Endoscopic submucosal dissection (ESD) for colorectal tumors

Endoscopic submucosal dissection versus endoscopic mucosal resection for the treatment of rectal lesions involving the dentate line

BACKGROUND

The ideal treatment of epithelial neoplastic rectal lesions involving the dentate line is a controversial issue. Piecemeal endoscopic mucosal resection (EMR) is the most commonly used resection technique, but it is associated with high recurrence rates. Endoscopic submucosal dissection (ESD) has been shown to be safe and effective for the treatment of rectal lesions, but evidence is lacking concerning its application close to the dentate line. The aim of our study is to compare ESD and EMR for the treatment of epithelial rectal lesions involving the dentate line.

METHODS

We identified all cases of endoscopic resections of rectal lesions involving the dentate line performed in two German high-volume centers between 2010 and 2022. Periinterventional and follow-up data were collected and retrospectively analyzed.

RESULTS

We identified 68 ESDs and 62 EMRs meeting our inclusion criteria. ESD showed a significant advantage in en bloc resection rates (89.7% vs. 9.7%; P = 0.001) and complete resection rates (72.1% vs. 9.7%; P = 0.001). The overall curative resection rate was similar between both groups (ESD: 92.6%, EMR: 83.9%; P = 0.324), whereas in the subgroup of low-risk adenocarcinomas ESD was curative in 100% of the cases vs. 14% in the EMR group (P = 0.002). There was one local recurrence after ESD (1,5%) vs. 16 (25.8%) after EMR (P < 0.0001), and the EMR patients required an average of three further interventions.

CONCLUSION

ESD is superior to EMR for the treatment of epithelial rectal lesions involving the dentate line and should be considered the treatment of choice.

Approaches and considerations in the endoscopic treatment of T1 colorectal cancer

The detection of early colorectal cancer (CRC) is increasing through the implementation of screening programs. This increased detection enhances the likelihood of minimally invasive surgery and significantly lowers the risk of recurrence, thereby improving patient survival and reducing mortality rates. T1 CRC, the earliest stage, is treated endoscopically in cases with a low risk of lymph node metastasis (LNM). The advantages of endoscopic treatment compared with surgery include minimal invasiveness and limited tissue disruption, which reduce morbidity and mortality, preserve bowel function to avoid colectomy, accelerate recovery, and improve cost-effectiveness. However, T1 CRC has a risk of LNM. Thus, selection of the appropriate treatment between endoscopic treatment and surgery, while avoiding overtreatment, is challenging considering the potential for complete resection, LNM, and recurrence risk.

Completion Surgery after Non-Curative Local Resection of Early Rectal Cancer

Background

The expanding indications of local - endoscopic and transanal surgical - resection of early rectal cancer has led to their increased popularity and inclusion in the treatment guidelines. The accuracy of the current diagnostic tools in identifying the low-risk T1 tumors that can be curatively treated with a local resection is low, and thus several patients require additional oncologic surgery with total mesorectal excision (TME). An efficient clinical strategy which avoids overtreatment and obstacle surgical procedures is under debate between different disciplines.

Summary

Completion surgery has comparable outcomes to primary surgery regarding perioperative morbidity and mortality but also recurrence rates and overall survival. However, local scarring in the mesorectum can make mesorectal excision technically challenging, especially after full-thickness resections, and has been associated with increased rates of permanent ostomy and worse quality of the TME specimen. This risk seems to be lower after muscle-sparing procedures like endoscopic submucosal dissection, which seem to show a benefit in comparison to full-thickness resections.

Key Messages

Completion surgery after non-curative local resection of gastrointestinal malignancies is safe and feasible. Full-thickness resection techniques can cause scarring of the mesorectum; therefore, muscle-sparing procedures should be preferred.

Endoscopic Submucosal Dissection of a Giant Rectal Adenoma Manifesting as McKittrick-Wheelock Syndrome

McKittrick-Wheelock syndrome (MKWS) is an uncommon clinical manifestation of large, villous, epithelial lesions of the distal colon and rectum. Excessive secretion of electrolyte-rich mucus from these lesions leads to secretory diarrhea, electrolyte disorders and acute renal failure. Several cases of MKWS have been reported since its initial description in 1954. The definitive treatment for the great majority of MKWS cases has consisted of surgical resection of the affected part of the colorectum, usually in the form of a low anterior resection or an abdominoperineal resection with the formation of an ostomy. Recent developments in endoscopic resection techniques now offer new, minimally invasive treatment alternatives for MKWS patients. We present the first reported case in the Western world of MKWS caused by a rectal adenoma with a size of 19 × 10 cm, treated through endoscopic submucosal dissection. Through the lessons learned by this case, as well as by a thorough review of the literature, we discuss this uncommon syndrome, focusing on treatment alternatives.

Characteristics of positive horizontal margins in patients who underwent colorectal endoscopic submucosal dissection

Objectives

Endoscopic submucosal dissection (ESD) enables en bloc resection of colorectal neoplasms, but occasionally results in positive horizontal margins (HMs). However, the site of the resected specimen that tends to be positive for HM has not been investigated. We aimed to clarify the characteristics associated with HMs in lesions resected en bloc with ESD.

Methods

Patients with colorectal neoplasms who underwent en bloc resection with ESD were included in this study. The patients were divided into negative HMs (HM0) and positive or indeterminate HMs (HM1) groups. The characteristics associated with HM1 resection were investigated. In addition, the local recurrence rate during endoscopic follow-up for >6 months after ESD was observed.

Results

In total, 201 lesions were analyzed in 189 patients (HM0, 189 lesions; HM1, 12 lesions). The HM1 group had a significantly larger median lesion diameter (25 vs. 55 mm; p < 0.001) and more lesions with >50% circumference than did the HM0 group (p < 0.001). Furthermore, the prevalence of severe fibrosis was significantly higher in the HM1 group than in the HM0 group (p < 0.001). Positive horizontal sites of the resected specimens were more frequent at the oral and anal sites than at the lateral sites. No local recurrences were observed in either group.

Conclusions

The characteristics associated with HM1 depended on lesion size, particularly lesions with >50% circumference, and submucosal fibrosis.

Advanced Soft Robotic System for In Situ 3D Bioprinting and Endoscopic Surgery

Three-dimensional (3D) bioprinting technology offers great potential in the treatment of tissue and organ damage. Conventional approaches generally rely on a large form factor desktop bioprinter to create in vitro 3D living constructs before introducing them into the patient's body, which poses several drawbacks such as surface mismatches, structure damage, and high contamination along with tissue injury due to transport and large open-field surgery. In situ bioprinting inside a living body is a potentially transformational solution as the body serves as an excellent bioreactor. This work introduces a multifunctional and flexible in situ 3D bioprinter (F3DB), which features a high degree of freedom soft printing head integrated into a flexible robotic arm to deliver multilayered biomaterials to internal organs/tissues. The device has a master-slave architecture and is operated by a kinematic inversion model and learning-based controllers. The 3D printing capabilities with different patterns, surfaces, and on a colon phantom are also tested with different composite hydrogels and biomaterials. The F3DB capability to perform endoscopic surgery is further demonstrated with fresh porcine tissue. The new system is expected to bridge a gap in the field of in situ bioprinting and support the future development of advanced endoscopic surgical robots.

Development and validation of an artificial intelligence-based system for predicting colorectal cancer invasion depth using multi-modal data

OBJECTIVES

Accurate endoscopic optical prediction of the depth of cancer invasion is critical for guiding an optimal treatment approach of large sessile colorectal polyps but was hindered by insufficient endoscopists expertise and inter-observer variability. We aimed to construct a clinically applicable artificial intelligence (AI) system for the identification of presence of cancer invasion in large sessile colorectal polyps.

