscopist, and patient anatomical variations all affect the detection rate. Additional challenges in decision-making exist when dealing with more advanced, and typically larger, polyps that have traditionally required formal resection. In this brief review, we will explore the recent advances in polyp detection and therapeutic options.

Implementation of endoscopic submucosal dissection for early colorectal neoplasms in Sweden

Objectives. Endoscopic submucosal dissection (ESD) is an effective method for en bloc removal of large colorectal tumors in Japan, but this technique is not yet widely established in western countries. The purpose here was to report the experience of implementing colorectal ESD in Sweden. Methods. Twenty-nine patients with primarily nonmalignant and early colorectal neoplasms considered to be too difficult to remove en bloc with EMR underwent ESD. Five cases of invasive cancer underwent ESD due to high comorbidity excluding surgical intervention or as an unexpected finding. Results. The median age of the patients was 74 years. The median tumor size was 26 mm (range 11–89 mm). The median procedure time was 142 min (range 57–291 min). En bloc resection rate was 72% and the R0 resection rate was 69%. Two perforations occurred amounting to a perforation rate of 6.9%. Both patients with perforation could be managed conservatively. One bleeding occurred during ESD but no postoperative bleeding was observed. Conclusion. Our data confirms that ESD is an effective method for en bloc resection of large colorectal adenomas and early cancers. This study demonstrates that implementation of colorectal ESD is feasible in Sweden after proper training, careful patient selection, and standardization of the ESD procedure.

Current status of endoscopic resection strategy for large, early colorectal neoplasia in Japan

BACKGROUND

Conventional endoscopic resection (CER) for early colorectal neoplasia (CRN) is widely accepted as a minimally invasive treatment. Endoscopic submucosal dissection (ESD) was developed in Japan to resect larger lesions, but ESD was not covered by the Japanese national health insurance until April 2012. In addition, treatment strategies vary considerably among medical facilities. To evaluate the current situation in Japan regarding endoscopic treatment of CRNs measuring ≥20 mm, we conducted a prospective multicenter study at 18 medium-volume and high-volume specialized facilities in cooperation with the Japan Society for Cancer of the Colon and Rectum (JSCCR).

METHODS

The JSCCR conducted a multicenter, observational study of all patients treated by CER and ESD of CRNs measuring ≥20 mm.

RESULTS

From October 2007 to December 2010, CERs and ESDs were performed on 1,845 CRNs (CERs 1,029; ESDs 816). Lesions diagnosed as protruded, flat, and depressed totaled 541, 1224, and 48, respectively. En bloc resection rates and mean procedure times for CER/ESD were 56.9%/94.5% (P < 0.01) and 18 ± 23 min/96 ± 69 min, respectively. The average ESD procedure time was 129 ± 83 min in the ≥40-mm group. As lesion size increased, the CER en bloc resection rate decreased significantly (trend P < 0.01), but the ESD en bloc resection rate remained over 93%. Perforation and delayed bleeding rates of CER/ESD were 0.8%/1.6% (P < 0.05) and 2%/2.2% (P = 0.3), respectively.

CONCLUSIONS

The en bloc resection rate for ESD was significantly higher than for CER, although complication rates were fairly low. Despite a longer procedure time, safety of colorectal ESD has improved in various facilities in Japan. However, ESD for lesions measuring ≥40 mm must be performed by experienced endoscopists due to the longer procedure time.

Warning for unprincipled colorectal endoscopic submucosal dissection: accurate diagnosis and reasonable treatment strategy

Piecemeal endoscopic mucosal resection (EMR) is generally indicated for laterally spreading tumors (LST) >2 cm in diameter. However, the segmentation of adenomatous parts does not affect the histopathological diagnosis and completeness of cure. Thus, possible indications for piecemeal EMR are both adenomatous homogenous-type granular-type LST (LST-G) and LST-G as carcinoma in adenoma without segmentalizing the carcinomatous part. Diagnosis of the pit pattern using magnifying endoscopy is essential for determining the correct treatment and setting segmentation borders. In contrast, endoscopic submucosal dissection (ESD) is indicated for lesions requiring endoscopic en bloc excision, as it is difficult to use the snare technique for en bloc excisions such as in non-granular-type LST (LST-NG), especially for the pseudodepressed type, tumors with a type VI pit pattern, shallow invasive submucosal carcinoma, largedepressed tumors and large elevated lesions, which are often malignant (e.g. nodular mixed-type LST-G). Other lesions, such as intramucosal tumor accompanied by submucosal fibrosis, induced by biopsy or peristalsis of the lesion; sporadic localized tumors that occur due to chronic inflammation, including ulcerative colitis; and local residual early carcinoma after endoscopic treatment, are also indications for ESD. In clinical practice, an efficient endoscopic treatment with segregation of ESD from piecemeal EMR should be carried out after a comprehensive evaluation of the completeness of cure, safety, clinical simplicity, and cost-benefit, based on an accurate preoperative diagnosis.

