Evaluation of endoscopic mucosal resection for laterally spreading rectal tumors

Endoscopic full-thickness resection versus endoscopic submucosal dissection for challenging colorectal lesions: a randomized trial

BACKGROUND AND AIMS

The optimal endoscopic resection method of challenging colorectal lesions (ie, adenomatous recurrences, nongranular laterally spreading tumors [LST-NGs], lesions without lifting sign <30 mm) is still under debate. The aim of this study was to directly compare endoscopic submucosal dissection (ESD) and endoscopic full-thickness resection (EFTR) for the resection of challenging colorectal lesions in a randomized trial.

METHODS

A multicenter, prospective, randomized study was performed in 4 Italian referral centers. Consecutive patients referred for endoscopic resection of challenging lesions were randomly assigned to undergo EFTR or ESD. Primary outcomes were complete (R0) resection and en bloc resection of lesions. Technical success, procedure time, procedure speed, area of the resected specimen, adverse event rate, and local recurrence rate at 6 months were also compared.

RESULTS

Overall, 90 patients were included in the study, equally representing the 3 challenging lesion types. Age and sex were comparable in the 2 groups. En bloc resection was obtained in 95.5% of the EFTR group and in 93.3% of the ESD group. R0 resection rate was comparable in the 2 groups (EFTR vs ESD, 42 [93.3%] vs 36 [80%]; P = .06). The EFTR group exhibited a significantly shorter total procedure time (25.6 ± 10.6 minutes vs 76.7 ± 26.4 minutes, P ≤ .01), as well as overall procedure speed (16.8 ± 11.8 mm2/min vs 11.9 ± 9.2 mm2/min, P = .03). The EFTR group had a significantly smaller mean lesion size (21.6 ± 8.3 mm vs 28.7 ± 7.7 mm, P ≤ .01). Adverse events were reported less frequently in patients in the EFTR group (4.44% vs 15.5%, P = .04).

CONCLUSIONS

EFTR is comparable to ESD in the treatment of challenging colorectal lesions in terms of safety and efficacy. EFTR is considerably faster than ESD in the treatment of nonlifting lesions and adenoma recurrences. (Clinical trial registration number: NCT05502276.).

Endoscopic Submucosal Dissection of Superficial Colorectal Neoplasms at "Challenging Sites" Using a Double-Balloon Endoluminal Interventional Platform: A Single-Center Study

BACKGROUND

Colonic endoscopic submucosal dissection (ESD) at "challenging sites" such as the cecum, ascending colon, and colonic flexures could be difficult even for expert endoscopists due to poor endoscope stability/maneuverability, steep angles, and thinner wall thickness. A double-balloon endoluminal intervention platform (EIP) has been introduced in the market to fasten and facilitate ESD, particularly when located at difficult sites. Here, we report our initial experience with an EIP comparing the outcomes of an EIP versus standard ESD (S-ESD) at "challenging sites".

MATERIALS AND METHODS

We retrospectively collected data on consecutive patients with colonic lesions located in the right colon and at flexures who underwent ESD in our tertiary referral center between March 2019 and May 2023. Endoscopic and clinical outcomes (technical success, en bloc resection rate, R0 resection rate, procedure time, time to reach the lesion, and adverse events) and 6-month follow-up outcomes were analyzed.

RESULTS

Overall, 139 consecutive patients with lesions located at these challenging sites were enrolled (EIP: 31 and S-ESD: 108). Demographic characteristics did not differ between groups. En bloc resection was achieved in 92.3% and 93.5% of patients, respectively, in the EIP and S-ESD groups. Both groups showed a comparable R0 resection rate (EIP vs. S-ESD: 92.3% vs. 97.2%). In patients undergoing EIP-assisted ESD, the total procedure time was shorter (96.1 [30.6] vs. 113.6 [42.3] minutes, p = 0.01), and the mean size of the resected lesions was smaller (46.2 ± 12.7 vs. 55.7 ± 17.6 mm, p = 0.003). The time to reach the lesion was significantly shorter in the EIP group (1.9 ± 0.3 vs. 8.2 ± 2.7 min, p ≤ 0.01). Procedure speed was comparable between groups (14.9 vs. 16.6 mm2/min, p = 0.29). Lower adverse events were observed in the EIP patients (3.8 vs. 10.2%, p = 0.31).

CONCLUSIONS

EIP allows results that do not differ from S-ESD in the resection of colorectal superficial neoplasms localized in "challenging sites" in terms of efficacy and safety. EIP reduces the time to reach the lesions and may more safely facilitate endoscopic resection.

Efficacy and safety of endoscopic resection techniques of large colorectal lesions: experience of a referral center in Italy

BACKGROUND

Endoscopic mucosal resection and submucosal dissection (ESD) are treatments of choice for superficial neoplastic colorectal lesions. Only a few studies have compared these techniques.

AIM

To compare the efficacy and safety of endoscopic piecemeal mucosal resection (EPMR), ESD and hybrid-endoscopic submucosal dissection (H-ESD) of large colorectal lesions in a Western endoscopic center.

METHODS

This is a retrospective analysis on a prospective medical database of consecutive colorectal superficial lesions larger than 20 mm, resected by EPMR, ESD or H-ESD collected from 2015 to 2019.

RESULTS

Two hundred twenty-nine colorectal lesions were included. All lesions were completely endoscopically resected, 65.9% by EPMR, 19.7% by ESD and 14.4% by H-ESD. Endoscopic control after the index procedure was available for 86.5% patients. Among these patients, 80% had a second follow-up colonoscopy. The overall recurrence rate was 13.2, 0 and 6.1% for EPMR, ESD and H-ESD respectively, with a significant difference between EPMR and ESD. All recurrences were endoscopically treated during follow-up procedures. Risk of complications was not significantly different between the three groups.

CONCLUSIONS

EPMR, ESD and H-ESD are effective and safe procedures. Recurrence rate in EPMR was higher but can be managed endoscopically with high success rates. EPMR is faster and technically simpler so should be considered a potential first-line therapy for colorectal superficial neoplastic lesions.

Long-term prognosis after endoscopic submucosal dissection for colorectal tumors in patients aged over 80 years

Background

In Japan, endoscopic submucosal dissection (ESD) is standardized for large colorectal tumors. However, its validity in the elderly population is unclear. We aimed to evaluate the safety and efficacy of ESD for colorectal tumors in elderly patients aged over 80 years.

Methods

ESD was performed on 178 tumors in 165 consecutive patients aged over 80 years between December 2008 and December 2018. We retrospectively evaluated the clinicopathological characteristics and clinical outcomes of ESD. We also assessed the prognosis of 160 patients followed up for more than 12 months.