METHODS

A deep learning-based colorectal cancer invasion calculation (CCIC) system was constructed. Multi-modal data including clinical information, white light (WL) and image-enhanced endoscopy (IEE) were included for training. The system was trained using 339 lesions and tested on 198 lesions across three hospitals. Man-machine contest, reader study and video validation were further conducted to evaluate the performance of CCIC.

RESULTS

The overall accuracy of CCIC system using image and video validation was 90.4% and 89.7%, respectively. In comparison with 14 endoscopists, the accuracy of CCIC was comparable with expert endoscopists but superior to all the participating senior and junior endoscopists in both image and video validation set. With CCIC augmentation, the average accuracy of junior endoscopists improved significantly from 75.4% to 85.3% (P = 0.002).

CONCLUSIONS

This deep learning-based CCIC system may play an important role in predicting the depth of cancer invasion in colorectal polyps, thus determining treatment strategies for these large sessile colorectal polyps.

AGA White Paper: Challenges and Gaps in Innovation for the Performance of Colonoscopy for Screening and Surveillance of Colorectal Cancer

In 2018, the American Gastroenterological Association's Center for GI Innovation and Technology convened a consensus conference, entitled "Colorectal Cancer Screening and Surveillance: Role of Emerging Technology and Innovation to Improve Outcomes." The conference participants, which included more than 60 experts in colorectal cancer, considered recent improvements in colorectal cancer screening rates and polyp detection, persistent barriers to colonoscopy uptake, and opportunities for performance improvement and innovation. This white paper originates from that conference. It aims to summarize current patient- and physician-centered gaps and challenges in colonoscopy, diagnostic and therapeutic challenges affecting colonoscopy uptake, and the potential use of emerging technologies and quality metrics to improve patient outcomes.

Transanal endoscopic microsurgical submucosal dissection (TEM-ESD) for rectal adenomas: a retrospective cohort study of 145 consecutive cases

PURPOSE

Transanal endoscopic microsurgery (TEM) and endoscopic submucosal dissection (ESD) are currently the two most popular methods for resecting large rectal adenomas en bloc. However, damage to the mesorectum in the case of TEM, plus the technical challenges and long procedure times of flexible ESD, are major disadvantages of these procedures. Transanal endoscopic microsurgical submucosal dissection (TEM-ESD) is a new technique, combining the ergonomic features of TEM with the minimally invasive approach of ESD. The aim of our study was to assess the feasibility and safety of TEM-ESD for resection of large rectal adenomas.

METHODS

We retrospectively analyzed all TEM-ESD procedures performed in Karlsruhe Municipal Hospital between 2012 and 2019, isolated all cases of adenomas, and analyzed the perioperative and follow-up data of the patients.

RESULTS

We identified 145 cases matching our criteria. The median size of the lesions was 4.2 cm, and the median operating time was 45 min. The en bloc resection rate was 100%, and the complete en bloc resection rate was 78.6%. The overall morbidity rate was 6.9%. In a median follow-up period of 24 months, there was a local recurrence in 4.8% of the cases.

CONCLUSIONS

TEM-ESD is a safe and feasible therapeutic option for resecting large rectal adenomas, offering high en bloc resection and low recurrence rates combined with short operating time and low morbidity. TRIAL REGISTRATION NUMBER (CLINICALTRIALS.GOV): NCT04870931.

Transanal Endoscopic Microsurgical Submucosal Dissection for Recurrent Rectal Adenomas

BACKGROUND

The local resection of recurrent rectal adenomas is a technically challenging task associated with increased local recurrence rate. Transanal endoscopic microsurgical submucosal dissection (TEM-ESD) uses traction to better expose the fibrotic submucosal layer, and therefore, is a valuable alternative for the treatment of such lesions. The aim of our study was to assess the feasibility and outcomes of TEM-ESD for the resection of recurrent rectal adenomas.

METHODS

We retrospectively analysed all TEM-ESD procedures performed in the Karlsruhe Municipal Hospital between 2012 and 2021 and isolated all cases of recurrent adenomas. Subsequently, we matched these cases 1:1 to TEM-ESD cases for primary rectal adenomas according to the size, localization, and histological type of the lesions and compared the outcomes between the two groups.

RESULTS

We identified 19 cases matching our criteria. The median diameter of the lesions was 25 mm and the median operating time 39 min. Macroscopic en bloc resection was achieved in 100% of the cases and histological complete en bloc resection in 78.9%. There was 1 case of conservatively treated postoperative bleeding. After a median follow-up period of 36 months, there was one local recurrence. After comparing those findings to the outcomes of TEM-ESD for primary rectal lesions, we found no significant differences on total operating time, complete en bloc resection rates, adverse events, and local recurrence.

CONCLUSION

TEM-ESD is a feasible therapeutic option for the resection of recurrent rectal adenomas, offering short operating times as well as high en bloc resection and low recurrence rates.

Transanal endoscopic microsurgical submucosal dissection: Are there advantages over conventional ESD?

INTRODUCTION

Transanal endoscopic microsurgical submucosal dissection (TEM-ESD) is a technique that has been recently described for the treatment of large rectal adenomas and early rectal cancer. The purpose of our study is to compare TEM-ESD with flexible endoscopic submucosal dissection (ESD) in an experimental, ex vivo porcine model.

MATERIAL AND METHODS

We used TEM-ESD and flexible ESD to resect a total of 100 standardized 4 × 4cm lesions in an ex vivo porcine stomach model, performing 50 resections with each technique. Total procedure time, en bloc resection rate, injuries of the muscularis propria, perforation rate and learning curve were analysed.

RESULTS

TEM-ESD was associated with a significantly shorter total procedure time in comparison to ESD (19 min vs. 33 min, p < .001). The rates of en bloc resection, injury of the muscularis propria layer, and perforation were the same in both groups. The learning curve of TEM-ESD was shallower than that of ESD.

CONCLUSION

TEM-ESD showed an advantage over ESD in terms of procedure time and learning curve, with similar en bloc resection rates and safety profile in our experimental model.

Short Message Service reminders reduce outpatient colonoscopy nonattendance rate: A randomized controlled study

BACKGROUND AND AIM

Nonattendance of outpatient colonoscopy leads to inefficient use of health-care resources. We aimed to study the effectiveness of using Short Message Service (SMS) reminder prior in patients scheduled for outpatient colonoscopy on their nonattendance rate.

METHODS

Patients who scheduled for an outpatient colonoscopy and had access of SMS were recruited from three clinics in Hong Kong. Patients were randomized to SMS group and standard care (SC) group. All patients were given a written appointment slip on the booking date. In addition, patients in the SMS group received an SMS reminder 7-10 days before their colonoscopy appointment. Patients' demographics, attendance, colonoscopy completion, and bowel preparation quality were recorded. Logistic regression was performed to identify predictors of nonattendance.

RESULTS

From November 2013 to October 2019, a total of 2225 eligible patients were recruited. A total of 1079 patients were allocated to the SMS group and 1146 to the SC group. The nonattendance rate of patients in the SMS group was significantly lower than that in the SC group (8.9% vs 11.9%, P = 0.022). There were no significant differences in their baseline characteristics and colonoscopy completion rate and bowel preparation quality. A trend towards a higher rate of adequate bowel preparation was observed in the SMS group when compared with the SC group (69.9% vs 65.8%, P = 0.053). Independent predictors for nonattendance included younger age, underprivilege, and existing diabetes.

