Predictors of complete endoscopic mucosal resection of flat and depressed gastrointestinal neoplasia of the colon

Risk factors of unintentional piecemeal resection in endoscopic mucosal resection for colorectal polyps ≥ 10 mm

This study aimed to investigate the lesion and endoscopist factors associated with unintentional endoscopic piecemeal mucosal resection (uniEPMR) of colorectal lesions ≥ 10 mm. uniEPMR was defined from the medical record as anything other than a preoperatively planned EPMR. Factors leading to uniEPMR were identified by retrospective univariate and multivariate analyses of lesions ≥ 10 mm (adenoma including sessile serrated lesion and carcinoma) that were treated with endoscopic mucosal resection (EMR) at three hospitals. Additionally, a questionnaire survey was conducted to determine the number of cases treated by each endoscopist. A learning curve (LC) was created for each lesion size based on the number of experienced cases and the percentage of uniEPMR. Of 2557 lesions, 327 lesions underwent uniEPMR. The recurrence rate of uniEPMR was 2.8%. Multivariate analysis showed that lesion diameter ≥ 30 mm (odds ratio 11.83, 95% confidence interval 6.80-20.60, p < 0.0001) was the most associated risk factor leading to uniEPMR. In the LC analysis, the proportion of uniEPMR decreased for lesion sizes of 10-19 mm until 160 cases. The proportion of uniEPMR decreased with the number of experienced cases in the 20-29 mm range, while there was no correlation between the number of experienced cases and the proportion of uniEPMR ≥ 30 mm. These results suggest that 160 cases seem to be the minimum number of cases needed to be proficient in en bloc EMR. Additionally, while lesion sizes of 10-29 mm are considered suitable for EMR, lesion sizes ≥ 30 mm are not applicable for en bloc EMR from the perspective of both lesion and endoscopist factors.

Does completing advanced endoscopy fellowship improve outcomes after endoscopic mucosal resection?

BACKGROUND

It was reported that about 60% of the physicians in the USA believed that their Gastroenterology fellowship poorly prepared them for large polyp resection. The aim of this study was to compare endoscopic mucosal resection (EMR) efficacy and complication rates between skilled general gastroenterologists who perform high volume of EMR and advanced endoscopists.

METHODS

We identified 140 patients with documented large colonic polyps treated by 4 providers using EMR technique at Carilion Clinic, in Roanoke, Virginia, USA between 01/01/2014-12/31/2017, with follow-up through 10-2018. Information on demographics, clinical and pathological features of high-risk polyps (i.e., size, histology, site, and degree of dysplasia), timing of surveillance endoscopies, tools used during resection, and skills of performing endoscopist's were extracted. The cumulative risks of polyp recurrence after first resection using EMR technique were estimated using Kaplan-Meier curves.

RESULTS

One hundred and forty patients were identified (mean age, 64.1±11.2 years; 47.1% males). Fifty-five polyps (39.3%) were removed by 2 skilled gastroenterologists and 85 (60.7%) were removed by advanced endoscopists. Most of the polyps resected were located in the right colon (63.6%) and roughly half of the polyps were removed in piecemeal fashion. At follow-up endoscopy, the advanced endoscopy group had lower polyp recurrence rates. The median recurrence after polypectomy was significantly different between the groups (0.88 and 1.03 years for skilled gastroenterologists who did not complete and completed EMR hands-on workshops; respectively vs. 3.99 years for the advanced endoscopist who did not complete EMR hands-on workshop, P=0.03).

CONCLUSIONS

There is a need for additional EMR training since polyp recurrence was significantly different between the groups despite high rates of piecemeal resection in the advanced endoscopy groups.

Anchoring endoscopic mucosal resection versus conventional endoscopic mucosal resection for large nonpedunculated colorectal polyps: a randomized controlled trial

BACKGROUND : Colorectal polyps > 10 mm in size are often incompletely resected. Anchoring-endoscopic mucosal resection (A-EMR) is the technique of making a small incision at the oral side of the polyp using a snare tip after submucosal injection to avoid slippage during ensnaring. This study was performed to evaluate whether A-EMR could increase the complete resection rate for large colorectal polyps compared with conventional endoscopic mucosal resection (C-EMR). METHODS : Polyps with sizes of 10-25 mm were randomly allocated to either the A-EMR or the C-EMR groups. RESULTS : 105 and 106 polyps were resected using A-EMR and C-EMR, respectively. In the intention-to-treat population, the complete resection rate was 89.5 % in the A-EMR group and 74.5 % in the C-EMR group (relative risk [RR] 1.20, 95 %CI 1.04 to 1.38; P = 0.01). The en bloc resection rates for the A-EMR and C-EMR groups were 92.4 % vs. 76.4 % (RR 1.21, 95 %CI 1.06 to 1.37; P = 0.005) and R0 resection rates were 77.1 % vs. 64.2 % (RR 1.18, 95 %CI 0.98 to 1.42; P = 0.07), respectively. The median (interquartile range [IQR]) total procedure time was 3.2 (2.6-4.1) minutes in the A-EMR group and 3.0 (2.2-4.6) minutes in the C-EMR group (median difference 0.2 minutes, 95 %CI -0.22 to 0.73; P = 0.25). There was one episode of delayed bleeding and one perforation in the C-EMR group. CONCLUSIONS : A-EMR was superior to C-EMR for the complete resection of large colorectal polyps. A-EMR can be considered one of the standard methods for the removal of colorectal polyps of 10 mm or more in size.

Cap-assisted EMR versus standard inject and cut EMR for treatment of large colonic laterally spreading tumors: a randomized multicenter study (with videos)

BACKGROUND AND AIMS

Piecemeal EMR of colorectal laterally spreading tumors (LSTs) >20 mm is effective. Experience is limited in the use of cap-assisted EMR (EMR-C) for resection of colonic lesions. We compared the efficacy and the safety of EMR-C for the removal of colonic LSTs ≥30 mm with "inject-and-cut" standard EMR (EMR-S).

METHODS

In this randomized trial from 4 Italian centers, 138 patients were treated with EMR-C and 102 with EMR-S. The rates of residual lesions, percentage of recurrence after 12 months, and adverse events were evaluated.

RESULTS

One hundred forty-three lesions were resected with EMR-C and 102 with EMR-S. Argon plasma coagulation (APC) was used as adjunctive treatment in 2.9% of EMR-Cs and in 22.5% of EMR-Ss (P < .001). The median time required was 20 minutes for EMR-C and 30 minutes for EMR-S (P < .001). Adverse events (AEs) occurred in 14 EMR-Cs (10.1%; 2 perforations, 11 bleeding events, and 1 stenosis) and in 22 EMR-Ss (21.6%; 1 perforation and 21 bleeding events) (P = .017). Intraprocedural AEs occurred in 3.6% of EMR-Cs and 16.7% of EMR-Ss (P = .001). Overall, residual lesions within 12 months were found to be significantly higher with EMR-S (32 patients, 31.4%) than with EMR-C (8 patients, 5.8%) (P < .001). Recurrence at follow-up colonoscopy in 12 months occurred in 7 EMR-Cs (5.1%) and 17 EMR-Ss (16.7%; P < .001).

CONCLUSIONS

The study demonstrated the feasibility and safety of EMR-C for removing large colorectal LSTs, with higher eradication rates, shorter resection time, and less use of APC when compared with EMR-S. (Clinical trial registration number: NCT03498664.).