Results

The mean patient age was 83.7 ± 3.1 years. The number of patients with comorbidities was 100 (62.5%). Among all patients, 106 (64.2%) were categorized as class 1 or 2 according to the American Society of Anesthesiologists classification of physical status (ASA-PS), and 59 (35.8%) were classified as class 3. The mean procedure time was 97.7 ± 79.3 min. The rate of histological en bloc resection was 93.8% (167/178). Delayed bleeding in 11 cases (6.2%) and perforation in 7 cases (3.9%) were treated conservatively. The 5-year survival rate was 89.9%. No deaths from primary disease (mean follow-up time: 35.3 ± 27.5 months) were observed. Overall survival rates were significantly lower in the non-curative resection group that did not undergo additional surgery than in the curative resection group (P = 0.0152) and non-curative group that underwent additional surgery (P = 0.0259). Overall survival rates were higher for ASA-PS class 1 or 2 patients than class 3 patients (P = 0.0105). Metachronous tumors (> 5 mm) developed in 9.4% of patients.

Conclusions

ESD for colorectal tumors in patients aged over 80 years is safe. Colorectal cancer-associated deaths were prevented although comorbidities pose a high risk of poor prognosis.

Comparison of the histopathological characteristics of large colorectal laterally spreading tumors according to growth pattern

OBJECTIVES

Colorectal laterally spreading tumors (LSTs) are widely recognized owing to their structural characteristics. This study aims to clarify the histopathological characteristics of large colorectal LSTs according to growth pattern.

METHODS

We studied 297 colorectal LSTs measuring ≥20 mm in diameter. The LSTs were classified into four types: granular homogenous type (LST-G-H), granular nodular mixed type (LST-G-M), non-granular flat elevated type (LST-NG-F), and non-granular pseudo-depressed type (LST-NG-PD). Retrospectively collected data were examined to compare the histopathological characteristics of LSTs according to the growth pattern.

RESULTS

LST-G-M lesions (142 lesions) were most common, followed by LST-NG-F (74 lesions), LST-G-H (61 lesions), and LST-NG-PD (20 lesions). The mean tumor diameter of LST-G lesions (38.5 ± 17.2 mm) was significantly greater than that of LST-NG lesions (26.3 ± 7.0 mm, P < 0.001). In particular, 45% of LST-G-M lesions were ≥40 mm in diameter. Adenomas accounted for 54% of LST-G-H lesions compared with only 10% of LST-NG-PD lesions. Pathological T1 carcinomas accounted for 55% of LST-NG-PD lesions and were not found among LST-G-H lesions.

CONCLUSIONS

The biological malignancy of colorectal LSTs differs considerably depending on the growth pattern even among large lesions and therefore should be considered when selecting treatment regimens.

Management of colorectal laterally spreading tumors: a systematic review and meta-analysis

Objective and study aims  To evaluate the efficacy and safety of different endoscopic resection techniques for laterally spreading colorectal tumors (LST). Methods  Relevant studies were identified in three electronic databases (PubMed, ISI and Cochrane Central Register). We considered all clinical studies in which colorectal LST were treated with endoscopic resection (endoscopic mucosal resection [EMR] and/or endoscopic submucosal dissection [ESD]) and/or transanal minimally invasive surgery (TEMS). Rates of en-bloc/piecemeal resection, complete endoscopic resection, R0 resection, curative resection, adverse events (AEs) or recurrence, were extracted. Study quality was assessed with the Newcastle-Ottawa Scale and a meta-analysis was performed using a random-effects model. Results  Forty-nine studies were included. Complete resection was similar between techniques (EMR 99.5 % [95 % CI 98.6 %-100 %] vs. ESD 97.9 % [95 % CI 96.1 - 99.2 %]), being curative in 1685/1895 (13 studies, pooled curative resection 90 %, 95 % CI 86.6 - 92.9 %, I ²  = 79 %) with non-significantly higher curative resection rates with ESD (93.6 %, 95 % CI 91.3 - 95.5 %, vs. 84 % 95 % CI 78.1 - 89.3 % with EMR). ESD was also associated with a significantly higher perforation risk (pooled incidence 5.9 %, 95 % CI 4.3 - 7.9 %, vs. EMR 1.2 %, 95 % CI 0.5 - 2.3 %) while bleeding was significantly more frequent with EMR (9.6 %, 95 % CI 6.5 - 13.2 %; vs. ESD 2.8 %, 95 % CI 1.9 - 4.0 %). Procedure-related mortality was 0.1 %. Recurrence occurred in 5.5 %, more often with EMR (12.6 %, 95 % CI 9.1 - 16.6 % vs. ESD 1.1 %, 95 % CI 0.3 - 2.5 %), with most amenable to successful endoscopic treatment (87.7 %, 95 % CI 81.1 - 93.1 %). Surgery was limited to 2.7 % of the lesions, 0.5 % due to AEs. No data of TEMS were available for LST. Conclusions  EMR and ESD are both effective and safe and are associated with a very low risk of procedure related mortality.

Metabolic syndrome is a risk factor for colorectal adenoma and cancer: a study in a White population using the harmonized criteria

BACKGROUND

Metabolic syndrome (MetS) has been associated with colorectal adenomas and cancer. However, MetS definitions have changed over time, leading to a heterogeneity of patients included in previous studies and a substantial inextensibility of observations across time or eastern and western populations. Our aim was to evaluate the association of 'harmonized' criteria-defined MetS and its individual components with colorectal neoplasia and cancer in a western population.

METHODS

In this multicenter, cross-sectional study, we prospectively evaluated consecutive outpatients who underwent open-access colonoscopy over a 3-month period. MetS was diagnosed according to the 2009 'harmonized' criteria.

RESULTS

Out of 5707 patients enrolled, we found 213 cancers (3.7%), 1614 polyps (28.3%), 240 nonpolypoid lesions (4.2%), 95 laterally spreading tumors (1.6%). Polyps presented histological low-grade dysplasia in 72.9% of samples, while in 9.8%, high-grade dysplasia or in situ carcinoma was present; dysplasia rates for nonpolypoid lesions were 66.2% (low-grade) and 2.9% (high-grade/in situ carcinoma), while for laterally spreading tumors, 29.6% and 37%, respectively. Overall, MetS prevalence was 41.6%. MetS correlated with both adenomas [odds ratio (OR): 1.76, 95% confidence interval (CI) 1.54-2.00] and cancer (OR: 1.92, 95% CI 1.42-2.58). MetS was the only risk factor for such colonic lesions in subjects younger than 50 years. For all colonic neoplasia, we found MetS and not its individual components to be significantly associated.

CONCLUSIONS

MetS is risk factor for cancer and adenoma in Whites, especially when younger than 50 years. MetS patients might be considered as a high-risk population also in colorectal cancer screening programs.

Evaluation of endoscopic mucosal resection and endoscopic submucosal dissection in submucosal lesions of the colon and rectum

Introduction

Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are commonly used for the minimally invasive treatment of submucosal lesions of the gastrointestinal tract.