CONCLUSIONS

An SMS reminder for outpatient colonoscopy is effective in reducing the nonattendance rate and may potentially improve the bowel preparation quality.

ESD and Pit Pattern Diagnosis: Lessons from a Japanese Endoscopist Working in the United States

Endoscopic submucosal dissection (ESD) was developed in 2000s to overcome the limitations of endoscopic mucosal resection (EMR), especially to accomplish en-bloc resection, and it has been accepted worldwide in the past decades. Many ESD devices and diagnosis modalities are currently available, which include pit pattern and narrow band imaging (NBI) diagnoses to evaluate the depth of the tumor preoperatively with sensitivities of 70 to 90%. Depending on the Japanese colorectal guideline, the intramucosal cancer and shallow invasion of the submucosal layer are the main good indications of ESD; however, the ESD practices between Japan and Western countries still vary, including pathologic definition of cancer, tumor/node/metastasis classification, and handling of ESD specimen. In the United States, despite the large demand for treatment of colorectal neoplasm, pit pattern and magnified NBI diagnoses are not widely accepted yet, and piecemeal EMR is still the major method in most of the institutions. Moreover, the specific guideline of ESD is also not available yet. More new technologies are being developed other than conventional ESD methods in Eastern and Western countries, and ESD is now expected to change in the next generation. It is recommended that not only gastroenterologists but also colorectal surgeons have appropriate knowledge of colorectal lesions and their management to ensure current treatments is applied to patients.

A Prospective Study of Factors Associated with Abdominal Pain in Patients during Unsedated Colonoscopy Using a Magnifying Endoscope

Objective With the advent of endoscopic treatment, the detailed diagnosis of colorectal neoplasms made using magnifying colonoscopy has become increasingly important. However, insertion difficulty causes pain in unsedated colonoscopy. The aim of this prospective observational study was to clarify the factors associated with a patient's pain in unsedated colonoscopy using a magnifying endoscope. Methods Patient pain was assessed using a numerical rating scale (0-10) immediately after the procedure. We defined 5 as mild enough pain that patients would not be reluctant to undergo another colonoscopy. Acceptable pain was defined as 5 or less and severe pain was defined as 8 to 10. Univariate and multivariate linear regression analyses were performed using the pain scale score as a dependent variable. Results A total of consecutive 600 patients undergoing unsedated colonoscopies were evaluated to assess their abdominal pain. The completion rate was 99.5% (597/600). The mean pain scale score was 3.88±2.38. The rate of acceptable pain was 80.5% (483/600). The rate of severe pain was 6.7% (40/600) including the incomplete cases. A comparison of polyp-positive and polyp-negative cases revealed no marked difference in patient pain (3.82±2.24 vs. 3.94±2.49, respectively; p=0.590) or insertion time (6.62±3.98 vs. 6.29±4.21, p=0.090), while more observation time was needed in polyp-positive cases than in polyp-negative ones (16.30±4.95 vs. 13.08±4.69, p<0.01). Univariate and multivariate linear regression analyses revealed that an older age, colectomy, antispasmodic agent use, and a small-diameter endoscope were significant factors associated with less patient pain. In particular, a small-diameter endoscope induces significantly more acceptable pain than a non-small diameter endoscope [85.63% (274/320) vs. 73.93% (207/280), p=0.00003]. Conclusion Unsedated colonoscopy using a magnifying endoscope by an expert may result in acceptable pain levels. The use of an antispasmodic agent, particularly hyoscine N-butyl bromide, and a small-diameter endoscope are recommended for reducing abdominal pain during unsedated colonoscopy.

The relationship between local recurrence and positive lateral margin after en bloc resection of colorectal neoplasm

BACKGROUND

The factors associated with recurrence of colonic neoplasm after endoscopic resection with a positive lateral margin are not well known. Thus, we evaluate the relationship between recurrence and positive lateral margin after endoscopic en bloc resection of colorectal neoplasm.

METHODS

A retrospective review of 9302 patients who underwent colonic endoscopic resection from January 2008 to January 2015. Of these, a total of 76 patients with positive lateral margins with clear evidence of the its location on endoscopic picture after endoscopic en bloc resection of colorectal neoplasm (>10 mm) were included.

RESULTS

Ten of 76 (13.2%) patients experienced recurrence during the follow-up period (mean f/u month, 21.7 ± 15.6). In cases with positive lateral margins, the 3- and 5-year local recurrence rate of colorectal neoplasm was 28.1% and 40.1%, respectively. The histological features of the recurrence group were as follows: one case of adenocarcinoma [from low-grade adenoma (LGA)]; two cases of high-grade adenoma (HGA) (one from HGA and one from LGA); and seven cases of LGA (four from adenocarcinoma, two from LGA, and one from HGA). The mean age of patients, locations of the lesions, and histologic type were not significantly associated with local recurrence. In multivariate Poisson regression analyses, total length of lateral margin involvement ≥8 mm (relative risk 12.51; 95% CI 1.11-140.34, p = .040) was a significant predictor of local recurrence.

CONCLUSIONS

Positive lateral margins ≥8 mm may be a reliable predictor of local recurrence after endoscopic en bloc resection of colorectal neoplasm.

Wide-field endoscopic mucosal resection versus endoscopic submucosal dissection for laterally spreading colorectal lesions: a cost-effectiveness analysis

OBJECTIVE

To compare the cost-effectiveness of endoscopic submucosal dissection (ESD) and wide-field endoscopic mucosal resection (WF-EMR) for removing large sessile and laterally spreading colorectal lesions (LSLs) >20 mm.

DESIGN

An incremental cost-effectiveness analysis using a decision tree model was performed over an 18-month time horizon. The following strategies were compared: WF-EMR, universal ESD (U-ESD) and selective ESD (S-ESD) for lesions highly suspicious for containing submucosal invasive cancer (SMIC), with WF-EMR used for the remainder. Data from a large Western cohort and the literature were used to inform the model. Effectiveness was defined as the number of surgeries avoided per 1000 cases. Incremental costs per surgery avoided are presented. Sensitivity and scenario analyses were performed.

RESULTS

1723 lesions among 1765 patients were analysed. The prevalence of SMIC and low-risk-SMIC was 8.2% and 3.1%, respectively. Endoscopic lesion assessment for SMIC had a sensitivity and specificity of 34.9% and 98.4%, respectively. S-ESD was the least expensive strategy and was also more effective than WF-EMR by preventing 19 additional surgeries per 1000 cases. 43 ESD procedures would be required in an S-ESD strategy. U-ESD would prevent another 13 surgeries compared with S-ESD, at an incremental cost per surgery avoided of US$210 112. U-ESD was only cost-effective among higher risk rectal lesions.

CONCLUSION

S-ESD is the preferred treatment strategy. However, only 43 ESDs are required per 1000 LSLs. U-ESD cannot be justified beyond high-risk rectal lesions. WF-EMR remains an effective and safe treatment option for most LSLs.

TRIAL REGISTRATION NUMBER

NCT02000141.

Using Endoscopic Submucosal Dissection as a Routine Component of the Standard Treatment Strategy for Large and Complex Colorectal Lesions in a Western Tertiary Referral Unit

BACKGROUND

Colorectal endoscopic submucosal dissection results in high rates of en bloc resection, few recurrences, and accurate diagnosis, and it is useful in lesions with significant fibrosis. However, endoscopic submucosal dissection has not been widely adopted by Western endoscopists and the published experience from Western centers is very limited.

OBJECTIVES

This study aims to report the outcomes from a UK tertiary center using colorectal endoscopic submucosal dissection as part of a standard lesion specific treatment approach.