Post-EMR for colorectal polyps, thermal ablation of defects reduces adenoma recurrence: A meta-analysis

Background and study aims  Adenoma recurrence is one of the key limitations of endoscopic mucosal resection (EMR), which occurs in 15 % to 30 % of cases during first surveillance colonoscopy. The main hypothesis behind adenoma recurrence is leftover micro-adenomas at the margins of post-EMR defects. In this systematic review and meta-analysis, we evaluated the efficacy of snare tip soft coagulation (STSC) at the margins of mucosal defects to reduce adenoma recurrence and bleeding complications. Methods  Electronic databases such as PubMed and the Cochrane library were used for systematic literature search. Studies with polyps only resected by piecemeal EMR and active treatment: with STSC, comparator: non-STSC were included. A random effects model was used to calculate the summary of risk ratio and 95 % confidence intervals. The main outcome of the study was to compare the effect of STSC versus non-STSC with respect to adenoma recurrence at first surveillance colonoscopy after thermal ablation of post-EMR defects. Results  Five studies were included in the systematic review and meta-analysis. The total number patients who completed first surveillance colonoscopy (SC1) in the STSC group was 534 and in the non-STSC group was 514. The pooled adenoma recurrence rate was 6 % (37 of 534 cases) in the STSC arm and 22 % (115 of 514 cases) in the non-STSC arm, (odds ratio [OR] 0.26, 95 % confidence interval [CI], 0.16-0.41, P  = 0.001). The pooled delayed post-EMR bleeding rate 19 % (67 of 343) in the STSC arm and 22 % (78 of 341) in the non-STSC arm (OR 0.82, 95 %CI, 0.57-1.18). Conclusions  Thermal ablation of post-EMR defects significantly reduces adenoma recurrence at first surveillance colonoscopy.

Underwater vs Conventional Endoscopic Mucosal Resection of Large Sessile or Flat Colorectal Polyps: A Prospective Randomized Controlled Trial

BACKGROUND & AIMS

Conventional endoscopic mucosal resection (CEMR) with submucosal injection is the current standard for the resection of large, nonmalignant colorectal polyps. We investigated whether underwater endoscopic mucosal resection (UEMR) is superior to CEMR for large (20-40mm) sessile or flat colorectal polyps.

METHODS

In this prospective randomized controlled study, patients with sessile or flat colorectal polyps between 20 and 40 mm in size were randomly assigned to UEMR or CEMR. The primary outcome was the recurrence rate after 6 months. Secondary outcomes included en bloc and R0 resection rates, number of resected pieces, procedure time, and adverse events.

RESULTS

En bloc resection rates were 33.3% in the UEMR group and 18.4% in the CEMR group (P = .045); R0 resection rates were 32.1% and 15.8% for UEMR vs CEMR, respectively (P = .025). UEMR was performed with significantly fewer pieces compared to CEMR (2 pieces: 45.5% UEMR vs 17.7% CEMR; P = .001). The overall recurrence rate did not differ between both groups (P = .253); however, subgroup analysis showed a significant difference in favor of UEMR for lesions of >30 mm to ≤40 mm in size (P = .031). The resection time was significantly shorter in the UEMR group (8 vs 14 minutes; P < .001). Adverse events did not differ between both groups (P = .611).

CONCLUSIONS

UEMR is superior to CEMR regarding en bloc resection, R0 resection, and procedure time for large colorectal lesions and shows significantly lower recurrence rates for lesions >30 mm to ≤40 mm in size. UEMR should be considered for the endoscopic resection of large colorectal polyps.

Evaluation of complete cold forceps polypectomy resection rate for 3- to 5-mm colorectal polyps

BACKGROUND AND STUDY AIMS

The propriety of cold forceps polypectomy (CFP) using jumbo biopsy forceps for diminutive polyps remains controversial. We conducted a prospective study to evaluate the complete CFP resection rate of 3-5-mm polyps using additional endoscopic mucosal resection (EMR) specimens following CFP.

PATIENTS AND METHODS

Patients with 3-5-mm protruded or flat elevated colorectal polyps diagnosed endoscopically as adenomas or serrated lesions were prospectively enrolled. CFP using jumbo biopsy forceps was used to remove the eligible polyps and repeated until the absence of residuals were confirmed via image-enhanced endoscopy or chromoendoscopy. After CFP, saline was injected at the defect, and the marginal specimen of the defect was resected using EMR to histologically evaluate the residue. The primary outcome was the complete CFP resection rate, which was defined as no residue at the EMR site. Other outcomes were the number of CFP bites and the complete resection rate by lesion size.

RESULTS

Eighty patients with 120 polyps were enrolled. The mean polyp size was 4.1 ± 0.7 mm. The overall complete resection rate was 96.7% (95% confidence interval [CI], 91.7-98.7), and the rates for 3-, 4- and 5-mm polyps were 100% (95% CI, 86.7-100), 96.0% (95% CI, 86.5-98.9) and 95.5% (95% CI, 85.1-98.8), respectively. The one-bite CFP rates were 92%, 60% and 31% for the 3-, 4- and 5-mm polyps, respectively.

CONCLUSIONS

The complete CFP resection rate for 3-5-mm polyps was acceptable, although the one-bite clearance rate decreased as the polyp size increased (UMIN000028841).

Tip-in Endoscopic Mucosal Resection for 15- to 25-mm Colorectal Adenomas: A Single-Center, Randomized Controlled Trial (STAR Trial)

INTRODUCTION

One-piece endoscopic mucosal resection (EMR) for lesions >15 mm is still unsatisfactory, and attempted 1-piece EMR for lesions >25 mm can increase perforation risk. Therefore, modifications to ensure 1-piece EMR of 15- to 25-mm lesions would be beneficial. The aim of this study was to investigate whether Tip-in EMR, which anchors the snare tip within the submucosal layer, increases en bloc resection for 15- to 25-mm colorectal lesions compared with EMR.

METHODS

In this prospective randomized controlled trial, patients with nonpolypoid colorectal neoplasms of 15-25 mm in size were recruited and randomly assigned in a 1:1 ratio to undergo Tip-in EMR or standard EMR, stratified by age, sex, tumor size category, and tumor location. The primary endpoint was the odds ratio of en bloc resection adjusted by location and size category. Adverse events and procedure time were also evaluated.

RESULTS

We analyzed 41 lesions in the Tip-in EMR group and 41 lesions in the EMR group. En bloc resection was achieved in 37 (90.2%) patients undergoing Tip-in EMR and 30 (73.1%) who had EMR. The adjusted odds ratio of en bloc resection in Tip-in EMR vs EMR was 3.46 (95% confidence interval: 1.06-13.6, P = 0.040). The Tip-in EMR and EMR groups did not differ significantly in adverse event rates (0% vs 4.8%) or median procedure times (7 vs 5 minutes).

DISCUSSION

In this single-center randomized controlled trial, we found that Tip-in EMR significantly improved the en bloc resection rate for nonpolypoid lesions 15-25 mm in size, with no increase in adverse events or procedure time.

Continuous warfarin administration versus heparin bridging therapy in post colorectal polypectomy haemorrhage: a study protocol for a multicentre randomised controlled trial (WHICH study)

Background

Endoscopic removal of colorectal adenoma is considered an effective treatment for reducing the mortality rates associated with colorectal cancer. Warfarin, a type of anticoagulant, is widely used for the treatment and prevention of thromboembolism; however, bleeding may increase with its administration after polypectomy. In recent times, a high incidence of bleeding after endoscopic polypectomy has been reported in patients receiving heparin bridge therapy. However, previous studies have not compared the bleeding rate after endoscopic colorectal polypectomy between patients who continued with anticoagulant therapy and those who received heparin bridge therapy. We hypothesised that endoscopic colorectal polypectomy under the novel treatment with continuous warfarin is not inferior to endoscopic colorectal polypectomy under standard treatment with heparin bridge therapy with respect to the rate of postoperative bleeding. This study aims to compare the efficacy of endoscopic colorectal polypectomy with continuous warfarin administration and endoscopic colorectal polypectomy with heparin bridge therapy with respect to the rate of postoperative bleeding.