Aim

To evaluate the safety, efficacy, outcome and recurrence rate of EMR and ESD for mucosal and submucosal lesions in the colon and rectum.

Material and methods

Records of 26 patients who underwent ESD and EMR for mucosal and submucosal lesions in the colon and rectum between January 2013 and March 2018 in our endoscopy unit were retrospectively reviewed.

Results

A total of 26 patients (6 female and 20 male) were evaluated. The mean age of the patients was 58.03 ±15.19 (21–80). Fifteen patients underwent ESD and EMR for rectal lesions. Tubular adenomas were found in 3 of these patients, tubulo-villous adenomas in 2, inflammatory polyps in 1, neuroendocrine tumors in 2 and carcinomas in 7 (intramucosal, in-situ and invasive). Eleven patients underwent ESD and EMR for colonic lesions. Villous adenomas were found in 2 of these patients, tubular adenoma showing dysplasia in 2, tubulo-villous adenomas showing dysplasia in 1 and carcinoma (in-situ, invasive and intramucosal) in 6. Two lesions were resected with secondary transanal local excision to obtain free margins. The follow-up period was 3 to 48 months and no recurrence was observed.

Conclusions

The EMR and ESD are reliable minimally invasive techniques with a low rate of complications and short hospital stay in the treatment of colon and rectal lesions, including early stage carcinomas of different size and morphology.

Colorectal polyps located across a fold are difficult to resect completely using endoscopic mucosal resection: A propensity score analysis

Background

Incomplete polyp resection during colorectal endoscopic mucosal resection (EMR) might contribute to the development of interval cancer.

Objective

This retrospective study aimed to determine the incidence of incomplete polyp resection during EMR of colorectal polyps located across a fold compared with that of colorectal polyps located between folds.

Methods

In total, 262 patients with 262 lesions that were ≥10 mm in diameter and treated with conventional EMR were enrolled. The main outcome was the incidence of incomplete polyp resections. Propensity score matching and inverse probability of treatment weighting (IPTW) were performed to reduce the effects of selection bias.

Results

Fifty-seven lesions (21.8%) were incompletely resected. After propensity score matching, the lesions located across a fold were at higher risk of incomplete resection than those between folds (26/68, 38.2% vs 7/68, 10.3%; odds ratio (OR): 3.71; 95% confidence interval (CI): 1.61-8.56; p < 0.01). These findings persisted after adjusting for the differences at baseline using the IPTW method (OR: 3.63; 95% CI: 1.72-7.63; p = 0.001).

Conclusions

There is an increased risk of an incomplete polyp resection for a colorectal polyp that is located across a fold compared with that for a polyp that is located between folds.

Perforation and Postoperative Bleeding Associated with Endoscopic Submucosal Dissection in Colorectal Tumors: An Analysis of 398 Lesions Treated in Saga, Japan

Objective The aim of this study was to clarify the safety of colorectal endoscopic submucosal dissection (ESD) during the era of health insurance coverage starting from April 2012 in Japan. Methods Between April 2012 and May 2016, ESD was applied to 398 lesions in 373 patients. Risk factors for serious complications of colorectal ESD, perforation and post-ESD bleeding, were evaluated focusing on the resected specimen size, location, growth pattern, invasion depth, histopathology, postoperative clipping, and procedure time. In addition, the relationship between serious complications and patients' background characteristics was analyzed. Results Among 373 patients, perforation occurred in 12 patients and post-ESD bleeding in 19 patients. A univariate analysis showed that the risk factors for perforation were the lesion size, the resected specimen size, and a long operation time. A multivariate analysis showed that a long operation time was a risk factor for perforation during colorectal ESD. A univariate analysis indicated that significant risk factors for postoperative bleeding were a long operation time, rectal lesion, and cancer. All patients with serious complications were treated by an endoscopic procedure without blood transfusion or the need to convert to open surgery. Conclusion The present study suggests that colorectal ESD may be accepted with relative safety in Japan as a common therapeutic approach for early colorectal cancer.

Clinical outcomes of endoscopic submucosal dissection for large colorectal laterally spreading tumors in older adults

BACKGROUND AND AIMS

The colorectal endoscopic submucosal dissection (ESD) remains technically challenging, especially for older patients who frequently encounter complex chronic diseases and have a loose colon. However, only limited number of studies are available for the safety of ESD in older patients with especially large laterally spreading tumors. Therefore, in this retrospective study, we compared the outcomes of ESD for laterally spreading tumors (LST) ≥3cm(cm) in older patients to that in younger patients.

METHODS

Consecutive patients with LSTs 3cm or larger were enrolled for from May 2010-2016. These patients were divided into two groups: the younger group (<65years) and the older group (≥65years). The clinicopathologic findings and the outcomes of ESD procedures were compared between the two groups.

RESULTS

A total of 70 patients in the younger group and 73 patients in the older group were treated by ESD for colorectal LSTs larger than 3cm. No significant differences were observed in the gender ratio, tumor morphological type, tumor location, and tumor size between the two groups. The en bloc resection rates were 85.7 and 89.0%, respectively, without a significant difference. The procedural time was similar between the younger and older patients (71.8±34.7min vs. 70.6±29.5min). The duration of hospital stay was not significantly different between the two groups (4.1±2.2days vs. 4.4±2.5days). No significant differences were observed between the two groups with respect to ESD-related complications including delayed bleeding, perforation, and stricture.

CONCLUSIONS

ESD appears to be an effective and safe method for LSTs larger than 3cm in older patients.

Endoscopic treatment outcomes of laterally spreading tumors with a skirt (with video)

BACKGROUND AND AIMS

A "skirt" is a slightly elevated flat lesion with wide pits occasionally observed at the margin of laterally spreading tumors (LSTs). However, the endoscopic treatment outcomes of LSTs with skirts have not been clarified. The aim of this study was to evaluate the endoscopic treatment outcomes of LSTs with skirts.

METHODS

Between February 2006 and March 2014, 996 LSTs were retrospectively examined to assess the clinicopathologic characteristics, procedure time, en bloc resection rate, R0 resection rate, adverse events, and local recurrence rate of endoscopic submucosal dissection (ESD) and of endoscopic resection.

RESULTS

Endoscopic treatment was performed in 35 cases of LSTs with skirts (ratio of ESD to endoscopic piecemeal mucosal resection [EPMR], 32:3) and 961 cases of LSTs without skirts (ratio of ESD to EMR to EPMR to polypectomy, 381:275:114:191). LSTs with a skirt were associated with a significantly higher recurrence rate (P < .01). In both ESD and EPMR, LSTs with a skirt were associated with a higher recurrence rate when compared with LSTs without a skirt (odds ratio, 12.7; P = .032, and odds ratio, 12.3; P = .061, respectively). Multivariate analysis demonstrated that the presence of the skirt and piecemeal resection were significant predictors of local recurrence.