Indications for and technical aspects of colorectal endoscopic submucosal dissection

Due to the widespread acceptance of gastric and esophageal endoscopic submucosal dissections (ESDs), the number of medical facilities that perform colorectal ESDs has grown and the effectiveness of colorectal ESD has been increasingly reported in recent years. The clinical indications for colorectal ESD at the National Cancer Center Hospital, Tokyo, Japan include laterally spreading tumor (LST) nongranular type lesions >20 mm and LST granular type lesions >30 mm. In addition, 0-IIc lesions >20 mm, intramucosal tumors with nonlifting signs and large sessile lesions, all of which are difficult to resect en bloc by conventional endoscopic mucosal resection (EMR), represent potential candidates for colorectal ESD. Rectal carcinoid tumors less than 1 cm in diameter can be treated simply, safely, and effectively by endoscopic submucosal resection using a ligation device and are therefore not indications for ESD. The en bloc resection rate was 90%, and the curative resection rate was 87% for 806 ESDs. The median procedure time was 60 minutes, and the mean size for resected specimens was 40 mm (range, 15 to 150 mm). Perforations occurred in 23 (2.8%) cases, and postoperative bleeding occurred in 15 (1.9%) cases, but only two perforation cases required emergency surgery (0.25%). ESD was an effective procedure for treating colorectal tumors that are difficult to resect en bloc by conventional EMR. ESD resulted in a higher en bloc resection rate as well as decreased invasiveness in comparison to surgery. Based on the excellent clinical results of colorectal ESDs in Japan, the Japanese healthcare insurance system has approved colorectal ESD for coverage.

Endoscopic resection of large colon polyps

Endoscopic resection, including polypectomy, endoscopic mucosal resection, and endoscopic submucosal dissection, is the preferred treatment method of large colorectal polyps. Its safety and efficacy have been shown. Endoscopic removal techniques are important because they provide a resection specimen for precise histopathologic staging to further direct diagnosis, prognosis, and management decisions. Used according to its indications, it provides curative resection and obviates the higher morbidity, mortality, and cost associated with alternative surgical treatment.

Colorectal lateral spreading tumor subtypes: clinicopathology and outcome of endoscopic submucosal dissection

PURPOSE

This study aims to investigate the clinicopathological features of specific subtypes of laterally spreading tumor (LST) and assessed the outcome of endoscopic submucosal dissection (ESD) based upon subdifferentiation status.

METHODS

A total of 137 LSTs were present in 135 patients; 96 were granular and 41 exhibited a nongranular pattern. Granular LSTs, subdivided into homogeneous and nodular mixed, and nongranular LSTs, subdivided into flat-elevated and pseudodepressed, were retrospectively evaluated with respect to clinicopathological features and results of ESD (en bloc R0 curative resection, procedure time, complication, and recurrence rate) according to specific subtype.

RESULTS

The distribution of high-grade intraepithelial neoplasia and submucosal carcinomas was more prominent among granular nodular mixed tumors than among granular homogeneous tumors (P = 0.007), whereas there was no significant difference between nongranular pseudodepressed tumors and flat-elevated tumors. The frequency of en bloc R0 curative resection did not differ significantly among specific subtypes. For nodular mixed and pseudodepressed lesions, the median tumor size was significantly larger (P < 0.001 for each) and mean procedure time was also longer (P < 0.05 for each) than for the other two subtypes. All complications, which included three perforations, five episodes of postoperative bleeding, and one recurrence, occurred in granular nodular mixed and nongranular pseudodepressed tumors.

CONCLUSION

The risk of cancer varies with the subtypes of LSTs. ESD is an effective treatment for LSTs, however ESD is more technically demanding and carries more complications in pseudodepressed and granular mixed subtypes.

Feasibility of endoscopic submucosal dissection for gastric and colorectal lesions: Initial experience from the Gastrocentro--UNICAMP

OBJECTIVE

Endoscopic submucosal dissection is a technique developed in Japan for en bloc resection with a lower rate of recurrence. It is considered technically difficult and performed only in specialized centers. This study sought to report the initial experience from the Gastrocentro--Campinas State University for the treatment of gastric and colorectal lesions by endoscopic submucosal dissection.

MATERIALS AND METHODS

The guidelines of the Japanese Association of Gastric Cancer were used as evaluative criteria. For colorectal lesions, the recommended standards proposed by Uraoka et al. and Saito et al. were employed. The practicability of the method, the development of complications and histological analysis of the specimens were evaluated.

RESULTS

Sixteen patients underwent endoscopic submucosal dissection from June 2010 to April 2011; nine patients were treated for gastric lesions, and seven were treated for colorectal lesions. The average diameter of the gastric lesions was 28.6 mm, and the duration of resection was 103 min without complications. All lesions presented lesion-free margins. Of the seven colorectal tumors, four were located in the rectum and three were located in the colon. The average size was 26 mm, and the average procedure time was 163 min. Two complications occurred during the rectal resection procedures: perforation, which was treated with an endoscopic clip, and controlled bleeding. One of the lesions presented a compromised lateral margin without relapse after 90 days. Depth margins were all free of lesions.

CONCLUSION

Endoscopic submucosal dissection at our institution achieved high success rates, with few complications in preliminary procedures. The procedure also made appropriate lesion staging possible.

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.