DESIGN

This was a retrospective study.

SETTING

The study was conducted in a tertiary referral unit for interventional endoscopy in the United Kingdom.

PATIENTS

A total of 116 colorectal lesions were resected using endoscopic submucosal dissection or hybrid endoscopic submucosal dissection in 107 patients.

MAIN OUTCOME MEASURES

Outcomes included complications, recurrence, requirement for surgery, en bloc and R0 resection.

RESULTS

One hundred sixteen lesions (mean size 58.8mm) were resected using endoscopic submucosal dissection (n = 58) and hybrid endoscopic submucosal dissection (n = 58). Eighty-two (70.7%) had failed attempts at resection (n = 58) or extensive sampling before referral. Twelve contained invasive adenocarcinoma; endoscopic resection was curative in 6. Only 2 of 6 patients with noncurative endoscopic resection agreed to surgery, and none had lymph node metastases. Six of 7 perforations were successfully treated with endoscopic clips. Where endoscopic submucosal dissection was used alone, en bloc resection was achieved in 93% and R0 resection was achieved in 91%. Two patients experienced recurrence; both were managed with endoscopic resection.

LIMITATIONS

This was a retrospective study. Procedures were planned as endoscopic submucosal dissection, but some may have been converted to hybrid endoscopic submucosal dissection and not recorded.

CONCLUSION

Colorectal endoscopic submucosal dissection can be used in a Western center as part of a standard lesion-specific approach to deliver effective organ-conserving treatment to patients with large challenging lesions. Lesion assessment in Western practice should be improved to reduce the incidence of prior heavy manipulation and to guide appropriate referral. See Video Abstract at http://links.lww.com/DCR/A601.

Transanal Minimally Invasive Anal Canal Polyp Resection

Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are operative endoscopies that have been performed since a long time. Recently, an evolution of laparoscopy called transanal minimally invasive surgery began to be popularized, and it can be adopted in the face of difficult cases for EMR/ESD. In this video, a 36-year-old woman was submitted to transanal minimally invasive surgery resection, after unsuccessful ESD, for a 2-cm polyp located anteriorly in the anal canal, just beyond the pectineal line. Preoperative workup showed a uT1m versus T1sm N0 M0 lesion. The procedure was performed with a new reusable transanal platform and a monocurved coagulating hook and grasping forceps. The operative time was 90 minutes. No perioperative complications were registered, and the patient was discharged on postoperative day 1. The pathologic report showed a villotubular adenoma with high-grade dysplasia and distant-free margins. After 1 year, the patient was going well, without any recurrent disease. Transanal minimally invasive surgery resection is a good alternative to conventional endoscopic therapies, allowing a meticulous dissection under the magnified operative field's exposure, and a mucosal-submucosal flap closure under satisfactory surgeon's ergonomics.

Risk Stratification for Covert Invasive Cancer Among Patients Referred for Colonic Endoscopic Mucosal Resection: A Large Multicenter Cohort

BACKGROUND & AIMS

Among patients with large colorectal sessile polyps or laterally spreading lesions, it is important to identify those at risk for submucosal invasive cancer (SMIC). Lesions with overt endoscopic evidence of SMIC are referred for surgery, although those without these features might still contain SMIC that is not visible on endoscopic inspection (covert SMIC). Lesions with a high covert SMIC risk might be better suited for endoscopic submucosal dissection than for endoscopic mucosal resection (EMR). We analyzed a group of patients with large colon lesions to identify factors associated with SMIC, and examined lesions without overt endoscopic high-risk signs to determine factors associated with covert SMIC.

METHODS

We performed a prospective cohort study of consecutive patients referred for EMR of large sessile or flat colorectal polyps or laterally spreading lesions (≥20 mm) at academic hospitals in Australia from September 2008 through September 2016. We collected data on patient and lesion characteristics, outcomes of procedures, and histology findings. We excluded serrated lesions from the analysis of covert SMIC due to their distinct phenotype and biologic features.

RESULTS

We analyzed 2277 lesions (mean size, 36.9 mm) from 2106 patients (mean age, 67.7 years; 53.2% male). SMIC was evident in 171 lesions (7.6%). Factors associated with SMIC included Kudo pit pattern V, a depressed component (0-IIc), rectosigmoid location, 0-Is or 0-IIa+Is Paris classification, non-granular surface morphology, and increasing size. After exclusion of lesions that were obviously SMIC or serrated, factors associated with covert SMIC were rectosigmoid location (odds ratio, 1.87; P = .01), combined Paris classification, surface morphology (odds ratios, 3.96-22.5), and increasing size (odds ratio, 1.16/10 mm; P = .012).

CONCLUSIONS

In a prospective study of 2106 patients who underwent EMR for large sessile or flat colorectal polyps or laterally spreading lesions, we associated rectosigmoid location, combined Paris classification and surface morphology, and increasing size with increased risk for covert malignancy. Rectosigmoid 0-Is and 0-IIa+Is non-granular lesions have a high risk for malignancy, whereas proximally located 0-Is or 0-IIa granular lesions have a low risk. These findings can be used to inform decisions on which patients should undergo endoscopic submucosal dissection, EMR, or surgery. ClinicalTrials.gov, Number: NCT02000141.

Colorectal endoscopic submucosal dissection: patient selection and special considerations

Endoscopic submucosal dissection (ESD) enables en bloc resection of large complex colorectal superficial neoplastic lesions, resulting in very low rates of local recurrence, high-quality pathologic specimens for accurate histopathologic diagnosis and potentially curative treatment of early adenocarcinoma without resorting to major surgical resection. The safety and efficacy of the technique, which was pioneered in the upper gastrointestinal tract, has been established by the consistently impressive outcomes from expert centers in Japan and some other eastern countries. However, ESD is challenging to perform in the colorectum and there is a significant risk of complications, particularly in the early stages of the learning curve. Early studies from western centers raised concerns about the high complication rates, and the impressive results from Japanese centers were not replicated. As a result, many western endoscopists are skeptical about the role of ESD and few centers have incorporated the technique into their practice. Nevertheless, although the distribution of expertise, referral centers and modes of practice may differ in Japan and western countries, ESD has an important role and can be safely and effectively incorporated into western practice. Key to achieving this is meticulous lesion assessment and selection, appropriate referral to centers with the necessary expertise and experience and application of the appropriate technique individualized to the patient. This review discusses the advantages, risks and benefits of ESD to treat colorectal lesions and the importance of preprocedure lesion assessment and in vivo diagnosis and outlines a pragmatic rationale for appropriate lesion selection as well as the patient, technical and institutional factors that should be considered.

Clinical outcomes after endoscopic submucosal dissection for colorectal neoplasia: a systematic review and meta-analysis

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) is an endoscopic resection technique for lesions suspicious of superficial malignancy. It is performed using an ESD knife on its own (standard technique) or by the sequential use of a knife and a snare (hybrid technique). The experience with these techniques is different in Asian and non-Asian countries. We performed a systematic review and meta-analysis of available evidence on colorectal ESD.

METHODS

Electronic databases were searched up to August 2016 for studies evaluating R0, en bloc resection, and adverse event rates of both techniques for the treatment of colorectal lesions. Proportions were pooled by a random effects model.