Methods

We will conduct a prospective multicentre randomised controlled non-inferiority trial of two parallel groups. We will compare patients scheduled to undergo colorectal polypectomy under anticoagulant therapy with warfarin. There will be 2 groups, namely, a standard treatment group (heparin bridge therapy) and the experimental treatment group (continued anticoagulant therapy). The primary outcome measure is the rate of postoperative bleeding. On the contrary, the secondary outcomes include the rate of cumulative bleeding, rate of overt haemorrhage (that does not qualify for the definition of haemorrhage after endoscopic polypectomy), incidence of haemorrhage requiring haemostasis during endoscopic polypectomy, intraoperative bleeding during endoscopic colorectal polypectomy requiring angiography, abdominal surgery and/or blood transfusion, total rate of bleeding, risk factors for postoperative bleeding, length of hospital stay, incidence of thromboembolism, prothrombin time-international ratio (PT-INR) 28 days after the surgery, and incidence of serious adverse events.

Discussion

The results of this randomised controlled trial will provide valuable information for the standardisation of management of anticoagulants in patients scheduled to undergo colorectal polypectomy.

Trial registration

UMIN-CTR UMIN000023720. Registered on 22 August 2016

Cap-fitted endoscopic mucosal resection of ≥ 20 mm colon flat lesions followed by argon plasma coagulation results in a low adenoma recurrence rate

Background and study aims  Endoscopic mucosal resection (EMR) is increasingly used for the treatment of large colonic polyps (≥ 20 mm). A drawback of EMR is local adenoma recurrence. Therefore, we studied the impact of argon plasma coagulation (APC) of the EMR edge on local adenoma recurrence. Patients and methods  This was a retrospective study of patients with laterally spreading tumors (LST) ≥ 20 mm, who underwent EMR from January 2009 to August 2018 and follow-up endoscopic assessment. A cap-fitted endoscope was used to assess completeness of resection by systematically inspecting the EMR defect for any macroscopic disease. This was followed by forced APC of the resection edge followed by clip closure of the defect. Surveillance colonoscopy was performed at 6 months after resection to detect recurrence. Results  Two hundred forty-six patients met the inclusion criteria. Most were female (53 %) and white (80 %), with a Median age of 64 years. Median polyp size was 35 mm (interquartile range, 30-45 mm). Most polyps were located in the right colon (77 %) and were removed by piecemeal EMR (70 %). Eleven patients (5 %) had residual tumor at the resection site. Conclusions  We observed low adenoma recurrence after argon plasma coagulation of the EMR edge with a cap fitted colonoscope in patients with LST ≥ 20 mm of the colon, which requires further validation in a randomized controlled study.

Clinical outcomes of submucosal colorectal cancer diagnosed after endoscopic resection: a focus on the need for surgery

Background/Aims

We aimed to investigate the proportion of and risk factors for residual cancer and/or lymph node metastasis after surgery was performed because of high-risk pathological features in endoscopic resection specimen of suspected superficial submucosal colorectal cancer (SSMC).

Methods

We reviewed medical records of 497 patients (58.8 ± 9.8 years, 331 males) undergoing endoscopic resection of suspected SSMC. High-risk pathological features included: deep submucosal cancer invasion ≥ 1,000 μm; positive lymphovascular and/or perineural invasion; poorly differentiated adenocarcinoma; and positive resection margin. We investigated the occurrence of additional surgery and residual cancer and/or lymph node involvement in the surgical specimen.

Results

En bloc resection was performed in 447 patients (89.9%). High-risk pathological features were detected in 372 patients (74.8%). Additional surgery was performed in 336 of 372 patients with high-risk pathological features. Of these, 47 surgical specimens (14.0%) showed residual cancer and/or lymph node metastasis. Piecemeal resection was more common in those with residual cancer and/or lymph node involvement than those without (9/47 [19.1%] vs. 24/289 [8.3%], P= 0.032). Positive resection margin was also significantly associated with positive residual cancer and/or lymph node involvement. As the number of high-risk pathological features increased, the risk of regional lymph node metastasis increased proportionally (P= 0.002).

Conclusions

High-risk pathological features were frequently detected after endoscopic resection of suspected SSMC while residual cancer and/or lymph node metastasis were not commonly present in the additional surgical specimen. Further optimized strategy for proper endoscopic management of suspected SSMC is necessary.

Prophylactic Snare Tip Soft Coagulation and Its Impact on Adenoma Recurrence After Colonic Endoscopic Mucosal Resection

BACKGROUND

Up to 20% of patients can have recurrence of adenomatous tissue at first surveillance study after colon endoscopic mucosal resection of large polyps.

AIMS

To determine whether an educational intervention discussing thermal ablation of lateral margins of the mucosectomy site of post-endoscopic mucosal resection defect with snare tip soft coagulation (STSC) would decrease adenoma recurrence.

METHODS

We performed a single-center quality improvement project from November 1, 2016, to November 30, 2017. Gastroenterologists underwent an educational intervention demonstrating the treatment of peripheral margins of mucosectomy site with STSC after standard mucosectomy technique. These cases (intervention group) were compared with consecutive procedures performed prior to commencement of the quality improvement study (pre-intervention group). Patients with large colorectal lesions (≥ 20 mm) were included.

RESULTS

Of the 120 patients here included, overall demographics of the groups were similar and the most common histology was sessile serrated adenoma (study group 45% vs 32% control group). Adenoma recurrence on intervention group and pre-intervention group was 12% versus 30%; p = 0.01. On univariate analysis, biopsy prior to mucosectomy, intraprocedural bleeding, and application of STSC on mucosectomy defect were the strongest predictors of adenoma recurrence. Adenoma recurrence in the intervention group was significantly lower than in the pre-intervention group in both univariate (odds ratio, 0.3 [95% CI, 0.11-0.80]) and multivariate analyses (odds ratio, 0.2 [95% CI, 0.12-0.92]).

CONCLUSIONS

The implementation of STSC of post-endoscopic mucosal resection peripheral defects is clinically feasible and significantly decreased adenoma recurrence.

Long-term outcomes of endoscopically resected laterally spreading tumors with a positive histological lateral margin

BACKGROUND

With advances in diagnostic endoscopy, the incidence of superficial colorectal tumors, including laterally spreading tumors (LSTs), has increased. However, little is known about the long-term results of LSTs with positive lateral margin after endoscopic treatment. This study aimed to evaluate the long-term clinical outcomes and risk factors for local recurrence of LSTs with positive lateral margin after initial endoscopic resection.

METHODS

We performed a retrospective analysis of the medical records of 324 patients who had 363 LSTs with positive lateral margin after endoscopic resection at a tertiary academic medical center. The medical records from 2011 to 2015 were analyzed. Local recurrence was confirmed through endoscopic finding and subsequent biopsy analysis. We assessed the local recurrence rate and performed multivariate analyses to identify the factors associated with local recurrence.

RESULTS

Follow-up colonoscopy was performed in 176 of 363 LSTs. The local recurrence rate was 6.3% (11/176), with a median (interquartile range [IQR]) follow-up period of 19.8 (12.4-46.5) months. In multivariate analysis, local recurrence was associated with piecemeal resection (odds ratio [OR] 6.62, 95% confidence interval [CI] 1.28-34.33; p = 0.024) and inversely associated with thermal ablation (OR 0.033, 95% CI 0.00-0.45; p = 0.011). At surveillance colonoscopy, histology of the recurrent tumor was adenoma in 10 (90.9%) of 11; these were treated endoscopically.

CONCLUSIONS

In this retrospective study, we found that endoscopically resected LSTs with positive lateral margin have a low recurrence rate. Piecemeal resection was associated with higher local recurrence, and thermal ablation was inversely associated with local recurrence. Endoscopic resection with positive lateral margin combined with thermal ablation leads to a low recurrence rate.

Underwater Endoscopic Mucosal Resection

Although an established standard, conventional endoscopic mucosal resection (EMR) has disseminated despite an absence of studies demonstrating the value of submucosal injection. Several consequences of poorly executed submucosal injection may increase the difficulty and risk of EMR. Underwater EMR (UEMR), an alternative resection method for colonic neoplasms, avoids the need for submucosal injections. In comparison with reported outcomes of EMR, UEMR achieves similar rates of complete resection with comparable safety, with lower rates of recurrence and fewer repeat procedures. UEMR also compares favorably with endoscopic submucosal dissection in terms of procedure time and rates of complete resection, recurrence, and complications.