Consensus of the present and prospects on endoscopic diagnosis and treatment in East asian countries

Background and Aim. New diagnostic or therapeutic methods in endoscopy have been used. Current clinical application of these procedures is not well known. The aim of this study is to investigate the present situation on endoscopic diagnosis and treatment of gastrointestinal disorders in East Asian countries. Method. A representative member from the International Gastrointestinal Consensus Symposium Committee provided a questionnaire to physicians in China, Indonesia, Japan, Korea, the Philippines, and Thailand. Results. In total, 514 physicians including gastroenterologists, surgeons, and general practitioners enrolled. The most frequently occurring disorder as the origin of upper gastrointestinal bleeding is gastric ulcer. Capsule endoscopy is selected as the first choice for the diagnosis of small intestine bleeding. The second choice was double-balloon endoscopy or angiography. For patients with gastric adenoma, the number of physicians who choose endoscopic mucosal resection is larger than those selecting endoscopic submucosal dissection (ESD) in China, Indonesia, the Philippines, and Thailand. ESD is chosen first in Japan and Korea. Conclusion. New instruments or techniques on endoscopy have not come into wide use yet, and there is diversity in the situation on it in Asian countries. We should unify the endoscopic diagnostic criteria or treated strategy in patients with GI disease.

Laterally spreading tumors in the colon and rectum

The large and relatively flat colorectal neoplastic lesions called laterally spreading tumors are classified as nonpolypoid despite some mixed patterns with protruding nodules. Large hyperplastic polyps and sessile serrated lesions are non-neoplastic lesions that also have this morphology and may potentially progress to neoplasia. All these large and relatively flat lesions are more frequent in the proximal colon and less conspicuous than polypoid lesions. Their underdiagnosis is a major factor in the failure of colonoscopy to prevent cancer in the proximal colon. The treatment of laterally spreading tumors by endoscopic resection (endoscopic mucosal resection, piecemeal endoscopic mucosal resection, endoscopic submucosal dissection), or by surgery is based on a careful morphologic analysis, taking into account the size and surface with nodules or depression. The technique of endoscopic submucosal dissection should be diffused because it reduces the number of surgical indications.

Clinical outcomes for patients with perforations during endoscopic submucosal dissection of laterally spreading tumors of the colorectum

BACKGROUND

Endoscopic submucosal dissection (ESD) for colorectal neoplasms is not widely performed because of the high risk of perforation. Perforations are divided into macroperforations and microperforations. Currently, there is a limited amount of clinical data on the outcome of patients with these types of perforations during colonic ESD. The aim of this study was to investigate the clinical outcome of patients who sustained colon perforations during ESD. We also compared the clinical outcome of patients with microperforations and those with macroperforations.

METHODS

This study enrolled 101 patients with colorectal laterally spreading tumors (LST) who underwent ESD. We retrospectively reviewed their medical records, including patient demographic data and the clinical, endoscopic, and pathologic features. In the cases where perforation had occurred, the course of hospital treatment was analyzed. All ESD-related perforations were divided into macroperforations and microperforations. A macroperforation was defined as a gross perforation that occurred during an ESD procedure and a microperforation was defined by free air visible on X-rays after the procedure.

RESULTS

Of the 101 enrolled patients, 9 (8.9 %) developed perforations. The most common tumor morphology was nongranular-type LST (5 of 9 cases, 55.6 %) based on endoscopic examination. Five patients had microperforations and four had macroperforations. All macroperforations were closed primarily by endoclips during ESD. The endoscopic characteristics did not differ between the groups. However, the length of hospital stay and the mean duration of NPO and antibiotic treatments were longer for microperforation patients. All patients had conservative nonsurgical management such as fasting, intravenous antibiotics, and nasogastric tube drainage.

CONCLUSIONS

The clinical complications for microperforation patients were worse than those for macroperforation patients. However, the clinical prognoses of patients with perforations that occur during colonic ESD are favorable.

Risk factors for incomplete resection and complications in endoscopic mucosal resection for lateral spreading tumors

AIM

Lateral spreading tumors (LST) are relatively large flat lesions with diameters exceeding 10 mm in length. Endoscopic mucosal resection (EMR) is a commonly used technique for removing LST. We aimed to evaluate the risk factors for incomplete resection and complications of EMR for LST.

METHOD

Between January 2004 and December 2010, 497 patients who underwent EMR for LST were retrospectively reviewed. Risk factors for endoscopic and histopathological complete resection, complications, and clinical outcomes were investigated.

RESULTS

Risks for incomplete resection by piecemeal resection and en bloc resection of a lesion ≥ 30 mm were higher than for en bloc resection of a lesion <30 mm (OR=2.688, CI 1.036-6.993; OR=4.982, CI 1.894-13.101). Risks of post-EMR bleeding for piecemeal resection and en bloc resection for a lesion ≥ 40 mm were higher than for en bloc resection of a lesion <40 mm (OR=15.231, CI 1.816-127.744; OR=43.043, CI 4.306-430.314).

CONCLUSION

We found risk factors of EMR for LST and tentatively suggest a protocol for EMR adapted to the size of LST and resection methods. (i) Following piecemeal resection and en bloc resection for LST ≥ 40 mm, hospitalize patients for 36 h and note risk for incomplete resection and delayed bleeding. (ii) After en bloc resection for 40 mm>LST ≥ 30 mm, hospitalize patients for 12 h and note risk for incomplete resection. (iii) Following en bloc resection for LST<30 mm, hospitalize the patient for 12 h and expect complete resection.