RESULTS

Ninety-seven studies (71 performed in Asia) evaluated the standard technique and 12 studies (7 in Asia) the hybrid technique. The R0 resection rate of the standard technique was 82.9%, and it was significantly lower in non-Asian versus Asian countries: 71.3% versus 85.6%. The en bloc resection rate was 91% and was significantly lower in non-Asian versus Asian countries (81.2% vs 93%, respectively). Surgery was needed in 1.1% of the ESD-related adverse events, with a significant difference between non-Asian and Asian countries (3.1% vs 0.8%). The R0 and en bloc resection rates with the hybrid technique were significantly lower than those achieved with the standard technique: 60.6% and 68.4%, respectively, with similar adverse event rates.

CONCLUSIONS

In non-Asian countries the standard ESD technique is still failing to achieve acceptable levels of performance. The hybrid technique showed low R0 resection rates and should not be considered as an adequate alternative to the standard technique.

Long-Term Outcome and Surveillance Colonoscopy after Successful Endoscopic Treatment of Large Sessile Colorectal Polyps

PURPOSE

Although there is a consensus about the need for surveillance colonoscopy after endoscopic resection, the interval remains controversial for large sessile colorectal polyps. The aim of this study was to evaluate the long-term outcome and the adequate surveillance colonoscopy interval required for sessile and flat colorectal polyps larger than 20 mm.

MATERIALS AND METHODS

A total of 204 patients with large sessile and flat polyps who received endoscopic treatment from May 2005 to November 2011 in a tertiary referral center were included.

RESULTS

The mean age was 65.1 years and 62.7% of the patients were male. The mean follow-up duration was 44.2 months and the median tumor size was 25 mm. One hundred and ten patients (53.9%) received a short interval surveillance colonoscopy (median interval of 6.3 months with range of 1-11 months) and 94 patients (46.1%) received a long interval surveillance colonoscopy (median interval of 13.6 months with range of 12-66 months). There were 14 patients (6.9%) who had local recurrence at the surveillance colonoscopy. Using multivariate regression analysis, a polyp size greater than 40 mm was shown to be independent risk factor for local recurrence. However, piecemeal resection and surveillance colonoscopy interval did not significantly influence local recurrence.

CONCLUSION

Endoscopic treatment of large sessile colorectal polyps shows a favorable long-term outcome. Further prospective study is mandatory to define an adequate interval of surveillance colonoscopy.

iTRAQ-Based Proteomics Screen identifies LIPOCALIN-2 (LCN-2) as a potential biomarker for colonic lateral-spreading tumors

The improvement and implementation of a colonoscopy technique has led to increased detection of laterally spreading tumors (LSTs), which are presumed to constitute an aggressive type of colonic neoplasm. Early diagnosis and treatment of LSTs is clinically challenging. To overcome this problem, we employed iTRAQ to identify LST-specific protein biomarkers potentially involved in LST progression. In this study, we identified 2,001 differentially expressed proteins in LSTs using iTRAQ-based proteomics technology. Lipocalin-2 (LCN-2) was the most up-regulated protein. LSTs expression levels of LCN-2 and matrix metallopeptidase-9 (MMP-9) showed positive correlation with worse pathological grading, and up-regulation of these proteins in LSTs was also reflected in serum. Furthermore, LCN-2 protein overexpression was positively correlated with MMP-9 protein up-regulation in the tumor tissue and serum of LST patients (former r_s = 0.631, P = 0.000; latter r_s = 0.815, P = 0.000). Our results suggest that LCN-2 constitutes a potential biomarker for LST disease progression and might be a novel therapeutic target in LSTs.

Early Outcomes of Endoscopic Submucosal Dissection for Colorectal Neoplasms According to Clinical Indications

BACKGROUND

Although endoscopic submucosal dissection has been shown to be safe and effective for colorectal tumors, its clinical outcomes vary.

OBJECTIVE

The aim of this study is to assess the outcomes of endoscopic submucosal dissection according to clinical indications.

DESIGN

This is a prospective, multicenter, single-arm study.

SETTING

The study was conducted at special hospitals for colorectal diseases and cancers.

PATIENTS

The study population included consecutive patients aged 20 to 80 years who underwent colorectal endoscopic submucosal dissection for 1) early colorectal cancer, 2) laterally spreading tumors ≥2 cm in diameter, and 3) submucosal tumors.

INTERVENTIONS

Procedures were performed by experienced colonoscopists.

MAIN OUTCOME MEASURES

The primary end points were en bloc and curative resection rates. En bloc resection was defined as endoscopic one-piece resection without tumor fragmentation. Curative resection was defined as en bloc resection and no pathologic requirement for additional surgery. Secondary end points included procedure time, complications, and hospital stay.

RESULTS

Of 321 patients, 317 (98.8%) underwent en bloc resection and 231 (72.0%) underwent curative resection. The mean procedure time was 46.2 minutes. Mean hospital stay after the procedure was 3.1 days. Perforation occurred in 2 patients (0.6%), and bleeding occurred in 10 (3.1%) patients. All patients with complications were treated by endoscopic clipping or nonoperative management. Fifteen patients (4.7%) underwent additional radical surgery owing to the risks of lymph node metastasis. Although tumor size was smaller and procedure time shorter in the submucosal tumor group than in the laterally spreading tumor or early colorectal cancer group, there were no differences in clinical outcomes including en bloc and curative resection rates. Submucosal fibrosis was the only factor affecting endoscopic submucosal dissection procedure-related complications.

LIMITATIONS

Early outcomes in a limited population and the potential for selection bias were limitations of this study.

CONCLUSIONS

Outcomes of colorectal endoscopic submucosal dissection were acceptable in selected patients, with no difference in outcomes according to clinical indications. Because submucosal fibrosis can increase complications, it should be minimized before endoscopic submucosal dissection.

Colorectal endoscopic submucosal dissection from a Western perspective: Today’s promises and future challenges

Over the last few years, endoscopic submucosal dissection (ESD) has shown to be effective in the management of early colorectal neoplasms, particularly in Asian countries where the technique was born. In the Western world, its implementation has been slow and laborious. In this paper, the indications for ESD, its learning model, the available methods to predict the presence of deep submucosal invasion before the procedure and the published outcomes from Asia and Europe will be reviewed. Since ESD has several limitations in terms of learning achievement in the West, and completion of the procedure for the first cases is difficult in our part of the world, a short review on colorectal assisted ESD has been included. Finally, other endoscopic and surgical treatment modalities that are in competition with colorectal ESD will be summarized.

Endoscopic submucosal dissection vs laparoscopic colorectal resection for early colorectal epithelial neoplasia

AIM: To compare the short term outcome of endoscopic submucosal dissection (ESD) with that of laparoscopic colorectal resection (LC) for the treatment of early colorectal epithelial neoplasms that are not amenable to conventional endoscopic removal.

METHODS: This was a retrospective cohort study. The clinical data of all consecutive patients who underwent ESD for endoscopically assessed benign lesions that were larger than 2 cm in diameter from 2009 to 2013 were collected. These patients were compared with a cohort of controls who underwent LC from 2005 to 2013. Lesions that were proven to be malignant by initial endoscopic biopsies were excluded. Mid and lower rectal lesions were not included because total mesorectal excision, which bears a more complicated postoperative course, is not indicated for lesions without histological proof of malignancy. Both ESD and LC were performed by the same surgical unit with a standardized technique. The patients were managed according to a standard protocol, and they were closely monitored for complications after the procedures. All hospital records were reviewed, and the following data were compared between the ESD and LC groups: patient demographics, size and location of the lesions, procedure time, short-term clinical outcomes and pathology results.