Risk factors for incomplete polyp resection after cold snare polypectomy

BACKGROUND

Incomplete polyp resection (IPR) is recognized as a risk factor for interval colorectal cancer (ICC), and is, therefore, an important issue in polypectomy. Cold snare polypectomy (CSP) is a procedure that does not involve electrocautery and has no burn effect. Therefore, there is the possibility that the risk of ICC associated with IPR is higher in cases undergoing CSP than in those undergoing hot polypectomy. However, little is known about the risk factors for IPR after CSP.

PURPOSE

Precise identification of the risk factors can lead to prevention of IPR after CSP. Therefore, we performed this observational study for accurate identification of the risk factors for IPR after CSP.

METHODS

Medical records of a total of 501 patients with 1177 colorectal polyps that were resected at Omori Red Cross Hospital between October 2017 and March 2018 were retrospectively reviewed. The lateral and deep margins of the resected polyps were evaluated to check for the resection completeness.

RESULTS

Among the 1177 polyp resections, 1163 were included in the final analysis. IPR was detected in 206 (17.7%) cases. Performance of the resection by a trainee (OR (95% CI) 1.87 (1.328-2.632); P < 0.001) was identified as an independent risk factor for IPR in patients undergoing CSP.

CONCLUSIONS

Performance of the polypectomy by a trainee was identified as a significant risk factor for IPR in patients undergoing CSP. Prospective, randomized studies are necessary in the future to develop effective methods for the prevention/control of IPR after CSP.

Novel technique for endoscopic en bloc resection (EMR+) - Evaluation in a porcine model

BACKGROUND

Endoscopic en bloc resection of larger polyps is relevant because risk of advanced neoplasia or malignancy correlates with tumor size. Recurrence rates after piecemeal endoscopic mucosal resection (EMR) are high and endoscopic submucosal dissection (ESD) is associated with higher complication rates in the western world.

AIM

To develop a modified endoscopic en bloc resection technique using an external additional working channel and novel agent for submucosal injection.

METHODS

EMR+ was considered as modified grasp and snare technique. For simultaneous use of a grasping and cutting device a novel additional working channel was used (AWC^®, Ovesco Endoscopy, Tübingen, Germany). AWC^® is installed on the outer surface of the endoscope, covered with a plastic sleeve and designed for single use. For submucosal injection a new agent consisting of poloxamers was used (LiftUp^®, Ovesco Endoscopy, Tübingen, Germany). The agent is liquid at room temperature and forms a stable and permanent gel cushion after injection. Safety of LiftUp^® has been shown in a pre-clinical study in domestic pigs. LiftUp^® is commercially not yet available but approval is expected in early 2019. EMR+ was first developed ex vivo (explanted pig stomach) and subsequently evaluated in vivo (stomach, porcine model, 3 domestic pigs). Main outcome measurements were: Procedure time, macroscopic en bloc resection and adverse events.

RESULTS

Concept of EMR+ was first developed ex vivo (explanted pig stomach). Ex vivo, 22 resections were performed after technique was established. Median procedure time (measured from begin of injection to extraction of resection specimen) was 7 min (range 5-11, SD 1.68) and median size of resection specimens was 30 mm × 26 mm × 11 mm ex vivo. Subsequently 13 resections were performed in vivo (stomach, porcine model, 3 domestic pigs). In vivo, median procedure time (measured from begin of injection to extraction of resection specimen) was 5 min (range 3-12, SD 2.72) and median size of resection specimens was 35 mm × 35 mm × 11 mm. In vivo, resection was macroscopic complete in 92.3%, major adverse events were not observed. In one case (7.7%) minor periprocedural bleeding was observed and managed by coagulation.

CONCLUSION

EMR+ appeared to be effective and safe and was easy and fast to perform in the porcine model. EMR+ needs to be further evaluated clinically in comparative trials.

Risk factors for local recurrence and appropriate surveillance interval after endoscopic resection

BACKGROUND

Risk factors for local recurrence after polypectomy, endoscopic mucosal resection (EMR), and endoscopic submucosal dissection (ESD) have not been identified. Additionally, the appropriate interval for endoscopic surveillance of colorectal tumors at high-risk of local recurrence has not been established.

AIM

To clarify the clinicopathological characteristics of recurrent lesions after endoscopic colorectal tumor resection and determine the appropriate interval.

METHODS

Three hundred and sixty patients (1412 colorectal tumors) who underwent polypectomy, EMR, or ESD and received endoscopic surveillance subsequently for more than one year to detect local recurrence were enrolled in this study. The clinicopathological factors associated with local recurrence were determined via univariate and multivariate analyses.

RESULTS

Local recurrence was observed in 31 of 360 (8.6%) patients [31 of 1412 (2.2%) lesions] after colorectal tumor resection. Piecemeal resection, tumor size of more than 2 cm, and the presence of villous components were associated with colorectal tumor recurrence after endoscopic resection. Of these three factors, the piecemeal resection procedure was identified as an independent risk factor for recurrence. Colorectal tumors resected into more than five pieces were associated with a high risk of recurrence since the average period from resection to recurrence in these cases was approximately 3 mo. The period to recurrence in cases resected into more than 5 pieces was much shorter than that in those resected into less than 4 pieces (3.8 ± 1.9 mo vs 7.9 ± 5.0 mo, P < 0.05).

CONCLUSION

Local recurrence of endoscopically treated colorectal tumors depends upon the outcome of first endoscopic procedure. Piecemeal resection was the only significant risk factor associated with local recurrence after endoscopic resection.

Incidence and risk factors of advanced neoplasia after endoscopic mucosal resection of colonic laterally spreading lesions

PURPOSE

To investigate advanced neoplasia (AN) after endoscopic mucosal resection (EMR) of colonic laterally spreading lesions (LSLs).

METHODS

A retrospective study of patients who underwent injection-assisted EMR of colonic LSLs ≥ 10 mm was performed. Primary outcome was overall rate of AN at initial surveillance colonoscopy. Secondary outcomes were the rates of residual AN (rAN) at the EMR site and metachronous AN (mAN), and analysis of risk factors for AN, including effect of surveillance guidance.

RESULTS

Three hundred seventy-four patients underwent successful EMR for 388 LSLs. AN occurred in 66/374 (17.6%) patients on initial surveillance colonoscopy at median follow-up of 364.5 days. Two patients had both rAN and mAN, for a total of 68 instances of AN, including 30/374 (8.0%) cases of rAN and 38/374 (10.2%) cases of mAN. On multivariate analysis, use of piecemeal resection was associated with increased likelihood of residual AN (P = 0.003, OR 9.2, 95% CI 2.1-33.3). Twenty-nine out of thirty cases (96.7%) of rAN were successfully endoscopically managed at surveillance colonoscopy.

CONCLUSIONS

AN occurred in 17.6% of all patients at initial surveillance colonoscopy at a median of 1 year after EMR. Roughly half of the instances of AN were metachronous lesions. Our data support a 1-year surveillance interval after EMR of LSLs ≥ 10 mm with careful inspection of the entire colon, not just the prior resection site.

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.

Adenoma recurrence after endoscopic mucosal resection: propensity score analysis of old and new colonoscopes and Sydney recurrence tool implementation

BACKGROUND AND STUDY AIMS

 Risk factors for colorectal adenoma recurrence after endoscopic mucosal resection (EMR) have been well documented. We assessed the efficacy of the newer 190 colonoscope versus the standard 180 colonoscope for complete resection of lateral spreading lesions.

PATIENTS AND METHODS

 A single-center, retrospective study of patients who underwent EMR with Olympus 180 or 190 colonoscopes from January 1, 2010 to September 30, 2016. We included patients with lesions ≥ 20 mm and surveillance colonoscopy (SC1) after index EMR. A propensity score approach with inverse probability weighting was used to control for potential confounders. A secondary aim was to identify risk factors for recurrence and assess the applicability of the Sydney EMR recurrence tool (SERT) by grading each lesion of our cohort and analyzing associations with recurrence.