Novel technique of endoscopic submucosal dissection by using external forceps for early rectal cancer (with videos)

BACKGROUND

Endoscopic submucosal dissection (ESD) is more difficult for rectal cancer than for gastric cancer.

OBJECTIVE

To evaluate the feasibility and safety of an ESD procedure by using external forceps for early rectal cancer.

DESIGN

A case series.

SETTING

A tertiary medical center.

PATIENTS

Thirteen patients with early-stage rectal cancer were enrolled. Twelve of the 13 lesions were granular-type laterally spreading tumors and 1 was a protruding tumor.

INTERVENTIONS

After circumferential incision around the lesion with a dual-knife or a flex-knife, bendable external forceps were introduced with the help of grasping forceps inserted through the accessory channel and anchored at the anal margin of the lesion. After the forceps were bent, they were locked. With gentle anal traction and bending applied with the forceps, the lesion was elevated, the submucosal layer was opened, and the submucosal layer was dissected from the grasped side, facilitating dissection of the submucosal layer under direct vision.

MAIN OUTCOME MEASUREMENTS

Technical success, complication rates.

RESULTS

The mean lesion size was 33.0 mm (range 20-80 mm), and the mean operating time was 60 minutes (range 20-150 minutes). All lesions could be resected en bloc with tumor-free margins. Major bleeding after ESD occurred in only 1 patient (7.7%), who did not require blood transfusion. Perforation did not occur in any patient.

LIMITATIONS

Single-center experience, small number of patients.

CONCLUSION

This ESD procedure using external forceps for early-stage rectal cancers is feasible and safe.

Safety and efficacy of colorectal endoscopic submucosal dissection by the trainee endoscopists

The colorectum is known to be the most difficult organ to perform endoscopic submucosal dissection (ESD), however, the training has not been sufficiently established. In our hospital, the essential condition to start colorectal ESD was to experience at least 30 gastric ESD and to have sufficient knowledge and techniques beforehand. Rectal ESD were initially performed under supervision of ESD experts. According to their technical acquisition, the ESD experts allocated lesions to the trainees from smaller lesions in the distal colon to larger lesions in the proximal colon. We retrospectively investigated the outcomes of 92 and 23 colorectal ESD performed by two trainee endoscopists (A/B) who gained experience on our training scheme. The rates of en bloc/complete resection for A and B were 92.4%/73.9% and 95.7%/65.2%, respectively. The rates of bleeding/perforation, which occurred only with A, were 1.1%/3.3%, respectively. Intraoperative perforation occurred in one case (4.3%) in the later period. In the later period, en bloc resection rate remained high in spite of the difficult lesions. Our training scheme enabled trainees to perform colorectal ESD effectively and safely from the initial period. Step-by-step accumulation of cases such as from the rectum to the colon may be desirable for the introduction of colorectal ESD.

Current status of colorectal endoscopic submucosal dissection in Japan and other Asian countries: progressing towards technical standardization

AIM

The primary purpose of this questionnaire survey study was to determine the current status of colorectal endoscopic submucosal dissection (ESD) in specialized Japanese referral centers before and after introduction of a government-approved advanced medical treatment system; and, secondly, to determine the current status of colorectal ESD in other Asian specialized referral centers.

METHODS

A total of 1321 colorectal ESDs were performed in 11 institutions including two Asian centers outside Japan.

RESULTS

Overall en-bloc resection, curative resection, R0 resection, perforation, delayed bleeding and emergency surgery rates were 95.4%, 89.1%, 87.2%, 2.9%, 2.5% and 0.2%, respectively. Similar clinical results were reported in the two Asian centers.

CONCLUSION

There were no significant differences with regards to clinical results between the two periods although the perforation rate decreased from 3.3% to 2.4%. In addition, colorectal ESD has become increasingly standardized technically at specialized referral centers not only in Japan, but several other Asian referral institutions as well.

Current status and future perspectives of endoscopic submucosal dissection for colorectal tumors

Endoscopic submucosal dissection (ESD) allows for en bloc tumor resection irrespective of the size of the lesion. In Japan, ESD has been established as a standard method for endoscopic ablation of malignant tumors in the upper gastrointestinal tract. Although the use of colorectal ESD has been gradually spreading with the development of numerous devices, ESD has not yet been fully established as a standard therapeutic method for colorectal lesions. Currently, colorectal ESD is performed as an 'advanced medical treatment' without national health insurance coverage. With the recent accumulation of numerous cases, the safety and simplicity of colorectal ESD have improved remarkably. Currently in Japan, a prospective multicenter cohort study organized by the Japan Gastroenterological Endoscopy Society is ongoing to clarify the safety and efficacy of colorectal ESD to obtain remuneration from national health insurance. In this report, we showed the outcome regarding safety and efficacy of colorectal ESD through a review of the published work. Of 2719 cases with colorectal ESD at 13 institutions, the complete en bloc resection and perforation rates were 82.8% (61-98.2%, 2082/2516) and 4.7% (1.4-8.2%, 127/2719), respectively. Additional surgery for perforation was very rare because perforations were tiny enough to be closed endoscopically by clips in most of the cases and treated conservatively. In the near future, colorectal ESD will be a common therapeutic method for early colorectal carcinoma.