CONCLUSIONS

LSTs with skirts had a significantly higher local recurrence rate after endoscopic treatment compared with LSTs without skirts, especially after EPMR. Therefore, ESD should be recommended as an endoscopic treatment for LSTs with skirts to minimize local recurrence.

Analysis of molecular alterations in laterally spreading tumors of the colorectum

BACKGROUND

Colorectal laterally spreading tumors (LSTs) are classified into LST-Gs and LST-NGs, according to macroscopic findings. In the present study, we determined the genetic and epigenetic alterations within colorectal LSTs and protruding adenomas.

METHODS

A crypt isolation method was used to isolate DNA from tumors and normal glands of 73 macroscopically verified colorectal LSTs (histologically defined adenomas; 38 LST-Gs and 35 LST-NGs) and 36 protruding adenomas. The DNA was processed using polymerase chain reaction (PCR) microsatellite assays, single-strand conformation polymorphism (SSCP) assays, and pyrosequencing to detect chromosomal allelic imbalance (AI), mutations in APC, KRAS, and TP53, and the methylation of MLH1, MGMT, CDKN2A, HPP1, RASSF2A, SFRP1, DKK1, ZFP64, and SALL4 genes. In addition, methylation status was examined using the following set of markers: MIN1, MINT2, MINT31, MLH1, and CDKN2A (with classification of negative/low and high). Microsatellite instability (MSI) was also examined.

RESULTS

5q AI and methylation of the SFRP1 and SALL4 genes were common molecular events in both LST-Gs and LST-NGs. Neither MSI nor mutations in BRAF ware observed in the LSTs. TP53 mutations were rarely found in LSTs. The frequencies of KRAS and APC mutations and the methylation levels of ZFP64, RASSF2A, and HPP1 genes were significantly higher in LST-Gs than in LST-NGs. Protruding adenomas showed alterations common to LST-Gs. Negative/low methylation status was common among the three types of tumors.

CONCLUSION

Combined genetic and epigenetic data suggested that the molecular mechanisms of tumorigenesis were different between LST-Gs and LST-NGs.

Comparing endoscopic mucosal resection with endoscopic submucosal dissection: the different endoscopic techniques for colorectal tumors

BACKGROUND

Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are used for the removal of colorectal tumors. There are no current guidelines or consensus on the optimal treatment strategy for these lesions. A meta-analysis was conducted to compare the effectiveness and safety of ESD and EMR for colorectal tumors.

METHODS

For the years 1966 until October 2014, Medline, PubMed, Scopus, Web of Science, and Cochrane Central Register of Controlled Trials were searched for articles comparing the effectiveness and safety of ESD and EMR. STATA 11.0 and RevMan 5.0 were used for meta-analysis and publication bias.

RESULTS

Seventeen articles were included in this meta-analysis. ESD was more effective than EMR in endoscopic complete resection rate (odds ratio [OR] = 2.81; 95% confidence interval [CI], 1.39-5.70; Z = 2.86; P = 0.004) and pathologic complete resection rate (OR = 2.81; 95% CI, 1.39-5.70; Z = 2.86; P = 0.004). ESD resulted in a higher perforation rate (OR = 5.27; 95% CI, 2.75-10.08; Z = 5.01; P < 0.00001) and a lower recurrence rate (OR = 0.14; 95% CI, 0.06-0.30; Z = 5.04; P < 0.00001). The tumor size was larger in the ESD group (OR = 3.09; 95% CI, 1.54-4.63; Z = 3.92; P < 0.0001), and the procedure time was longer in the ESD group (OR = 21.39; 95% CI, 10.33-32.46; Z = 3.79; P = 0.0002). But bleeding rate did not differ significantly (OR = 1.34; 95% CI, 0.81-2.20; Z = 1.14; P = 0.25). There was no publication bias analyzed by Begg test and Egger test.

CONCLUSIONS

The study indicates that ESD is the better treatment for colorectal tumors for its higher complete resection rate despite the longer procedure time and higher perforation rate.

A pilot study of fluorescent imaging of colorectal tumors using a γ-glutamyl-transpeptidase-activatable fluorescent probe

Backgrounds/Aim: Colorectal laterally spreading tumors (LSTs) are sometimes difficult to visualize even with image-enhanced endoscopy. γ-Glutamyl-transpeptidase (GGT) is a cell surface-associated enzyme that is overexpressed in various types of human cancers. Furthermore, GGT expression is higher in colorectal cancer cells than in normal colorectal mucosa. γ-Glutamyl hydroxymethyl rhodamine green (gGlu-HMRG), an activatable fluorescent probe, is nonfluorescent under a neutral pH and normal cellular environment; however, it turns highly fluorescent upon reaction with GGT. We evaluated ex vivo fluorescent imaging of colorectal LSTs using this GGT-activatable fluorescent probe.

METHODS

Between March 2013 and March 2014, 30 endoscopically resected colorectal LSTs were prospectively included in this study. Each was analyzed by first taking a baseline image before spraying, then spraying with gGlu-HMRG onto the freshly resected specimen, and finally taking fluorescent images 15 min after spraying with a dedicated imaging machine.

RESULTS

Of the LSTs, 67% rapidly showed positive fluorescent activity. These activities were shown in adenoma (54%) and carcinoma in adenoma (76%), and in LST-granular type (80%) and LST-nongranular type (40%).

CONCLUSION

Topically spraying gGlu-HMRG enabled rapid and selective fluorescent imaging of colorectal tumors owing to the upregulated GGT activity in cancer cells.

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.

Practice parameters for early colon cancer management: Italian Society of Colorectal Surgery (Società Italiana di Chirurgia Colo-Rettale; SICCR) guidelines

Early colon cancer (ECC) has been defined as a carcinoma with invasion limited to the submucosa regardless of lymph node status and according to the Royal College of Pathologists as TNM stage T1 NX M0. As the potential risk of lymph node metastasis ranges from 6 to 17% and the preoperative assessment of lymph node metastasis is not reliable, the management of ECC is still controversial, varying from endoscopic to radical resection. A meeting on recent advances on the management of colorectal polyps endorsed by the Italian Society of Colorectal Surgery (SICCR) took place in April 2014, in Genoa (Italy). Based on this material the SICCR decided to issue guidelines updating the evidence and to write a position statement paper in order to define the diagnostic and therapeutic strategy for ECC treatment in context of the Italian healthcare system.

Evidence-based clinical practice guidelines for management of colorectal polyps

BACKGROUND

Recently in Japan, the morbidity of colorectal polyp has been increasing. As a result, a large number of cases of colorectal polyps that are diagnosed and treated using colonoscopy has now increased, and clinical guidelines are needed for endoscopic management and surveillance after treatment.