RESULTS

 Two hundred ninety-one lesions met inclusion criteria for the study. Odds ratio (OR) for recurrence with the 190 colonoscope was 1.06 ( P  = .85). Adenoma size ( P  = .02) and use of argon plasma coagulation (APC; P  < .001) were risk factors for recurrence. Lesions with SERT scores > 0 had a higher recurrence risk during follow-up (32 % vs 21 %; OR 1.71; P  = .05). Lesions with SERT scores = 0 reached a plateau for recurrence at 12 and 18 months in Kaplan-Meier curves.

CONCLUSIONS

 The use of 190 colonoscopes did not measurably affect adenoma recurrence at SC1. Recurrence was associated with adenoma size, complementary APC for resection, and SERT scores > 0. Lesions with SERT scores = 0 that remain negative for recurrence at 18 months may return to routine surveillance.

Local recurrence and subsequent endoscopic treatment after endoscopic piecemeal mucosal resection with or without precutting in the colorectum

Background/Aims

Precutting before endoscopic piecemeal mucosal resection (EPMR) may increase colorectal polyp resection effectiveness. We aimed to identify risk factors for recurrence after conventional EPMR (CEPMR) and precut EPMR (PEPMR) and investigated endoscopic treatment outcomes for recurrent cases.

Methods

The medical records of patients with colorectal polyps treated by EPMR were analyzed. Patients without follow-up surveillance colonoscopies were excluded.

Results

Among 359 lesions, the local recurrence rate on the first surveillance colonoscopy was 5.8% (18/312) and 6.4% (3/47) after CEPMR and PEPMR, respectively. Among lesions without recurrence at the first surveillance colonoscopy, the rates of late recurrence on subsequent surveillance colonoscopy were 3.9% (6/152) and 0% after CEPMR and PEPMR, respectively. Larger tumor size was the only independent risk factor for recurrence (odds ratio, 7.93; 95% confidence interval, 1.95–32.30; P<0.001). Endoscopic treatment was performed for all 27 recurrences. A combination of ≥2 endoscopic treatment modalities was used in 19 of 27 recurrences (70.4%). Surveillance colonoscopies were performed in 20 of 27 recurrences after endoscopic treatment. One (5.0%) had a re-recurrence and was treated by surgical resection because recurrence occurred at the appendiceal orifice. Nineteen of 20 lesions (95.0%) could be cured endoscopically, although 3 of the 19 showed second or third recurrences and were treated by repeat endoscopic resection.

Conclusions

The local recurrence rates after CEPMR and PEPMR were similar. Larger tumor size was an independent risk factor for local recurrence after EPMR. Endoscopic treatment of recurrences resulted in high cure rates, although combination methods were necessary in many cases.

Colorectal endoscopic mucosal resection (EMR)

Colonoscopy has the benefit of detecting and treating precancerous adenomatous polyps and thus reduces mortality associated with CRC. Screening colonoscopy is the keystone for prevention of colorectal cancer. Over the last 20 years there has been increased in the management of large colorectal polyps from surgery to endoscopic removal techniques which is less invasive. Traditionally surgical resection was the treatment of choice for many years for larger polyps but colectomy poses significant morbidity of 14-46% and mortality of up to 7%. There are several advantages of endoscopic resection technique over surgery; it is less invasive, less expensive, has rapid recovery, and preserves the normal gut functions. In addition patient satisfaction and efficacy of EMR is higher with minor complications. Thus, this has facilitated the development of advanced resection technique for the treatment of large colorectal polyps called as endoscopic mucosal resection (EMR).

Clinical utility of the SMSA grading tool for the management of colonic neoplastic lesions

BACKGROUND

Whilst polyp size has been traditionally used as a predictor of the complexity of endoscopic resection, the influence of other factors is increasingly recognised. The SMSA grading system takes into account polyp Site, Morphology, Size and Access, with higher scores correlating with increased technical difficulty.

AIMS

To evaluate whether the SMSA grading tool correlates with endoscopic and clinical outcomes.

METHODS

This retrospective study was conducted at two high volume centres in the United Kingdom and Italy. All polyps identified at colonoscopy were included in this study and classified as per the SMSA grading system.

RESULTS

A total of 1668 lesions were resected in 1016 patients. There was a positive correlation between increasing SMSA level and the inability to resect lesions "en bloc" (p<0.001). Histologically complete clearance was higher in the lower SMSA groups (p<0.0001). Additional endoscopic therapies, were more commonly required with the higher SMSA groups to achieve histological clearance (p<0.0001). Moreover, advanced histology in resection specimens and procedural complications were significantly less common in SMSA level 1 lesions compared to level 3 or 4 lesions (p<0.0001).

CONCLUSIONS

The SMSA grading tool is a useful predictor of outcome following the resection of colonic neoplastic lesions.

Detecting colorectal cancer using electrical impedance spectroscopy: an ex vivo feasibility study

OBJECTIVE

Colorectal cancer is the fourth most common cancer worldwide, with a lifetime risk of around 20%. Current techniques do not allow clinicians to objectively assess tissue abnormality during endoscopy and perioperatively. A method capable of objectively assessing samples in real time and which can be included in minimally invasive diagnostic and management strategies would be highly transformative. Electrical impedance spectroscopy (EIS) may provide such a solution. This paper presents a feasibility study on using EIS in assessing colorectal tissue.

APPROACH

We performed tetrapolar EIS using ZedScan on excised human colorectal tumour tissue and the matched normal colonic mucosa in 22 freshly resected specimens following elective surgery for colorectal cancer. Histopathological examination was used to confirm the final diagnosis. Statistical significance was assessed using the Wilcoxon signed rank test.

MAIN RESULTS

Tetrapolar EIS could discriminate cancer with statistically significant results when applying frequencies between 305 Hz and 625 kHz (p  <  0.05). 300 Ω was set as the transfer impedance threshold to detect cancer. Thus, the area under the corresponding receiver operating characteristic curve for this threshold was 0.7105.

SIGNIFICANCE

This feasibility study demonstrates that impedance spectra changes in colorectal cancer tissue are detectable and may be statistically significant, suggesting that EIS has the potential to be the core technology in a novel non-invasive point of care test for detecting colorectal cancer. These results warrant further development by increasing the size of the study with a device specifically designed for colorectal cancer.

Pocket-creation method facilitates endoscopic submucosal dissection of colorectal laterally spreading tumors, non-granular type

Background and study aims The pocket-creation method (PCM) is a novel strategy for endoscopic submucosal dissection (ESD). The aim of this study is to determine the efficacy of the PCM for colorectal laterally spreading tumors, non-granular type (LST-NG). Patients and methods The records of 126 consecutive patients with colorectal LST-NG who underwent ESD between April 2012 and July 2015 were retrospectively reviewed. Patients were divided into PCM (n = 73) and conventional method (CM) (n = 53) groups. Results The en bloc resection rate in the PCM group was significantly higher than in the CM group (100 % [73/73] vs. 92 % [49/53], P = 0.03). The en bloc resection rate with severe fibrosis was higher in the PCM group than in the CM group (100 % [3/3] vs. 60 % [3/5]). The R0 resection rate for the two groups was not statistically significantly different (93 % [68/73] vs. 91 % [48/53], P = 0.74). The perforation rate in the PCM group was lower than in the CM group although not statistically significantly less (0 % 0/73 vs. 4 % 2/53, P = 0.18). For lesions resected en bloc, dissection speed for the PCM group was significantly faster than for the CM group (median [IQR], 19 [13 -24] vs. 14 [10 - 22] mm²/min, P = 0.03). Conclusion ESD using PCM achieves a reliable and safe resection of colorectal LST-NG.