Matched case-control study comparing endoscopic submucosal dissection and endoscopic mucosal resection for colorectal tumors

BACKGROUND AND AIM

For large colorectal tumors, the en bloc resection rate achieved by endoscopic mucosal resection (EMR) is insufficient, and this leads to a high rate of local recurrence. As endoscopic submucosal dissection (ESD) has been reported to achieve a higher rate of en bloc resection and a lower rate of local recurrence in the short-term, it is expected to overcome the limitations of EMR. We conducted a matched case-control study between ESD and EMR to clarify the effectiveness of ESD for colorectal tumors.

METHODS

Between April 2005 and February 2009, a total of 28 colorectal tumors in 28 patients were resected by ESD and were followed up by colonoscopy at least once. As a control group, 56 EMR cases from our prospectively completed database were matched. En bloc resection, complication and recurrence rates were compared between the two groups.

RESULTS

The mean sizes of the lesions were 27.1 mm in the ESD group and 25.0 mm in the EMR group. The en bloc resection rate was significantly higher in the ESD group (92.9% vs 37.5% with ESD vs EMR), and the rate of perforation was also significantly higher (10.7% vs 0%). All cases of perforation were managed conservatively. No recurrence was observed in the ESD group, whereas local recurrences were detected in 12 EMR cases (21.4%). Eleven of the 12 recurrences (91.7%) were managed endoscopically, and one required surgical resection.

CONCLUSIONS

Endoscopic submucosal dissection is a promising technique for the treatment of colorectal tumors, giving an excellent outcome in comparison with EMR.

Clinical outcomes of endoscopic submucosal dissection and endoscopic mucosal resection for laterally spreading tumors larger than 20 mm

BACKGROUND AND AIMS

Colorectal laterally spreading tumors (LST) > 20 mm are usually treated by endoscopic submucosal dissection (ESD) or endoscopic mucosal resection (EMR). Endoscopic piecemeal mucosal resection (EPMR) is sometimes required. The aim of our study was to compare the outcomes of ESD and EMR, including EPMR, for such LST.

METHODS

A total of 269 consecutive patients with a colorectal LST > 20 mm were treated endoscopically at our hospital from April 2006 to December 2009. We retrospectively evaluated the complications and local recurrence rates associated with ESD, hybrid ESD (ESD with EMR), EMR, and EPMR.

RESULTS

ESD and EMR were performed successfully for 89 and 178 LST, respectively: 61 by ESD; 28 by hybrid ESD; 70 by EMR; and 108 by EPMR. Between-group differences in perforation rates were not significant. Local recurrence rates in cases with curative resection were as follows: 0% (0/56) in ESD; 0% (0/27) in hybrid ESD; 1.4% (1/69) in EMR; and 12.1% (13/107) in EPMR; that is, significantly higher in EPMR. No metastasis was seen at follow up. The recurrence rate for EPMR yielding ≥ three pieces was significantly high (P < 0.001). All 14 local recurrent lesions were adenomas that were cured endoscopically.

CONCLUSIONS

As for safety, ESD/hybrid ESD is equivalent to EMR/EPMR. ESD/hybrid ESD is a feasible technique for en bloc resection and showed no local recurrence. Although local recurrences associated with EMR/EPMR were seen, which were conducted based on our indication criteria, all local recurrences could obtain complete cure by additional endoscopic treatment.

Impact of endoscopic submucosal dissection for the therapeutic strategy of large colorectal tumors

BACKGROUND AND AIMS

The change of therapeutic strategy for large colorectal tumors after the introduction of endoscopic submucosal dissection (ESD) has not yet been clarified. The aim of this study was to estimate the impact of ESD as an initial treatment strategy.

METHODS

A questionnaire was administered to nine expert panelists in colorectal ESD. The questionnaire used retrospective data from consecutive case series. Forty-seven cases of early colorectal tumors (≥ 20 mm) were included. Endoscopic growth types were 25 laterally-spreading tumors (LST) of granular type (G), 15 LST of non-granular types (NG), and seven protruded types. Pathological diagnoses included 15 adenomas (Ad), 18 intramucosal cancers (M), three submucosally-shallow invasive cancers (< 1000 µm) (SMs), and 11 submucosally-deep invasive cancers (≥ 1000 µm) (SMd). The expert panelists completed questionnaires about recommended initial treatment under suppositions of before and after the introduction of ESD. Over-surgery was defined as surgery for Ad, M, and SMs. Non-curative endoscopic resection (ER) was defined as ER for SMd.

RESULTS

After the introduction of ESD, the reduction in the over-surgery rate was estimated at 10.8% for Ad, M, and SMs, and the increase in the non-curative ER rate was estimated at 27.2% for SMd. By endoscopic growth type, the reduction of over-surgery rates for LST-NG, LST-G, and protruded type was 15.5%, 10.5%, and 2.2%, respectively.

CONCLUSIONS

The endoscopists changed their therapeutic strategy for large colorectal tumors to reduce over-surgery, especially in LST-NG, demonstrating the impact of ESD.

[Endoscopic submucosal dissection: only for expert endoscopists?]