METHODS

Three committees [the professional committee for making clinical questions (CQs) and statements by Japanese specialists, the expert panelist committee for rating statements by the modified Delphi method, and the evaluating committee by moderators] were organized. Ten specialists for colorectal polyp management extracted the specific clinical statements from articles published between 1983 and September 2011 obtained from PubMed and a secondary database, and developed the CQs and statements. Basically, statements were made according to the GRADE system. The expert panel individually rated the clinical statements using a modified Delphi approach, in which a clinical statement receiving a median score greater than seven on a nine-point scale from the panel was regarded as valid.

RESULTS

The professional committee created 91CQs and statements for the current concept and diagnosis/treatment of various colorectal polyps including epidemiology, screening, pathophysiology, definition and classification, diagnosis, treatment/management, practical treatment, complications and surveillance after treatment, and other colorectal lesions (submucosal tumors, nonneoplastic polyps, polyposis, hereditary tumors, ulcerative colitis-associated tumor/carcinoma).

CONCLUSIONS

After evaluation by the moderators, evidence-based clinical guidelines for management of colorectal polyps have been proposed for 2014.

Endoscopic mucosal resection with circumferential incision for the treatment of large sessile polyps and laterally spreading tumors of the colorectum

Background/Aims

Endoscopic mucosal resection (EMR) is the standard treatment for colorectal polyps such as adenomas and early cancers with no risk of lymph node metastasis. However, endoscopic resection of large colorectal polyps (≥20 mm diameter) is difficult to perform. We evaluated the clinical outcomes of EMR with circumferential incision (EMR-CI) for the resection of large sessile polyps (Is) and laterally spreading tumors (LSTs) in the colorectum.

Methods

Between February 2009 and March 2011, we resected 80 large colorectal polyps by EMR-CI. We retrospectively investigated the en bloc resection rate, histologic complete resection rate, recurrence rate, and complications.

Results

The median polyp size was approximately 25 mm (range, 20 to 50), and the morphologic types included Is (13 cases), LST-granular (37 cases), and LST-nongranular (30 cases). The en bloc and complete histologic resection rates were 66.3% and 45.0%, respectively. The recurrence rate was 0% (median follow-up duration, 23 months), and perforation occurred in five cases (6.3%).

Conclusions

EMR-CI is an effective treatment modality for 20 to 30 mm-sized colorectal polyps, and may be considered as a second line therapeutic option if ESD is difficult.

Endoscopic and laparoscopic cooperative surgery for large colorectal laterally spreading tumors

AIM: To investigate the value of endoscopic and laparoscopic cooperative surgery in the treatment of colorectal laterally spreading tumors (LSTs).

METHODS: A retrospective analysis of 21 patients with colorectal LSTs lager than 3 cm treated by endoscopic and laparoscopic cooperative surgery was performed.

RESULTS: According to endoscopic biopsy, indigo carmine staining and endoscopic ultrasonography, laparoscopic assisted endoscopic resection was performed in 9 cases, endoscopic assisted laparoscopic operation in 7 cases, including 1 case that underwent additional laparoscopic radical operation, and simultaneous endoscopic and laparoscopic treatment in 5 cases. Intraoperative frozen section pathological examination revealed that there were 13 (61.9%) cases of low-grade intraepithelial dysplasia, 7 (33.3%) cases of high-grade intraepithelial dysplasia, and 1 (4.8%) case of carcinoma. Main lesions were mixed type nodules (42.9%) and flat elevated type (38.1%). The average follow-up time was 18 mo, and no metastasis or recurrence was found during follow-up.

CONCLUSION: Endoscopic and laparoscopic cooperative surgery offers a minimally invasive, effective and safe therapeutic approach for LSTs lager than 3 cm.

Endoscopic submucosal dissection for colorectal neoplasms: A review

The introduction of colorectal endoscopic submucosal dissection (ESD) has expanded the application of endoscopic treatment, which can be used for lesions with a low metastatic potential regardless of their size. ESD has the advantage of achieving en bloc resection with a lower local recurrence rate compared with that of piecemeal endoscopic mucosal resection. Moreover, in the past, surgery was indicated in patients with large lesions spreading to almost the entire circumference of the rectum, regardless of the depth of invasion, as endoscopic resection of these lesions was technically difficult. Therefore, a prime benefit of ESD is significant improvement in the quality of life for patients who have large rectal lesions. On the other hand, ESD is not as widely applied in the treatment of colorectal neoplasms as it is in gastric cancers owing to the associated technical difficulty, longer procedural duration, and increased risk of perforation. To diversify the available endoscopic treatment strategies for superficial colorectal neoplasms, endoscopists performing ESD need to recognize its indications, the technical issues involved in its application, and the associated complications. This review outlines the methods and type of devices used for colorectal ESD, and the training required by endoscopists to perform this procedure.

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.

Clinicopathological differences of laterally spreading tumors arising in the colon and rectum

PURPOSE

Laterally spreading tumors (LST) have been recognized worldwide. The aim of our retrospective study was to evaluate the clinicopathological differences of LST arising in the colon and rectum.

METHODS

We investigated the clinical records of consecutive patients with LST that were endoscopically or surgically resected at our hospital between February 2006 and March 2011. LST were classified into three types: granular-homogenous (LST-GH), granular-nodular mixed (LST-GM), and nongranular (LST-NG) types. We also defined the hardly elevated flat lesion with a dilated pit pattern that occurs at the margins of LST as the "skirt." The clinicopathological characteristics of the LST arising in the colon and rectum, including the presence of the skirt, were compared.

RESULTS

A total of 496 colorectal LST in 435 patients were examined. LST-GM was predominant in the rectum, whereas LST-NG was predominant in the colon (p < 0.001). The mean tumor size was larger in the rectum (39.3 ± 17.9 mm) than the colon (25.8 ± 13.6 mm) (p < 0.001). Low-grade dysplasia frequency was lower in the rectum than the colon (4 vs. 37%, p < 0.001). The skirt was identified in 15 lesions (3.0%), with a higher incidence in the rectum than the colon (17 vs. 0.5%, p < 0.001). The skirt was found only in LST-GM.

CONCLUSIONS

A greater proportion of LST-GM, greater mean size, and lower incidence of low-grade dysplasia were found in rectal LST. The skirt was a novel and unique finding, primarily observed in rectal LST-GM cases.

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.

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.