Safety of endoscopic mucosal resection (EMR) of large non-pedunculated colorectal adenomas in the elderly

BACKGROUND

Endoscopic mucosal resection (EMR) has been proven to be safe and effective for the treatment of colorectal adenomas. However, data are limited on the safety of this technique for large polyps and in elderly patients. Aims of our study were to examine the bleeding and perforation rates in patients with large non-pedunculated adenomas (≥20mm) and to evaluate the influence of size (≥40mm) and age (≥75 years) on the complication rates.

METHODS

In this multicenter retrospective study, patients who underwent EMR of non-pedunculated adenomas ≥20mm between January 2012 and March 2016 were included. The demographics of the patients, the use of antithrombotic drugs, size of the polyps, type of resection, pathology report, occurrence of post-polypectomy bleeding, and perforation- and recurrence rate were collected.

RESULTS

In 343 patients, 412 adenomas were removed. Eighty patients (23.3%) were ≥75 years of age, 138 polyps (33.5%) were ≥40mm. Bleeding complications were observed in 28 cases (6.8%) and were found significantly more frequent in adenomas ≥40mm, independent of the use of antithrombotic therapy. Five perforations (1.2%) were described, not related to the size of the polyp. There was no significant difference in complication rates between patients <75 years and patients ≥75 years. Bleeding complications rates were significantly higher in patients receiving double antithrombotic therapy.

CONCLUSION

EMR is safe in elderly patients. EMR of adenomas of ≥40mm was associated with more bleeding complications. Future studies should address how the bleeding rates can be reduced in these patients, especially in those who use double antithrombotic treatment.

Endoscopic Management of Large (≥2 cm) Non-pedunculated Colorectal Polyps: Impact of Polyp Morphology on Outcomes

BACKGROUND AND AIMS

Referrals for endoscopic management of large non-pedunculated (NP) colorectal polyps have increased as new techniques have emerged. The outcomes for referred large NP polyps based on the polyp morphology were investigated METHODS: A retrospective review of patients referred for large (≥20 mm) NP polyp management from January 2010 through June 2014 was completed. Polyp morphology was classified as either a NP polyp with depression (M1) or NP polyp with no depression (M0). Differences in treatment, histology, adverse events, outcomes at follow-up including residual disease, and need for surgical treatment were determined by morphology for all NP polyps ≥20 mm in size.

RESULTS

One-hundred and sixty-nine M1 and 136 M0 polyps ≥20 mm were removed endoscopically during the review period. Mean size was 31.9 ± 11.0 mm in M1, and 26.8 ± 9.5 mm in M0 group (p < 0.0001). En bloc resection was possible in 18.3 % of M1 and 30.9 % of M0 lesions (p = 0.011) with endoscopic submucosal dissection used in 13 and 2.2 % of polyps, respectively (p < 0.0001). Residual polyp was found in 26.5 % (27/102) of M1 and 13.6 % (12/88) of M0 patients at surveillance colonoscopy (p = 0.029). On multivariate analysis, piecemeal resection and M1 morphology showed significant association with residual polyp (OR 4.23, 95 % CI 1.23-14.59, p = 0.022, and OR 2.15, 95 % CI 1.004-4.62, p = 0.049, respectively).

CONCLUSION

Effective endoscopic management of large NP colorectal polyps, especially polyps without depression (M0), can be accomplished in the great majority of patients. Polyp morphology, particularly the presence or absence of depression, is a useful tool which influenced treatment, histology, and outcomes.

Surveillance after endoscopic and surgical resection of colorectal cancer

With the increase in colorectal cancer burden, surveillance following endoscopic and surgical resection is an essential issue. The aim of surveillance programs is improvement of patient survival by early detection of residual tumor tissue or local recurrence, metachronous colorectal tumors, and metastases. Appropriate surveillance should be determined according to this risk of factors. In current guidelines, only surveillance colonoscopy is recommended after endoscopic resection of polyps with high-grade dysplasia, whereas intensive, multimodality surveillance using colonoscopy, radiological imaging and tumor marker measurements is recommended following surgical resection of invasive colorectal cancer. Detailed recommendations, including the timing of surveillance, are described based on high-quality evidence. However, there are still many unresolved issues for which more high-quality evidence is required.

Endoscopic mucosal resection: learning curve for large nonpolypoid colorectal neoplasia

BACKGROUND AND AIMS

Colorectal EMR for nonpolypoid neoplasia achieves better outcomes when performed by expert endoscopists. The time point at which the endoscopist achieves expert level remains to be defined. The objective of this study was to establish a learning curve of colorectal EMR for nonpolypoid neoplasia based on residual tissue on surveillance colonoscopy and adverse event rate.

METHODS

Five hundred seventy-eight consecutive patients underwent EMR of colorectal neoplasia by 1 of 3 primary endoscopists between December 2004 and September 2013 in a tertiary academic center. Primary analyses focused on the largest lesion for patients with more than 1 lesion (median age, 69 years; median polyp size, 30 mm; 51% en bloc resection). Data on surveillance colonoscopy were available for 74%. Learning curves were calculated for each of the 3 main outcome measurements: the presence of residual neoplasia on surveillance colonoscopy, endoscopic assessment of incomplete EMR, and the occurrence of an immediate bleeding adverse event.

RESULTS

Residual neoplasia on surveillance colonoscopy was present for 23.2% of patients, the rate of endoscopist-assessed incomplete EMR was 27.6%, and immediate bleeding adverse events occurred in 6.9% of patients. Although there was between-endoscopist variability, the overall rates of residual neoplasia and incomplete EMR decreased to below 20% to 25% after 100 EMRs; initial decreases in both rates were observed for earlier EMRs. Immediate bleeding adverse events occurred at a low frequency for each endoscopist across all EMRs. Perforation requiring surgical intervention occurred in 1 patient (0.2%).

CONCLUSIONS

This study demonstrated that an unexpectedly high number of 100 colorectal EMR procedures for large nonpolypoid colorectal neoplasia are required to achieve a plateau phase for crucial outcomes.

Evaluation and long-term outcomes of the different modalities used in colonic endoscopic mucosal resection

Endoscopic mucosal resection (EMR) has been used in western countries to remove colonic polyps for at least the last two decades. Significant experience has been accumulated and the efficacy of the method has recently been evaluated in a large meta-analysis. A number of variations to modify the technique, including knife-assisted, cap-assisted, ligation devices, and underwater EMR, have been developed in an attempt to improve outcomes. However, to date there are only limited data comparing these techniques or demonstrating the superiority of any one of them. This article reviews the current evidence on the efficacy of each of these modified techniques.

Update on Difficult Polypectomy Techniques

Endoscopists often encounter colon polyps that are technically difficult to resect. These lesions traditionally were managed surgically, with significant potential morbidity and mortality. Recent advances in endoscopic techniques and instruments have allowed endoscopists to safely and effectively remove colorectal lesions with high technical and clinical success and potentially avoid invasive surgery. Endoscopic mucosal resection (EMR) has gained acceptance as the first-line therapy for large colorectal lesions. Endoscopic submucosal dissection (ESD) has been reported to be associated with higher rate of en bloc resection and less risk of short-time recurrence, but with an increased risk of adverse events. Therefore, the role of colorectal ESD should be restricted to lesions with high-risk morphologic features of submucosal invasion. In this article, we review the recent literature on the endoscopic management of difficult colorectal neoplasms.

Outcome of EMR as an alternative to surgery in patients with complex colon polyps

BACKGROUND AND AIMS

Patients with complex colon polyps were traditionally referred for surgery to avoid adverse events associated with endoscopic resection. Recent advances in endoscopic imaging as well as endoscopic hemostasis and clip closure allow for the use of EMR as an alternative to surgery for such lesions. To determine the outcome of treatment of complex colon polyps with EMR as an alternative to surgery, we conducted a retrospective observational study.

METHODS

Two hundred three patients with complex colon polyps were referred to an EMR center as an alternative to surgery. Patients underwent a protocol-driven EMR. The primary endpoint was the complete resection rate. Secondary endpoints were safety, residual adenoma rate, and incidence of missed synchronous polyps.