RESULTS: From 2005 to 2013, 65 patients who underwent ESD and 55 patients who underwent LC were included in this study. The two groups were similar in terms of sex (P = 0.41) and American Society of Anesthesiologist class (P = 0.58), although patients in the ESD group were slightly older (68.6 ± 9.4 vs 64.6 ± 9.9, P = 0.03). ESD could be accomplished with a shorter procedure time (113 ± 66 min vs 153 ± 43 min, P < 0.01) for lesions of comparable size (3.0 ± 1.2 cm vs 3.4 ± 1.4 cm, P = 0.22) and location (colon/rectum: 59/6 vs colon/rectum: 52/3, P = 0.43). ESD appeared to be associated with a lower short-term complication rate, but the difference did not reach statistical significance (10.8% vs 23.6%, P = 0.06). In the LC arm, a total of 22 complications occurred in 13 patients. A total of 7 complications occurred in the ESD arm, including 5 perforations and 2 episodes of bleeding. All perforations were observed during the procedure and were successfully managed by endoscopic clipping without emergency surgical intervention. Patients in the ESD arm had a faster recovery than patients in the LC arm, which included shorter time to resume normal diet (2 d vs 4 d, P = 0.01) and a shorter hospital stay (3 d vs 6 d, P < 0.01).

CONCLUSION: ESD showed better short-term clinical outcomes in this study. Further prospective randomized studies will be required to evaluate the efficacy and superiority of colorectal ESD over LC.

Learning curve analysis of colorectal endoscopic submucosal dissection (ESD) for laterally spreading tumors by endoscopists experienced in gastric ESD

BACKGROUND

Endoscopic submucosal dissection (ESD) for various colorectal neoplasms is more technically difficult than gastric ESD. We evaluated treatment outcomes and the learning curve for colorectal ESD of laterally spreading tumors (LSTs) based on the experience of a single endoscopist.

METHODS

We included 93 colorectal ESD procedures for colorectal LST that were performed between March 2009 and June 2012 by a single experienced endoscopist who previously performed hundreds of cases of gastric ESD. The cases were grouped chronologically into three periods by multi-dimensional analyses. For procedure time, the learning curve was analyzed using the moving average method, and for complication, the learning curve was analyzed using cumulative sum (cusum) method.

RESULTS

The median procedure time for 93 colorectal ESD was 45 min, and the rates of en bloc resection and R0 resection were 89.25 and 83.87 %. When results were compared among three periods in order to determine the learning curve, the procedure time and en bloc resection rates were not significantly different. However, the procedure proficiency (about 0.16 cm(2)/min) was significantly faster during the second period, after about 25 cases of colorectal ESD. In the third period (about 50 cases), the number and rate of en bloc resection (over 90 %) reached the same as that of en bloc R0 resection. When comparing outcomes based on LST subtype, the procedure proficiency of LST-granular type (LST-G) was significantly faster than that of LST-non granular type (LST-NG) (LST-NG, 0.072 cm(2)/min; LST-G, 0.157 cm(2)/min; p = 0.01).

CONCLUSION

Endoscopists fully experienced in gastric ESD need a relatively short learning period for colorectal ESD in terms of procedure time and complication. However, approximately 50 cases might be needed to acquire an adequate skill of colorectal ESD for LST in an experienced gastric ESD endoscopist. Colorectal ESD for LST-NG seems to have higher technical difficulty and a longer learning curve than LST-G.

Efficacy and adverse events of EMR and endoscopic submucosal dissection for the treatment of colon neoplasms: a meta-analysis of studies comparing EMR and endoscopic submucosal dissection

BACKGROUND

EMR and endoscopic submucosal dissection (ESD) are used frequently to remove colon neoplasms. However, the predominance of these procedures has not yet been thoroughly explored.

OBJECTIVE

To compare the efficacy and adverse events related to EMR with those related to ESD for colon neoplasms.

DESIGN

A meta-analysis of 8 studies published between 2005 and 2013.

SETTING

Multicenter review.

PATIENTS

Patients from 8 studies yielding 2299 lesions.

INTERVENTIONS

EMR or ESD.

MAIN OUTCOME MEASUREMENTS

En bloc resection, curative resection, recurrence, and adverse events.

RESULTS

The pooled odds ratios (OR) (OR [95% confidence interval]) for the tumor size, length of the procedure, en bloc resection, curative resection, recurrence, additional surgery, delayed bleeding, and perforation by ESD versus EMR were 7.38 (6.42-8.34), 58.07 (36.27-79.88), 6.84 (3.30-14.18), 4.26 (3.77-6.57), 0.08 (0.04-0.17), 2.16 (1.16-4.03), 0.85 (0.45-1.60), and 4.96 (2.79-8.85), respectively.

LIMITATIONS

This analysis included only nonrandomized studies.

CONCLUSION

The size of the tumor and rate of en bloc resection and curative resection were higher, and the rate of recurrence was lower in the ESD group versus the EMR group. However, in the ESD group, the procedure was longer, and the rate of additional surgery and perforation was higher, suggesting that the indications for ESD should therefore be rigorously determined in order to avoid such problems.

Endoscopic submucosal dissection for colorectal neoplasms

Endoscopic submucosal dissection (ESD) is an established therapeutic technique for the treatment of gastrointestinal neoplasms. Because it is typically completed as en bloc resection, this technique provides a complete specimen for precise pathological evaluation. On the other hand, ESD is not as widely applied in treating colorectal neoplasms as with gastric cancers, due to its technical difficulty, longer procedure time, and increased risk of perforation. However, some devices that facilitate ESD and improve the safety of the procedure have been recently reported, and the use of the technique has gradually spread worldwide. Endoscopists who begin to perform ESD need to recognize the indications of ESD, the technical issue involved in this procedure, and its associated complications. This review outlines the methods and certain types of devices used for colorectal ESD.

Endoscopic submucosal dissection in the colorectum: Feasibility in the Canadian setting

Endoscopic submucosal dissection is a minimally invasive endoscopic technique for the removal of gastrointestinal tumours that is increasingly being used for colonic neoplasms to spare resection of colon in selected patients. Colonic endoscopic submucosal dissection is technically challenging and was initially pioneered in Japan but increasingly used in selected western centres. Its use in Canada is currently limited, and the authors review the challenges and opportunities, in addition to the unique training infrastructure required to practice the procedure under supervision. Specific tools are required to perform endoscopic submucosal dissection and meticulous attention to detail is essential. The authors provide a combined Japanese and Canadian perspective to this technique, and discuss training and performance of endoscopic submucosal dissection as well as potential indications.

Review article: the investigation and management of gastric neuroendocrine tumours

BACKGROUND

Gastric carcinoids (GCs) or neuroendocrine tumours (NETs) are increasingly identified at endoscopy, and account for 0.6-2% of all gastric polyps identified. The SEER database in the US has demonstrated a rising incidence of gastric NETs amongst all NETs; from 2.2% between 1950 and 1969 to 6.0% between 2000 and 2007.

AIM

To review the literature and assist clinicians in managing patients with GCs.

METHODS

A literature search was conducted through MEDLINE using search terms: gastric, carcinoid, neuroendocrine tumour, therapy, endoscopy, mucosal resection, submucosal dissection. Relevant articles were identified through manual review. The reference lists of these articles were reviewed to include further appropriate articles.

RESULTS

There are three types of GCs with important epidemiological, pathophysiological, histological and endoscopic differences that affect prognosis and management. Type 1 and 2 GCs develop in the context of hypergastrinaemia that originates from achlorhydria in atrophic gastritis and a gastrinoma, respectively. Type 3 GCs occur sporadically and independent of gastrin. The histological type, grade and Ki67 index are used to determine prognosis and direct clinical management. Type 1 GCs >1 cm in size and type 2 GCs should be assessed for invasion beyond the submucosa with EUS prior to endoscopic resection with EMR or ESD. Type 3 GCs should be managed as per recommendations for gastric adenocarcinoma. The treatment of advanced disease is multimodal.