Colorectal laterally spreading tumors by computed tomographic colonography

To date, few reports focused primarily on detecting colorectal laterally spreading tumors (LSTs) have been published. The aim of this study was to determine the visibility of LSTs on computed tomographic colonography (CTC) compared with that on colonoscopy as a standard. We retrospectively reviewed and matched data on endoscopic and CTC reports in 157 patients (161 LSTs) who received a multidetector CT scan using contrast media immediately after total colonoscopy at the National Cancer Center Hospital in Tokyo, Japan, between December 2005 and August 2010. The results of the total colonoscopy were known at the time of the CTC procedure and reading. Of the 161 LSTs detected on colonoscopy, 138 were observed and matched by CTC (86%). Of the 91 granular type LSTs (LST-Gs), 88 (97%) were observed and matched, while of the 70 non-granular type LSTs (LST-NGs), 50 (71%) were observed and matched by CTC (p < 0.0001). CTC enabled observation of 73% (22/30) of 20–29 mm, 83% (35/42) of 30–39 mm, 88% (49/56) of 40–59 mm, and 97% (32/33) of ≥60 mm tumors. The rate of observed LSTs by CTC was 86% (97% of LST-G, 71% of LST-NG) of the LSTs found during total colonoscopy.

Endoscopic mucosal resection in high- and low-volume centers: a prospective multicentric study

BACKGROUND

Endoscopic mucosal resection (EMR) is an effective therapeutic technique well-standardized worldwide for the treatment of gastrointestinal neoplasm limited to the mucosal layer. To date, no study has compared technical and clinical differences based on the number of EMRs performed per year. This study aimed to compare EMR technical success, complications, and clinical outcome between low-volume centers (LVCs) and high-volume centers (HVCs). A total of nine endoscopic centers were included in the study.

METHODS

This prospective study investigated consecutive patients with sessile polyps or flat colorectal lesions 1 cm or larger referred for EMR.

RESULTS

A total of 427 lesions were resected in 384 patients at nine endoscopic centers. Males accounted for 60.4% and females for 39.6% of the patients. Most of the EMRs (84.8%) were performed in HVCs and only 15.2% in LVCs. All the lesions were resected in only one session. Argon plasma coagulation was performed on the margins of piecemeal resection in 15.7% of the patients in HVCs only. Complete excision was achieved for 98.6% of the lesions in HVCs and 98.8% of the lesions in LVCs. The complication rate was 4.4% in HVCs and 4.6% in LVCs (p = 0.94). Delayed bleeding occurred in 2.5% of the HVC cases and 3.1% of the LVC cases. Perforation occurred in 1.9% of the HVC cases and 1.5% of the LVC cases (p = 1.00). Recurrences were experienced with 15% of the lesions: 15.5% in HVCs and 14% in LVCs (p = 0.79).

CONCLUSIONS

The study showed that EMR can be performed also in LVC.

Colorectal endoscopic submucosal dissection: is it suitable in western countries?

Endoscopic submucosal dissection (ESD) represents a significant advance in therapeutic endoscopy with the major advantage being the ability to achieve a higher en bloc resection rate for early stage lesions. Western endoscopists infrequently perform colorectal ESD (CR-ESD) because of the greater technical difficulty involved, longer procedure times, and increased risk of perforation. Specialized training and sufficient clinical experience are necessary to successfully perform ESDs, but a systematic education and training program has still not been established in Japan or elsewhere in the world. Experts generally acknowledge that the stomach is the first organ in which endoscopists should begin performing ESDs. The incidence and detection rates for early stage gastric cancer are significantly higher in Japan than in western countries, so Japanese endoscopists have a greater opportunity to perform gastric ESDs than their western counterparts. It is logical to ask, therefore, whether CR-ESD can be effectively applied in western countries. Based on a review of the relevant literature and our practical perspective, we have focused on the progress made in performing CR-ESD, its indications, training methods, and learning curve. Use of animal gastric and colon models is strongly recommended along with accumulating the necessary experience from the rectum to the colon on a step-by-step basis. It is reasonable to assume that an increasing number of CR-ESDs will be performed by western endoscopists in the foreseeable future given the continuing development of new techniques, and the refinement of instruments and other technologically advanced devices together with the creation of even more effective submucosal injection agents.

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.

Predictive factors of local recurrence after endoscopic piecemeal mucosal resection

BACKGROUND

Endoscopic piecemeal mucosal resection (EPMR) is a widely accepted treatment for colorectal tumefaction. However, as it is associated with a significant recurrence rate, the technique remains controversial. The purpose of our study was to evaluate the risk factors for the local recurrence of colorectal neoplasms after EPMR.

METHODS

The study population of our retrospective evaluation comprised 222 patients who had undergone EPMR from January 2002 to July 2007 and who had had at least 1 surveillance colonoscopy 3-6 months after the initial treatment.

RESULTS

Local recurrence was detected in 42 patients (19%) between 6 and 15 months after EPMR. Our multivariate analysis revealed that the resection of 5 or more neoplasm specimens, compared with fewer than 5, was 3 times more likely to result in local recurrence (P = 0.005). No statistically significant correlation of local recurrence with lesion size, location, macroscopic type, or histology was detected.

CONCLUSION

The removal of 5 or more neoplasm specimens is an independent risk factor for local recurrence after EPMR. Careful colonoscopic surveillance should be performed after multiple piecemeal resection.

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.

Efficacy of endoscopic mucosal resection with circumferential incision for patients with large colorectal tumors

BACKGROUND & AIMS

Treatment of large colorectal neoplasms (>20 mm in diameter) by conventional endoscopic mucosal resection (EMR) often results in piecemeal resection that requires further intervention. We evaluated the efficacy of EMR with circumferential incision (CEMR).

METHODS

From March 2008-July 2009, we resected 24 large colorectal neoplasms measuring 20-40 mm in diameter by using the CEMR technique. CEMR was performed by using a ball-tip bipolar needle knife with a snaring technique. After the injection of glycerol into the submucosal layer, a circumferential incision was made, and the neoplasm was resected by snaring. All lesions that showed a noninvasive pattern were diagnosed by magnifying chromoendoscopy as adenomas or intramucosal or submucosal superficial cancers. The number of en bloc resections and complications and the overall procedure time were determined.

RESULTS

The proportions of en bloc and 2-piece resections by CEMR were 67% (16/24) and 17% (4/24), respectively. The median (interquartile range) time for CEMR completion was 40 minutes (30-63 minutes). No postsurgery complications occurred in any patient.

CONCLUSIONS

CEMR might provide acceptable clinical outcomes for patients with large colorectal neoplasms. It results in a low incidence of incomplete treatments and low risk of complications.