Endoscopic submucosal dissection (ESD) can be applied to early gastrointestinal cancers. This technique was developed to achieve radical curative resection and to reduce unnecessary surgical interventions. ESD was designed in eastern countries and is not widely used in the West. Although ESD represents a major therapeutic advance in endoscopy and is performed with curative intent, the complication rate (hemorrhage, perforation) is higher than reported in other techniques, requiring from endoscopists the acquirement of technical skill and experience through a structured and progressive training program to reduce the morbidity associated with this technique and increase its potential benefits. Although there is substantial published evidence on the applications and results of ESD, there are few publications on training in this technique and a standardized training program is lacking. The current article aims to describe the various proposals for training, as well as the basic principles of the technique, its indications, and the results obtained, since theoretical knowledge that would guide endoscopists during the clinical application of ESD is advisable before training begins. Training in an endoscopic technique has a little value without knowledge of the technique's aims, the situations in which it should be applied, and the results that can be expected.

Therapeutic options for iatrogenic colon perforation: feasibility of endoscopic clip closure and predictors of the need for early surgery

BACKGROUND

The therapeutic methods of iatrogenic colon perforation have not been performed despite the increasing rates of successful management by endoscopic clip closure. This study aimed to analyze the efficacy and complications of endoscopic clip closure and to identify the risk factors associated with the need for early surgery to avoid more invasive surgical interventions and adverse complications after endoscopic clip closure for iatrogenic colon perforation.

METHODS

A retrospective multicenter review of the clinical course experienced by 32 patients with iatrogenic colon perforation who were treated using immediate endoscopic clip closure between January 2005 and December 2009 was performed.

RESULTS

The technical success rate for endoscopic clip closure was 91% (29/32). After endoscopic clip closure, 22 patients (76%) required medical treatment for colon perforation, and seven patients (24%) had surgical treatment. Of the 22 patients who had only endoscopic clip closure, 17 (59%) had a favorable clinical course. Five patients had a long hospital stay with complication including abscess formation (three cases). Four patients underwent early surgery within 24 h, and laparoscopic simple closure was possible. But for three patients with surgery delayed more than 48 h, open laparotomy with colon resection including diversion were required. The risk factors associated with the need for early surgical treatment within 24 h after endoscopic clip closure were a large perforation [odds ratio (OR), 9.25; 95% confidence interval (CI), 1.85-46.20], leukocytosis (OR 6.58; 95% CI 1.86-23.29), fever (OR 5.05; 95% CI 1.05-24.28), severe abdominal pain (OR 4.30; 95% CI 1.17-15.83), and a large amount of peritoneal free air (OR 4.05; 95% CI 1.40-11.71).

CONCLUSION

The endoscopic clip closure procedure can significantly reduce the frequency of surgery among patients with iatrogenic colon perforations. However, the decision for surgery must be made early after endoscopic clip closure to prevent adverse complications for patients with higher risk factors.

Endoscopic treatment of large colorectal tumors: comparison of endoscopic mucosal resection, endoscopic mucosal resection-precutting, and endoscopic submucosal dissection

BACKGROUND

Endoscopic mucosal resection (EMR) is a useful therapeutic technique for colorectal tumors. However, for tumors larger than 20 mm, the chance of piecemeal resection is high. Recently introduced endoscopic submucosal dissection (ESD) enables en bloc resection regardless of the tumor size. This study aimed to compare the effectiveness and outcomes of EMR, EMR-precutting (EMR-P), and ESD in the treatment of colorectal tumors 20 mm in size or larger.

METHODS

This study reviewed 523 nonpedunculated colorectal tumors (499 patients) 20 mm or larger that received endoscopic treatment (EMR in 140 cases, EMR-P in 69 cases, and ESD in 314 cases) from January 2004 to November 2009.

RESULTS

The mean sizes of the tumors were 21.7 ± 3.5 mm (EMR), 23.5 ± 5.6 mm (EMR-P), and 28.9 ± 12.7 mm (ESD). The ratios of adenocarcinomas were 15.7% (EMR), 29% (EMR-P), and 37.9% (ESD). The en bloc resection rates were 42.9% (EMR), 65.2% (EMR-P), and 92.7% (ESD), and the complete resection rates were 32.9% (EMR), 59.4% (EMR-P), and 87.6% (ESD). Perforation occurred in 2.9% of the EMR-P cases and 8% of the ESD cases. The recurrence rates were 25.9% (EMR; median follow-up period, 26 months), 3.2% (EMR-P; median follow-up period, 16 months), and 0.8% (ESD; median follow-up period, 17 months).

CONCLUSION

For the treatment of large, nonpedunculated colorectal tumors, ESD is more effective than either EMR or EMR-P. Although ESD is technically demanding, it has clinical significance by overcoming the limitations of both EMR and EMR-P.

Clinical risk factors for perforation during endoscopic submucosal dissection (ESD) for large-sized, nonpedunculated colorectal tumors

BACKGROUND

The possible risk of colonic perforation during endoscopic submucosal dissection (ESD) for colorectal tumors is a barrier to wide application. This retrospective study was performed to evaluate the risk and the predictive factors for perforation during ESD procedure.