RESULTS

EMR was performed in 155 patients and was deferred in 48 patients who were referred to surgery. EMR specimens revealed benign polyps in 149 and cancer in 6 patients. EMR adverse events occurred in 7 patients, requiring hospitalization in 5 of them. None of the patients died as a result of their adverse events. Surveillance colonoscopy at 4 to 6 months after resection of a benign lesion in 137 patients revealed residual adenoma at the scar site in 6 patients and additional synchronous precancerous lesions in 117 patients that were not removed by the referring endoscopist. None underwent surgery for failure of EMR. The overall precancerous lesion burden was 2.83 per patient, the adenoma burden was 2.13 per patient, and the serrated polyp burden was .69 per patient.

CONCLUSIONS

EMR can be used instead of surgery for complex colon polyps in 75% of patients with few adverse events and few residual adenomas at resection sites. In addition, careful repeat examination of the entire colon for synchronous lesions overlooked by the referring endoscopist is required for most patients. (

CLINICAL TRIAL REGISTRATION NUMBER

NCT01827241.).

Endoscopic mucosal resection and endoscopic submucosal dissection of large colonic polyps

Almost all large and complex colorectal polyps can now be resected endoscopically. Piecemeal endoscopic mucosal resection (PEMR) is an established technique with fairly low complication risk and good short-term and medium-term outcomes. Several modifications to the basic injection and snare technique have been developed contributing to safer and more complete resections. Delayed bleeding requiring reintervention is the most troublesome complication in 2-7% of patients, particularly in those with comorbidities and large, right-sided polyps. Endoscopic submucosal dissection (ESD) has become popular in Japan and has theoretical advantages over PEMR in providing a complete, en bloc excision for accurate histological staging and reduced local recurrence. These advantages come at the cost of a more complex, expensive and time-consuming procedure with a higher risk of perforation, particularly early in the procedure learning curve. These factors have contributed to the slow adoption of ESD in the West and the challenge to develop new devices and endoscopic platforms that will make ESD easier and safer. Currently, ESD indications are limited to large rectal lesions, in which procedural complications are easily managed, and for colorectal polyps with a high risk of containing tiny foci of early submucosally invasive cancer, whereby ESD may be curative compared with PEMR.

Regional center for complex colonoscopy: yield of neoplasia in patients with prior incomplete colonoscopy

BACKGROUND AND AIMS

Incomplete colonoscopy increases the risk of incident proximal colon cancer postcolonoscopy. Incomplete colonoscopy is often followed by barium enema or CT colonography. We sought to describe the yield of completion colonoscopy in a regional center for complex colonoscopy.

METHODS

This is a retrospective cohort study of 520 consecutive patients referred to a single colonoscopist over a 14-year period for completion colonoscopy after a previous incomplete examination.

RESULTS

Colonoscopy was completed to the cecum in 506 of 520 patients (97.3%). A total of 913 conventional adenomas was removed in 277 patients (adenoma detection rate 53.3%). There were 184 adenomas ≥ 1 cm in size or with advanced pathology. There were 525 serrated-class lesions removed in 175 patients, including 54 sessile serrated polyps in 26 patients and 41 hyperplastic polyps greater than 1 cm in 26 patients. Nine colorectal cancers were found. We estimated that approximately 57% of the conventional adenomas, 58% of the sessile serrated polyps, 27% of the hyperplastic polyps, and all 9 cancers detected by the completion colonoscopy were beyond the extent of the previous examination.

CONCLUSIONS

The yield of completion colonoscopy in a cohort of patients with previous failed cecal intubation was substantial. Regional centers for complex colonoscopy can provide high rates of cecal intubation in cases of incomplete colonoscopy and high yields of lesions in these cases. The regional center for complex colonoscopy is an important medical service.

Risk of Advanced Colorectal Neoplasia According to the Number of High-Risk Findings at Index Colonoscopy: A Korean Association for the Study of Intestinal Disease (KASID) Study

BACKGROUND

Data regarding outcomes for patients with multiple findings for high-risk adenomas are scarce.

AIM

To compare the risk for colorectal neoplasm (CRN) recurrence according to the number of high-risk findings.

METHODS

This was a retrospective and multicenter study. Patients who had one or more high-risk adenomas at the index colonoscopy and underwent follow-up colonoscopy 2.5 or more years after the index colonoscopy were included. The number of high-risk findings was defined as follows: number of adenomas larger than 1 cm + number of adenomas with HGD + number of adenomas with a villous component + existence (counted as 1) or nonexistence (counted as 0) of three or more adenomas.

RESULTS

A total of 1646 patients were included, and the mean duration between index and follow-up colonoscopy was approximately 4 years. The cumulative incidence rate of recurrent advanced CRN in patients with three or more high-risk findings was higher than that in patients with one or two high-risk findings (p < 0.001). However, the difference in 3-year cumulative incidence rates of recurrent advanced CRN between the two groups was not great, although it was statistically significant (4.8 vs. 2.3 %, p = 0.039).

CONCLUSIONS

A 3-year surveillance interval for patients with multiple high-risk findings, regardless of the number of high-risk findings, appears reasonable.

Preoperative indicators of failure of en bloc resection or perforation in colorectal endoscopic submucosal dissection: implications for lesion stratification by technical difficulties during stepwise training

BACKGROUND AND AIMS

The technical difficulties inherent in endoscopic submucosal dissection (ESD) for colorectal neoplasms may result in the failure of en bloc resection or perforation. The aim of this retrospective study was to assess the predictors of en bloc resection failure or perforation by using preoperatively available factors.

METHODS

Between September 2002 and March 2013, 716 colorectal ESDs in 673 consecutive patients were performed at a tertiary cancer center. Patient characteristics, tumor location, tumor type, colonoscopy-related factors, and endoscopist experience were assessed based on a prospectively recorded institutional ESD database. Logistic regression analysis was performed to identify predictors of failure of en bloc resection or perforations, with subgroup analyses of ESDs performed by endoscopists less experienced in colorectal ESD (<40 cases) and for colonic lesions only.

RESULTS

On multivariate analysis, independent predictors of failure of en bloc resection or perforations were the presence of fold convergence (odds ratio [OR] 4.4; 95% confidence interval [95% CI], 1.9-9.9), protruding type (OR 3.6; 95% CI, 1.8-7.1), poor endoscope operability (OR 3.5; 95% CI, 1.8-6.9), right-sided colonic lesions (OR 3.0; 95% CI, 1.5-6.3 vs rectal lesions), left-sided colonic lesions (OR 3.2; 95% CI, 1.7-6.3, vs rectal lesions), the presence of an underlying semilunar fold (OR 2.1; 95% CI, 1.3-3.6), and a less-experienced endoscopist (OR 2.1; 95% CI, 1.3-3.6). Among less-experienced endoscopists, colonic lesions were independent predictors (right-sided colonic lesions 8.1; 95% CI, 2.9-25.1; left-sided colonic lesions 8.1; 95% CI, 2.5-28.3 vs rectal lesions). For colonic lesions, the presence of fold convergence (OR 3.7; 95% CI, 1.6-8.6), poor endoscope operability (OR 3.6; 95% CI, 1.8-7.2), a less-experienced endoscopist (OR 3.0; 95% CI, 1.7-1.8), and the presence of an underlying semilunar fold (OR 2.7; 95% CI, 1.5-4.7) were identified predictors.

CONCLUSION

This study successfully identified predictors of en bloc resection failure or perforation. Understanding these indicators could help to accurately stratify lesions according to technical difficulty and to appropriately select endoscopists.

Outcome and risk of recurrence for endoscopic resection of colonic superficial neoplastic lesions over 2 cm in diameter

BACKGROUND

Large colorectal superficial neoplastic lesions are challenging to remove. This study aimed to assess the outcomes of routine endoscopic resection of large (≥2 cm and <3 cm) and giant (≥3 cm) lesions.

METHODS

From 4587 endoscopic resections, 265 (5.7%) large and giant lesions were removed in 249 patients. We retrospectively analyzed 125 patients (141 endoscopic mucosal resection, 73 large and 68 giant lesions) with a follow-up of 6-12 months. Rate of en bloc and piecemeal resection, recurrence and risk factors were analyzed.