Current status in the occurrence of postoperative bleeding, perforation and residual/local recurrence during colonoscopic treatment in Japan

Bleeding, perforation, and residual/local recurrence are the main complications associated with colonoscopic treatment of colorectal tumor. However, current status regarding the average incidence of these complications in Japan is not available. We conducted a questionnaire survey, prepared by the Colorectal Endoscopic Resection Standardization Implementation Working Group, Japanese Society for Cancer of the Colon and Rectum (JSCCR), to clarify the incidence of postoperative bleeding, perforation, and residual/local recurrence associated with colonoscopic treatment. The total incidence of postoperative bleeding was 1.2% and the incidence was 0.26% with hot biopsy, 1.3% with polypectomy, 1.4% with endoscopic mucosal resection (EMR), and 1.7% with endoscopic submucosal dissection (ESD). The total incidence of perforation was 0.74% (0.01% with the hot biopsy, 0.17% with polypectomy, 0.91% with EMR, and 3.3% with ESD). The total incidence of residual/local recurrence was 0.73% (0.007% with hot biopsy, 0.34% with polypectomy, 1.4% with EMR, and 2.3% with ESD). Colonoscopic examination was used as a surveillance method for detecting residual/local recurrence in all hospitals. The surveillance period differed among the hospitals; however, most of the hospitals reported a surveillance period of 3-6 months with mainly transabdominal ultrasonography and computed tomography in combination with the colonoscopic examination.

Polyp surveillance

Surveillance after colonic polypectomy is important to detect and remove missed synchronous polyps and cancers and new metachronous polyps or cancers. The authors review methods of surveillance and the risk of recurrent adenomas and provide surveillance recommendations.

Large endoscopic mucosal resection for colorectal tumors exceeding 4 cm

AIM: To evaluate the feasibility and the outcome of endoscopic mucosal resection (EMR) for large colorectal tumors exceeding 4 cm (LCRT) undergoing piecemeal resection.

METHODS: From January 2005 to April 2008, 146 digestive tumors larger than 2 cm were removed with the EMR technique in our department. Of these, 34 tumors were larger than 4 cm and piecemeal resection was carried out on 26 colorectal tumors. The mean age of the patients was 71 years. The mean follow-up duration was 12 mo.

RESULTS: LCRTs were located in the rectum, left colon, transverse colon and right colon in 58%, 15%, 4% and 23% of cases, respectively. All were sessile tumors larger than 4 cm with a mean size of 4.9 cm (4-10 cm). According to the Paris classification, 34% of the tumors were type Is, 58% type IIa, 4% type IIb and 4% type IIc. Pathological examination showed tubulous adenoma in 31%, tubulo-villous adenoma in 27%, villous adenoma in 42%, high-grade dysplasia in 38%, in situ carcinoma in 19% of the cases and mucosal carcinoma (m2) in 8% of the cases. The two cases (7.7%) of procedural bleeding that occurred were managed endoscopically and one small perforation was treated with clips. During follow-up, recurrence of the tumor occurred in three patients (12%), three of whom received endoscopic treatment.

CONCLUSION: EMR for tumors larger than 4 cm is a safe and effective procedure that could compete with endoscopic submucosal dissection, despite providing incomplete histological assessment.

Treatment strategy for laterally spreading tumors in Japan: before and after the introduction of endoscopic submucosal dissection

BACKGROUND AND AIMS

Laterally spreading tumors (LST) in the colorectum are considered good candidates for endoscopic resection (ER). Because LST-non-granular (NG) tumors show multifocal invasion into the submucosal layer, en bloc resection is necessary for adequate histopathological evaluation. Therefore, surgical resection has been recommended when a lesion is suspected to be an invasive cancer and too large to resect en bloc. The aim of the present study was to evaluate whether the introduction of colorectal ESD, which was developed for en bloc resection of early gastric cancers, could improve the en bloc resection rate of large LST-NG-type tumors and reduce the surgical resection rate.

METHODS

Between January 1999 and December 2005, a total of 166 LST-NG-type tumors measuring > or = 20 mm in 161 patients were included in this study. The en bloc resection rate and the surgical resection rate were historically compared between two periods, before and after the introduction of ESD.

RESULTS

The en bloc resection rate for ER lesions was significantly higher in the latter period (35.0% [14/40]vs 76.5% [75/98]; P < 0.001), and the rate of surgery for adenomas and intramucosal or sm minute cancers was significantly lower in the latter period (20.0% [10/50]vs 1.1% [1/89]; P < 0.001).

CONCLUSIONS

The introduction of colonic ESD was able to change our treatment strategy for LST, improving the en bloc resection rate and reducing the surgical resection rate.

Therapeutic strategy for colorectal laterally spreading tumor

Most colorectal tumors larger than 20 mm in diameter are called laterally spreading tumors (LST), most of which are adenomatous lesions. Laterally spreading tumors are classified into two types according to their morphology, granular type (LST-G) and non-granular type (LST-NG). Each type has two subtypes. The former consists of a 'homogenous type' and a 'nodular mixed type', while the latter consists of a 'flat elevated (FE) type' and a 'psedodepressed (PD) type'. In LST-G and LST-NG FE types, type V pit pattern with magnification enables the recognition of the carcinomatous or submucosal invasive area. Most of these adenomatous large lesions can be cured by scheduled endoscopic piecemeal mucosal resection (EPMR). However, LST-G with large whole nodular type or type V pit pattern, which cannot be resected en bloc with a snare, is an indication for endoscopic submucosal dissection (ESD). The LST-NG PD has a high frequency of submucosal invasion and the submucosal invasive area cannot be recognized correctly in the pseudodepression with magnification prior to endoscopic treatment. Therefore, en bloc resection with ESD should be applied to LST-NG PD. The therapeutic strategy for choosing between EPMR and ESD for large LST lesions should therefore be determined based on the macroscopic findings of their subtype and pit pattern findings.

Endoscopic submucosal dissection for colorectal epithelial neoplasm

BACKGROUND

Endoscopic submucosal dissection (ESD), a new widely accepted method for treating early gastric cancer, was developed to increase the en bloc rate, especially for lesions larger than 20 mm in diameter. This study aimed to evaluate the efficacy and safety of ESD for colorectal epithelial neoplasms.

METHODS

From July 2006 to December 2007, ESD was indicated for patients with colorectal epithelial neoplasms larger than 20 mm in diameter. The rates of curative en bloc resection, the procedure time, and the incidence of complications were investigated.

RESULTS

A total of 74 colorectal epithelial neoplasms were resected by ESD. The mean diameter of these lesions was 32.6 mm (range, 20-85 mm). The rate of en bloc resection was 93.2% (69/74), and the mean ESD procedure time was 110 min (range, 80-185 min). None of patients had massive hemorrhage during ESD, and only one patient (1.4%) bled 8 days after ESD. Six patients experienced perforation, and all except one recovered after several days of conservative treatment. The patient who did not recover underwent urgent surgery. The perforation rate was 8.1% (6/74). All the patients were followed up. Healing of the artificial ulcer was confirmed, and with no lesion residue or recurrence was found.

CONCLUSIONS

The findings show ESD to be effective for colorectal epithelial neoplasm, making it possible to resect the whole lesion in one piece and to provide precise histologic information.

Endoscopic submucosal dissection for locally recurrent colorectal lesions after previous endoscopic mucosal resection

PURPOSE

The objective of this study was to determine the efficacy and safety of endoscopic submucosal dissection for locally recurrent colorectal cancer after previous endoscopic mucosal resection.