METHODS

Between October 2006 and November 2010, a total of 499 consecutive patients (mean age 60.0 ± 11.3 years) who underwent ESD for large-sized (≥ 20 mm), nonpedunculated colorectal tumor were analyzed. First, incidence rate and clinical course of perforation were evaluated. Second, patient-related variables (age, sex, history of aspirin or antiplatelet agents, and comorbidity), endoscopic variables (tumor size, location, and type), procedure-related variables (experience of procedures, procedure time, and materials of submucosal injection), and pathologic diagnosis were analyzed.

RESULTS

The mean size of the lesions was 28.9 mm. The overall en bloc resection rate was 95.0%. Perforation occurred in 37 out of 499 patients (7.4%). Thirty-four patients could be successfully treated conservatively. The type (laterally spreading tumor) and the location (right-sided colon) of the tumors, less experience of the procedure (<100 cases) in each endoscopist, and submucosal injection without hyaluronic acid were associated with higher frequency of perforation (all P < 0.05). On multivariate analysis, laterally spreading type of tumor [odds ratio (OR) 4.10, 95% confidence interval (CI) 1.17-14.34] and submucosal injection with hyaluronic acid (OR 0.31, 95% CI 0.13-0.72) were independent predictive factors.

CONCLUSIONS

Perforation rate was 7.4%, and most cases could be successfully managed nonsurgically. In case of laterally spreading type of tumor, more caution is needed during submucosal dissection and long-lasting submucosal cushion is important for preventing perforation.

Clinical outcomes and factors related to resectability and curability of EMR for early colorectal cancer

BACKGROUND

EMR has emerged as an alternative therapeutic option for selected cases of early colorectal cancer (ECC). However, the factors associated with resectability and curability of EMR for ECC remain unknown.

OBJECTIVE

To investigate clinical outcomes and factors related to resectability and curability in ECC cases treated with EMR.

DESIGN

Retrospective study.

SETTING

Tertiary-care academic medical center.

PATIENTS

This study involved all patients in whom EMR was performed for ECC at Severance Hospital between March 1997 and August 2007. A total of 236 cases of ECC occurring in 231 patients (66.2% men) were enrolled.

INTERVENTION

EMR. Curative surgical resection and lymph node dissection were used in cases that were incompletely cured by EMR.

MAIN OUTCOME MEASUREMENTS

Resectability, curability, and recurrence.

RESULTS

Complete cure was achieved for 162 lesions (68.6%). Of the remaining 74 cases (31.4%), 69 (29.2%) were incompletely cured, and the other 5 (2.1%) had an undetermined resection status and ultimately required supplementary surgical resection for curative treatment. Location on the right side of the colon, piecemeal resection, and submucosal carcinoma were independently associated with incomplete resection, whereas depressed tumor type was independently related to incomplete cure. Among the ECC cases completely cured by EMR and followed for more than a year (n = 118), local recurrence was observed in one case (0.8%) during the median follow-up period of 39.4 months (range 12.4-123.1 months).

LIMITATIONS

Single-center, retrospective study.

CONCLUSION

Our data show that EMR is feasible and could be an effective option for treatment of ECC if the technique is applied with the appropriate indications.

Endoscopic submucosal dissection with or without snaring for colorectal neoplasms

BACKGROUND

Despite a high en bloc resection rate, its technical difficulty and risk of complications limit the widespread use of colorectal endoscopic submucosal dissection (ESD).

OBJECTIVE

To analyze outcomes after colorectal ESD and ESD with snaring (ESD-S), a simplified modification of ESD.

DESIGN

A retrospective observational study.

SETTING

A single, tertiary-care, referral center.

PATIENTS AND INTERVENTION

ESD was performed on 163 lesions in 162 patients and ESD-S on 74 lesions in 71 patients. All lesions were nonpedunculated colorectal neoplasms of 15 mm or larger.

MAIN OUTCOME MEASUREMENTS

We analyzed procedure-related variables such as en bloc resection rate, procedure time, and complications. Histopathologic results were reviewed. Follow-up data were analyzed.

RESULTS

The en bloc resection rate was higher for ESD than for ESD-S (87% vs 64%, P < .01). The histologically complete resection rate was also higher for ESD. However, both rates for resection of lesions of <20 mm were not different between ESD and ESD-S groups. The rates of perforation and bleeding were similar for both groups. Submucosal cancers were present in 21% and 31% of the ESD and ESD-S groups, respectively. One patient from each group developed a local adenoma recurrence.

LIMITATIONS

Retrospective design.

CONCLUSION

Both ESD and ESD-S were safe and effective for resection of colorectal neoplasms. The higher en bloc resection rate for ESD suggests that it should be the first option for resection of suspected superficial submucosal cancers in the colorectum. ESD-S can be a good alternative to ESD for en bloc resection of colorectal lesions of <20 mm.

Endoscopic submucosal dissection of scar-embedded rectal polyps: a prospective study (Esd in scar-embedded rectal polyps)

BACKGROUND & AIMS

Endoscopic submucosal dissection (ESD) was developed for en bloc resection of superficial neoplasm of the digestive tract. We evaluated feasibility and safety of ESD, as a salvage therapy of large refractory rectal polyps, in a tertiary care setting.

METHODS

We prospectively enrolled in the present study and treated by ESD 11 consecutive patients with rectal polyps (median diameter 3.5 cm; range 2-5 cm), who had previously undergone several attempts of endoscopic resection and not suitable for further standard endoscopic treatment. The ESD was carried out with a standard needle knife. Follow up examinations were scheduled at 3, 6, 12 and 24 months.