CONCLUSIONS

Patients with gastric carcinoids should be discussed in a specialist neuroendocrine tumour multidisciplinary meeting to ensure all treatment options are explored in localised and advanced disease. Areas of controversy exist that need further research.

Current innovations in endoscopic therapy for the management of colorectal cancer: from endoscopic submucosal dissection to endoscopic full-thickness resection

Endoscopic submucosal dissection (ESD) is accepted as a minimally invasive treatment for colorectal cancer. However, due to technical difficulties and an increased rate of complications, ESD is not widely used in the colorectum. In some cases, endoscopic treatment alone is insufficient for disease control, and laparoscopic surgery is required. The combination of laparoscopic surgery and endoscopic resection represents a new frontier in cancer treatment. Recent developments in advanced polypectomy and minimally invasive surgical techniques will enable surgeons and endoscopists to challenge current practice in colorectal cancer treatment. Endoscopic full-thickness resection (EFTR) of the colon offers the potential to decrease the postoperative morbidity and mortality associated with segmental colectomy while enhancing the diagnostic yield compared to current endoscopic techniques. However, closure is necessary after EFTR and natural transluminal endoscopic surgery (NOTES). Innovative methods and new devices for EFTR and suturing are being developed and may potentially change traditional paradigms to achieve minimally invasive surgery for colorectal cancer. The present paper aims to discuss the complementary role of ESD and the future development of EFTR. We focus on the possibility of achieving EFTR using the ESD method and closing devices.

Expanding indications for ESD: mucosal disease (upper and lower gastrointestinal tract)

Endoscopic resection is now considered a curative procedure for early gastric cancer. In Japan, it has increasingly replaced surgical resection for this indication, although in the West it has not been universally accepted as a first-line treatment. Recently, endoscopic submucosal dissection has been increasingly applied to colorectal disease, although it has not become a standard therapeutic procedure for early colorectal carcinoma because of its technical difficulty, the relatively long procedure time required, and the risk of complications, such as perforation and bleeding.

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.

Risk factors for bleeding after endoscopic submucosal dissection of colorectal neoplasms

AIM: To investigate the risk factors for delayed bleeding following endoscopic submucosal dissection (ESD) treatment for colorectal neoplasms.

METHODS: We retrospectively reviewed the medical records of 317 consecutive patients with 325 lesions who underwent ESD for superficial colorectal neoplasms at our hospital from January 2009 to June 2013. Delayed post-ESD bleeding was defined as bleeding that resulted in overt hematochezia 6 h to 30 d after ESD and the observation of bleeding spots as confirmed by repeat colonoscopy or a required blood transfusion. We analyzed the relationship between risk factors for delayed bleeding following ESD and the following factors using univariate and multivariate analyses: age, gender, presence of comorbidities, use of antithrombotic drugs, use of intravenous heparin, resected specimen size, lesion size, lesion location, lesion morphology, lesion histology, the device used, procedure time, and the presence of significant bleeding during ESD.

RESULTS: Delayed post-ESD bleeding was found in 14 lesions from 14 patients (4.3% of all specimens, 4.4% patients). Patients with episodes of delayed post-ESD bleeding had a mean hemoglobin decrease of 2.35 g/dL. All episodes were treated successfully using endoscopic hemostatic clips. Emergency surgery was not required in any of the cases. Blood transfusion was needed in 1 patient (0.3%). Univariate analysis revealed that lesions located in the cecum (P = 0.012) and the presence of significant bleeding during ESD (P = 0.024) were significantly associated with delayed post-ESD bleeding. The risk of delayed bleeding was higher for larger lesion sizes, but this trend was not statistically significant. Multivariate analysis revealed that lesions located in the cecum (OR = 7.26, 95%CI: 1.99-26.55, P = 0.003) and the presence of significant bleeding during ESD (OR = 16.41, 95%CI: 2.60-103.68, P = 0.003) were independent risk factors for delayed post-ESD bleeding.

CONCLUSION: Location in the cecum and significant bleeding during ESD predispose patients to delayed post-procedural bleeding. Therefore, careful and additional management is recommended for these patients.

Is There an Indication for Surgical Resection in Colorectal Adenoma?

BACKGROUND

Due to the adenoma-carcinoma sequence, complete removal of colorectal polyps is essential.

METHOD

This article analyzes the role of surgery in the removal of colorectal adenoma.

RESULTS

Nowadays, most adenomas are removed properly by endoscopic methods. Also in the resection of giant polyps and recurrent adenoma endoscopic data is convincing. Therefore, surgical resection of colorectal adenomas is required in the case of endoscopic inaccessibility. Reasons for this may be the location of the polyp, incomplete endoscopic resection, or suspected malignancy. Endoscopic or limited surgical resection of malignant adenomas is acceptable only if 'low-risk' criteria are fulfilled. Otherwise oncologic radical resection is recommended. In general, radical resection is also necessary in the case of polyps that are not suitable for endoscopic removal, because here the rate of colorectal carcinoma is high.

CONCLUSION

If a surgical approach is necessary, minimally invasive surgery in the hands of an experienced laparoscopic surgeon is a suitable option. Adenomas in the lower two thirds of the rectum are suitable for transanal full-thickness resection. This is done by conventional resection or transanal endoscopic microsurgery. The histopathological preparation of these specimens provides diagnostic and therapeutic benefits, particularly compared to piecemeal resection of early carcinoma.

Advanced endoscopic resection in the colon: recent innovations, current limitations and future directions

The major health burden of colorectal cancer is reduced by colonoscopic polypectomy. The majority of polyps encountered are diminutive in size and easily removed; however, endoscopic removal of lesions >20 mm in size is also effective and safe. Techniques have progressed, advancing the boundaries of endoscopic therapy to include resection of circumferential lesions and selected submucosal invasive cancers. While there are cost and safety advantages over surgical management, specific limitations of endoscopic resection remain, chiefly bleeding, perforation and recurrence. Recent studies highlight the utility of risk stratification and demonstrate the effectiveness of endoscopic treatment of complications; however, strategies for prevention remain elusive. Prediction of submucosal invasive cancers through systematic assessment of lesion morphology and surface pattern is now established. Harnessing submucosal invasive cancer prediction and risk stratification allows a shift toward lesion-specific therapy, the next paradigm in the management of advanced colonic lesions.

Clinicopathological characteristics of laterally spreading colorectal tumor

BACKGROUND AND AIMS

Laterally spreading tumor (LST) is a colorectal pre-cancerous lesion. Previous studies have demonstrated distinct LST clinicopathological characteristics in different populations. This study evaluated clinicopathological characteristics of LST in a Chinese population.

METHODS

A total of 259 Chinese LST patients with 289 lesions were recruited for endoscopic and clinicopathological analyses.

RESULTS

Among these 289 lesions, 185 were granular type (LST-G), whereas 104 were non-granular type (LST-NG). LST-G lesions were further classified into homogeneous G-type and nodular mixed G-type, while LST-NG lesions were further classified into flat elevated NG-type and pseudo-depressed NG-type. Clinically, these four LST subtypes showed distinct clinicopathological characteristics, e.g., lesion size, location, or histopathological features (high-grade intraepithelial neoplasia and submucosal carcinoma). The nodular mixed G-type showed larger tumor size and higher incidence of high-grade intraepithelial neoplasia compared to the other three subtypes, while pseudo-depressed NG-type lesions showed the highest incidence of submucosal carcinoma. Noticeably, no diffidence was detected between the lesions of homogeneous G-type and flat elevated NG-type with regard to the histopathological features. Histology of the malignancy potential was associated with nodular mixed G-type [OR = 2.41, 95% CI (1.09-5.29); P = 0.029], flat elevated NG-type [OR = 3.49, 95% CI (1.41-8.22); P = 0.007], Diameter ≥30 mm [OR = 2.56, 95% CI (1.20-5.20); P = 0.009], Villous adenoma [OR = 2.76, 95% CI (1.01-7.58); P = 0.048] and serrated adenoma [OR = 6.99, 95% CI (1.81-26.98); P = 0.005].