METHODS

A total of 16 patients with locally recurrent colorectal lesions were enrolled. A needle knife, an insulated-tip knife and a hook knife were used to resect the lesion along the submucosa. The rate of the curative resection, procedure time, and incidence of complications were evaluated.

RESULTS

Of 16 lesions, 15 were completely resected with endoscopic submucosal dissection, yielding an en bloc resection rate of 93.8 percent. Histologic examination confirmed that lateral and basal margins were cancer-free in 14 patients (87.5 percent). The average procedure time was 87.2 +/- 60.7 minutes. None of the patients had immediate or delayed bleeding during or after endoscopic submucosal dissection. Perforation in one patient (6.3 percent) was the only complication and was managed conservatively. The mean follow-up period was 15.5 +/- 6.8 months; none of the patients experienced lesion residue or recurrence.

CONCLUSIONS

Endoscopic submucosal dissection appears to be effective for locally recurrent colorectal cancer after previous endoscopic mucosal resection, making it possible to resect whole lesions and provide precise histologic information.

Colorectal endoscopic submucosal dissection: present status and future perspective, including its differentiation from endoscopic mucosal resection

Endoscopic submucosal dissection (ESD) allows en bloc resection of a lesion, irrespective of the size of the lesion. ESD has been established as a standard method for the endoscopic ablation of malignant tumors in the upper gastrointestinal (GI) tract in Japan. Although the use of ESD for colorectal lesions has been studied via clinical research, ESD is not yet established as a standard therapeutic method for colorectal lesions because colorectal carcinoma has unique pathological, organ specific characteristics that differ radically from those of the esophagus and stomach, and scope handling and control is more difficult in the colorectum than in the upper GI tract. Depending on the efficacy of endoscopic mucosal resection (EMR) and the clinicopathological characteristics of the colorectal tumor, the proposed indications for colorectal ESD are as follows: (1) lesions difficult to remove en bloc with a snare EMR, such as nongranular laterally spreading tumors (particularly the pseudo depressed type), lesions showing a type VI: pit pattern, and large lesions of the protruded type suspected to be carcinoma; (2) lesions with fibrosis due to biopsy or peristasis; (3) sporadic localized lesions in chronic inflammation such as ulcerative colitis; and (4) local residual carcinoma after EMR. Colorectal ESD is currently in the development stage, and a standard protocol will be available in the near future. We hope that colorectal tumors will be efficiently treated by a treatment method appropriately selected from among EMR, ESD, and surgical resection after precise preoperative diagnosis based on techniques such as magnifying colonoscopy.

Increased expression of beta-catenin, phosphorylated glycogen synthase kinase 3beta, cyclin D1, and c-myc in laterally spreading colorectal tumors

Laterally spreading tumors (LSTs) are considered a special subtype of superficial colorectal tumor. This study was performed to characterize the clinicopathological features and examine activation of the Wnt/beta-catenin pathway in LSTs and protruded-type colorectal adenomas (PAs). Fifty LSTs and 54 PAs were collected, and their clinicopathological characteristics were compared. The expression of E-cadherin, beta-catenin, glycogen synthase kinase-3beta (GSK-3beta), phosphorylated GSK-3beta, (phospho-GSK-3beta), cyclin D1, and c-myc was investigated by immunohistochemical staining on serial sections. Patients with LSTs were significantly older than those bearing PAs (63.4 vs 47.4 years old; p<0.001). The mean size of LSTs was significantly larger than that of PAs (27.0 mm vs 14.6 mm; p<0.01). Forty-eight percent of LSTs were located in the proximal colon, which was significantly higher than that of PAs (18.5%; p<0.05). Expression of beta-catenin, phospho-GSK-3beta, cyclin D1, and c-myc was significantly increased in LSTs compared with PAs (p<0.05). However, E-cadherin and total GSK-3beta expression was not significantly different between the two groups. The level of beta-catenin expression correlated strongly with phospho-GSK-3beta, cyclin D1, and c-myc expression in LSTs but not in PAs. Our findings suggest that activation of the Wnt/beta-catenin pathway is more prevalent in LSTs than in PAs, suggesting that phosphorylation-dependent inactivation of GSK-3beta may be involved in LST carcinogenesis.

Perspective on the practical indications of endoscopic submucosal dissection of gastrointestinal neoplasms

Endoscopic submucosal dissection (ESD) is a new endoluminal therapeutic technique involving the use of cutting devices to permit a larger resection of the tissue over the muscularis propria. The major advantages of the technique in comparison with polypectomy and endoscopic mucosal resection are controllable resection size and shape and en bloc resection of a large lesion or a lesion with ulcerative findings. This technique is applied for the endoscopic treatment of epithelial neoplasms in the gastrointestinal tract from the pharynx to the rectum. Furthermore, some carcinoids and submucosal tumors in the gastrointestinal tract are treated by ESD. To determine the indication, two aspects should be considered. The first is a little likelihood of lymph node metastasis and the second is the technical resectability. In this review, practical guidelines of ESD for the gastrointestinal neoplasms are discussed based on the evidence found in the literature.

A case of advanced colonic cancer that developed from residual laterally spreading tumor treated by piecemeal endoscopic mucosal resection

This case report showed a laterally spreading tumor treated by endoscopic mucosal resection that developed as an advanced colon cancer. A 74-year-old female was visited to treat a colon tumor that was pointed out at another hospital. Total colonoscopy revealed a laterally spreading tumor (LST) 25 mm in diameter in the cecum. The lesion was diagnosed as homogenous granular type LST (G-type LST) and treated by endoscopic piecemeal mucosal resection in January 2004. A tumor was recognized by follow-up endoscopic examination in April 2006. The scar of endoscopic piecemeal mucosal resection had developed to advanced colon cancer and was treated by laparoscopy-associated ileocecal resection with D3 lymph node resection. Previous reports indicated that G-type LST in the colon could be treated by piecemeal resection, but this report suggests that G-type LST resected by piecemeal endoscopic mucosal resection might develop to advanced colon cancer.

Screening for Rectal Cancer – Will it Improve Cure Rates?

Here we give an overview of colorectal cancer screening strategies with an emphasis on the diagnosis and management of rectal cancer. We review the published studies on screening in the high-risk population, including patients with a history of colorectal cancer, inflammatory bowel disease and inherited conditions. In the average-risk population, the evidence base for a number of screening strategies is evaluated, including endoscopy, contrast studies and faecal occult blood testing. Screening guidelines in the high-risk population are predominantly based on case-control studies comparing the incidence of colorectal cancer in screened and control groups. Screening the average-risk population for colorectal cancer reduces cancer-specific mortality by 15% after biennial guaiac faecal occult blood testing and 50-80% after flexible sigmoidoscopy. All of the screening strategies outlined have a greater sensitivity for distal lesions than proximal lesions.