RESULTS

We achieved apparently complete resection of polyps in 10/11 patients. In one patient ESD was interrupted and the pathology of the resected fragment showed deep submucosal infiltration; this patient underwent surgery. Deep and lateral margins were shown to be free of neoplasm (radical resection) in six out of 11 patients. However all the 10 patients with apparently complete resection were free of recurrence after a mean follow up of 19.2 months (12-24). A T1 adenocarcinoma was radically resected by ESD, with no recurrence. We recorded 2 cases of subcutaneous emphysema, both treated conservatively.

CONCLUSIONS

Radical resection is difficult to be achieved by ESD in patients with rectal scar-embedded polyps. Nevertheless ESD may be proposed as a definitive treatment of selected patients with refractory polyps, avoiding surgery in the majority of them.

Risk factors for unfavorable outcomes after endoscopic removal of submucosal invasive colorectal tumors

BACKGROUND & AIMS

Oncologic surgery is recommended after endoscopic resection of submucosal invasive T1 colorectal carcinomas if patients are considered to be at high risk for tumor recurrence or metastasis. However, there are sparse data on the outcome of high-risk patients treated only by endoscopy.

METHODS

Data were collected from 474 patients who underwent endoscopic resection for T1 colorectal cancers from 1974-2002 at Neuperlach Hospital in Munich, Germany. Patient files were reviewed, and patients or referring physicians were contacted to assess outcomes during a follow-up period of at least 24 months (n = 390). Histopathology and endoscopy factors associated with an unfavorable outcome (local recurrence of tumors, metastasis, or death from colorectal cancer) were assessed.

RESULTS

Of the 390 patients followed, 141 received oncologic surgery, and 249 did not; overall, 10% had an unfavorable outcome (39/390). Multivariate regression analysis revealed that lymphatic vessel infiltration, poor grading of tumor stage, and incomplete endoscopic resection were risk factors for unfavorable outcomes (odds ratios, 7.8, 3.4, and 2.6, respectively). If these risk factors were applied to patients who did not receive oncologic surgery, negative predictive values for an unfavorable outcome were 94.6% for lymphatic vessel infiltration, 94.2% for poor grading of tumor stage, and 96.5% for incomplete endoscopic resection; positive predictive values were 44.4%, 42.9%, and 19.6%, respectively.

CONCLUSIONS

Tumor infiltration of lymphatic vessels is the greatest risk factor for an unfavorable outcome after endoscopic resection for colorectal carcinoma. However, its positive predictive value is low. The decision to perform surgery after endoscopic resection of T1 colorectal cancers should be made on the basis of specific features of each patient.

Feasibility of endoscopic submucosal dissection: a new technique for en bloc resection of a large superficial tumor in the colon and rectum

Endoscopic submucosal dissection (ESD) is a promising procedure that enables en bloc resection of large superficial tumors in the upper gastrointestinal tract. On the other hand, ESD in the colon and rectum is technically difficult to perform because of its anatomical features. At our institution, 137 consecutive superficial colorectal tumors larger than 20 mm in diameter in 137 patients were treated by ESD between April 2007 and October 2010, and 132 lesions were successfully resected. The average procedure time was 79.2 minutes, and the rate of en bloc resection was 89.1% (122/137). The rate of complete resection, defined as en bloc resection with tumor-free lateral and vertical margins, was 85.4% (117/137). The rate of perforation was 3.6% (5/137). Colorectal ESD achieved a high rate of en bloc resection and complete resection and is applicable in the colorectum.

Feasibility of salvage endoscopic mucosal resection by using a cap for remnant rectal carcinoids after primary EMR

BACKGROUND

Secondary endoscopic treatment for remnant lesions of rectal carcinoid tumors after primary EMR or polypectomy is technically difficult because of fibrosis of residual tissues. EMR by using a cap (EMR-C), a method to resect the submucosal layer by suction by using a transparent cap, may be feasible as a salvage treatment.

OBJECTIVE

To assess the feasibility of salvage EMR-C.

DESIGN

Retrospective analysis.

SETTING

Tertiary academic health care system.

PATIENTS

Thirty-one patients who were referred for salvage treatment of a failed en bloc excision of rectal carcinoid tumors after primary EMR or polypectomy between January 2007 and December 2009.

INTERVENTIONS

Salvage EMR-C for remnant carcinoid tumors in the rectum.

MAIN OUTCOME MEASUREMENTS

Rate of complete resection, complications, length of procedure, and recurrence rate.

RESULTS

The mean age of the patients was 52.0±11.8 years (range 30-78 years). The mean tumor size was 8.9±3.2 mm (range 5.0-13.0 mm). The mean procedure time was 9.1±3.7 minutes, and clear resection margins were pathologically confirmed in all 31 patients. The most common complication of salvage EMR-C was bleeding (7 patients, 22.6%), which was successfully treated by hemoclipping in all cases. The 1-year follow-up colonoscopy and CT results for all patients were negative for recurrence.

LIMITATIONS

Retrospective design and limited cases at a single center.

CONCLUSIONS

EMR-C is a feasible salvage therapeutic option for failed en bloc excision after primary endoscopic treatment of rectal carcinoid tumors.