CONCLUSION

Chinese LSTs can be divided into four different subtypes, which show distinct clinicopathological characteristics. Morphology, size and pathological characteristics are all independent predictors of advanced histology.

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.

Surgical management and chemoradiotherapy of T1 rectal cancer

T1 rectal cancer can be treated using various strategies. Endoscopic or transanal resection is the first choice of treatment when tumors are not associated with risk for lymph node metastasis. However, transabdominal resection with lymphadenectomy is recommended for tumors that do confer risk of lymph node metastasis. The prognosis after transabdominal resection is satisfactory, but various dysfunctions impair the postoperative quality of life. The standard treatment for T3-T4 rectal cancer is total mesorectal excision with preoperative chemoradiotherapy in Western countries and total mesorectal excision with laterallymph node dissection in Japan. Previous reports indicate that preoperative radiotherapy contributes to a lower rate of local recurrence, although overall survival is not affected. In addition, radiotherapy increases the prevalence of sexual dysfunction and fecal incontinence. The effect of perioperative chemoradiotherapy for T1-T2 rectal cancer remains unclear.

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.

High efficacy of endoscopic submucosal dissection for rectal laterally spreading tumors larger than 3 cm

BACKGROUND

Endoscopic submucosal dissection (ESD) was recently developed to allow en bloc resection of early neoplasia of the GI tract, including colorectal neoplasia. The endoscopic technique is technically demanding and not yet standardized, and new devices are needed.

OBJECTIVE

This study aimed to evaluate the efficacy and safety of a new device that combines the functions of injection and cutting.

DESIGN

Prospective, pilot, single-arm study.

METHODS

Consecutive patients with rectal laterally spreading tumors (LSTs) 3 cm or larger unsuitable for en bloc resection were enrolled. ESD was performed with a new device that allows cutting and coagulation as well as a needleless, tissue-selective mucosal and submucosal elevation through an axial water-jet channel.

MAIN OUTCOME MEASUREMENT

The primary endpoint of the study was the en bloc resection rate achieved with ESD in a Western hospital setting.

RESULTS

Overall, ESD was attempted in 40 consecutive patients (27 male, mean age 65.3 years) with rectal LSTs larger than 3 cm (72.5% LSTs, nongranular type, 5% depressed type, 22.5% protruding type). The mean lesion size was 46.8 ± 10.9 mm (range 33-80 mm). The mean procedure time was 86.1 ± 35.5 minutes (range 40-190 minutes). The en bloc resection rate was 90% (36/40). In the remaining patients, resection was completed with a piecemeal approach. The rate of curative resection (R0) was 32 of 40 LSTs (80%). Two patients with submucosal invasion were referred for surgery. Perforation occurred in 1 patient (2.5%), which was managed conservatively. Postoperative bleeding occurred in 2 patients (5%) and was treated by endoscopic hemostasis.

LIMITATIONS

Single-center study with a relatively small number of patients.

CONCLUSIONS

ESD is a safe and effective method to provide en bloc and curative resection of large rectal LSTs. The operating time and adverse event rate were comparable to those of previously published data from Japanese experts.

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.

Assessment of the validity of the clinical pathway for colon endoscopic submucosal dissection

AIM: To determine the effective hospitalization period as the clinical pathway to prepare patients for endoscopic submucosal dissection (ESD).

METHODS: This is a retrospective observational study which included 189 patients consecutively treated by ESD at the National Cancer Center Hospital from May 2007 to March 2009. Patients were divided into 2 groups; patients in group A were discharged in 5 d and patients in group B included those who stayed longer than 5 d. The following data were collected for both groups: mean hospitalization period, tumor site, median tumor size, post-ESD rectal bleeding requiring urgent endoscopy, perforation during or after ESD, abdominal pain, fever above 38  °C, and blood test results positive for inflammatory markers before and after ESD. Each parameter was compared after data collection.

RESULTS: A total of 83% (156/189) of all patients could be discharged from the hospital on day 3 post-ESD. Complications were observed in 12.1% (23/189) of patients. Perforation occurred in 3.7% (7/189) of patients. All the perforations occurred during the ESD procedure and they were managed with endoscopic clipping. The incidence of post-operative bleeding was 2.6% (5/189); all the cases involved rectal bleeding. We divided the subjects into 2 groups: tumor diameter ≥ 4 cm and < 4 cm; there was no significant difference between the 2 groups (P = 0.93, χ² test with Yates correction). The incidence of abdominal pain was 3.7% (7/189). All the cases occurred on the day of the procedure or the next day. The median white blood cell count was 6800 ± 2280 (cells/μL; ± SD) for group A, and 7700 ± 2775 (cells/μL; ± SD) for group B, showing a statistically significant difference (P = 0.023, t-test). The mean C-reactive protein values the day after ESD were 0.4 ± 1.3 mg/dL and 0.5 ± 1.3 mg/dL for groups A and B, respectively, with no significant difference between the 2 groups (P = 0.54, t-test).

CONCLUSION: One-day admission is sufficient in the absence of complications during ESD or early post-operative bleeding.

Efficacy of novel SB knife Jr examined in a multicenter study on colorectal endoscopic submucosal dissection

BACKGROUND AND AIM

Secure manipulation of forceps in endoscopic submucosal dissection (ESD) for colorectal tumors is sometimes hindered by the characteristics of that organ. SB knife Jr, which are scissor forceps using a mono-pole high frequency, were developed to avoid the difficulty of ESD operation in the colorectum. The aim of the present study was to examine the effectiveness of the SB knife Jr in colorectal ESD in 11 hospitals, mostly in northeastern Japan.

MATERIALS

One hundred and two colorectal tumors (49 non-granular laterally spreading tumor [LST] lesions, 39 granular LST lesions and 14 other lesions) that were resected by ESD operations using SB knife Jr between October 2009 and March 2010.

RESULTS

All tumors (102/102) were resected en bloc and could be observed in detail. The mean size of the resected pieces was 40.3 mm. The mean operation time was 54.2 min. Of the complications, one case of micro-perforation occurred during the manipulation of submucosal dissection, and this case was treated with clips in that operation. The rates of resection carried out only with SB knife Jr were 74.5% (76/102).

CONCLUSION

The novel ESD using SB knife Jr in the colorectum offers a breakthrough in resection techniques for not only expert endoscopists but also general endoscopists.

Effective training system in colorectal endoscopic submucosal dissection

Although colorectal endoscopic submucosal dissection (ESD) is superior to endoscopic mucosal resection (EMR) in en bloc resection rate, it is technically quite difficult because of the anatomical and histological characteristics of the colorectal wall. This difficulty prevents wide spread of the technique. Establishment of the training system for colorectal ESD is necessary to standardize training and to achieve wider acceptance of this technique. Herein, we describe our training system for colorectal ESD, and assess the validity of the training system for colorectal ESD, based on the clinical outcomes and learning curve of trainees. Our training system for colorectal ESD would help the spread of this procedure.

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.