RESULTS

En bloc was performed in 92 cases (65.2%) and piecemeal resection in 49 (34.8%). A complete endoscopic resection was achieved in 139 cases (98.5%) with radical resection in 84/139 cases (60.4%). Argon plasma coagulation was applied in 18/141 lesions (12.8%). A recurrence occurred in 16/139 lesions (11.5%). The risk of recurrence at one year was significantly higher for giant than large lesions (p=0.03). The recurrence risk was higher in treated than in non-argon plasma coagulation treated lesions (p=0.01).

CONCLUSIONS

endoscopic mucosal resection is a safe and effective routine treatment for large superficial neoplastic lesions. The risk factors for recurrence include giant size, non-protruding morphology, piecemeal technique and argon plasma coagulation.

Endoscopic mucosal resection of colorectal adenomas > 20 mm: Risk factors for recurrence

AIM: To evaluate risk factors for local recurrence after endoscopic mucosal resection of colorectal adenomas > 20 mm.

METHODS: Retrospective data analysis of 216 endoscopic mucosal resections for colorectal adenomas > 20 mm in 179 patients (40.3% female; median age 68 years; range 35-91 years). All patients had at least 1 follow-up endoscopy with a minimum control interval of 2 mo (mean follow-up 6 mo/2.0-43.4 mo). Possible factors associated with local recurrence were analyzed by univariate and multivariate analysis.

RESULTS: Median size of the lesions was 30 mm (20-70 mm), 69.0% were localized in the right-sided (cecum, ascending and transverse) colon. Most of the lesions (85.6%) showed a non-pedunculated morphology and the majority of resections was in piecemeal technique (78.7%). Histology showed carcinoma or high-grade intraepithelial neoplasia in 51/216 (23.6%) lesions including 4 low risk carcinomas (pT1a, L0, V0, R0 - G1/G2). Histologically proven recurrence was observed in 33/216 patients (15.3%). Patient age > 65 years, polyp size > 30 mm, non-pedunculated morphology, localization in the right-sided colon, piecemeal resection and tubular-villous histology were found as associated factors in univariate analysis. On multivariate analysis, only localization in the right-sided colon (HR = 6.842/95%CI: 1.540-30.394; P = 0.011), tubular-villous histology (HR = 3.713/95%CI: 1.617-8.528; P = 0.002) and polyp size > 30 mm (HR = 2.563/95%CI: 1.179-5.570; P = 0.017) were significantly associated risk factors for adenoma recurrence.

CONCLUSION: Meticulous endoscopic follow-up is warranted after endoscopic mucosal resection of adenomas localized in the right-sided colon larger than > 30 mm, with tubular-villous histology.

British Society of Gastroenterology/Association of Coloproctologists of Great Britain and Ireland guidelines for the management of large non-pedunculated colorectal polyps

These guidelines provide an evidence-based framework for the management of patients with large non-pedunculated colorectal polyps (LNPCPs), in addition to identifying key performance indicators (KPIs) that permit the audit of quality outcomes. These are areas not previously covered by British Society of Gastroenterology (BSG) Guidelines.A National Institute of Health and Care Excellence (NICE) compliant BSG guideline development process was used throughout and the Appraisal of Guidelines for Research and Evaluation (AGREE II) tool was used to structure the guideline development process. A systematic review of literature was conducted for English language articles up to May 2014 concerning the assessment and management of LNPCPs. Quality of evaluated studies was assessed using the Scottish Intercollegiate Guidelines Network (SIGN) Methodology Checklist System. Proposed recommendation statements were evaluated by each member of the Guideline Development Group (GDG) on a scale from 1 (strongly agree) to 5 (strongly disagree) with >80% agreement required for consensus to be reached. Where consensus was not reached a modified Delphi process was used to re-evaluate and modify proposed statements until consensus was reached or the statement discarded. A round table meeting was subsequently held to finalise recommendations and to evaluate the strength of evidence discussed. The GRADE tool was used to assess the strength of evidence and strength of recommendation for finalised statements.KPIs, a training framework and potential research questions for the management of LNPCPs were also developed. It is hoped that these guidelines will improve the assessment and management of LNPCPs.

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.

Protective association of colonoscopy against proximal and distal colon cancer and patterns in interval cancer

BACKGROUND

The protective effect of colonoscopy against proximal colorectal cancer is variable and depends on the detection and complete removal of precancerous polyps.

OBJECTIVE

To estimate the efficacy of colonoscopy in a medical center with open-access screening colonoscopy since 1998.

DESIGN

Nested case-control study with incidence density sampling.

SETTING

University-affiliated Veterans Affairs Medical Center.

PATIENTS

Colorectal cancer (CRC) cases and control subjects selected from screening age patients matched by age, gender, and date of first primary care visit.

MAIN OUTCOME MEASUREMENT

Colonoscopy preceding the CRC diagnosis date.

RESULTS

A total of 20.2% of CRC cases had a colonoscopy in the preceding 10 years compared with 49.0% of control subjects (adjusted odds ratio [aOR], 0.20; 95% confidence interval [CI], 0.11-0.34). Colonoscopy was strongly associated with decreased odds of both distal CRC (aOR, 0.16; 95% CI, 0.07-0.34) and proximal CRC (aOR, 0.26; 95% CI, 0.11-0.58). The fraction of cases attributed to interval cancers was 10.5%. Missed lesions predominantly localized to the cecum and rectum, and recurrent lesions clustered in the hepatic flexure. Cecal intubation rate was 93% (98% in adequately prepped patients), and the adenoma detection rate was 45.2% in the control group.

LIMITATIONS

Single-center, retrospective case-control design.

CONCLUSION

In an open access colonoscopy program characterized by a high cecal intubation rate and adenoma detection rate, colonoscopy was strongly associated with reduced odds of both distal and proximal CRC. Among interval cancers, missed lesions clustered in the cecum and rectum and recurrent lesions in the hepatic flexure.

Complete resection of colorectal adenomas: what are the important factors in fellow training?

BACKGROUND

The complete removal of adenomatous polyps is important for reducing interval cancer after colonoscopy.

AIMS

To identify factors affecting the completeness of colonoscopic polypectomies and to evaluate the experience level of fellows who achieve competence compared with that of experts.

METHODS

Medical records of 1,860 patients who underwent at least one polypectomy for an adenomatous polyp at Seoul National University Hospital between March 2011 and February 2013 were retrospectively reviewed. A total of 3,469 adenomatous polyps were included. The lateral and deep margins of the resected polyps were evaluated to check the resection completeness.

RESULTS

Of the 3,469 adenomatous polyps, 1,389 (40.0 %) were removed by two experts and 2,080 (60.0 %) were removed by seven fellows. In the expert-treated group, larger size [odds ratio (OR) 2.81 for ≥20 mm, 95 % confidence interval (CI) 1.64-4.84, P < 0.001] and right-sided location (OR 1.31, 95 % CI 1.05-1.63, P = 0.019) were associated with incomplete resection. In the fellow-treated group, not only polyp characteristics [right-sided location (OR 1.41, 95 % CI 1.18-1.69, P < 0.001)], but also the cumulative number of procedures was also related to resection completeness. After 300 polypectomies, the complete resection rate of the fellows was comparable to that of the experts.

CONCLUSIONS

In the fellow-treated group, the level of procedure experience was closely associated with the polypectomy outcomes. Meticulous attention is critical to ensure the completeness of polypectomies performed by trainee endoscopists during the training program.

JGES guidelines for colorectal endoscopic submucosal dissection/endoscopic mucosal resection

Colorectal endoscopic submucosal dissection (ESD) has become common in recent years. Suitable lesions for endoscopic treatment include not only early colorectal carcinomas but also many types of precarcinomatous adenomas. It is important to establish practical guidelines in which the preoperative diagnosis of colorectal neoplasia and the selection of endoscopic treatment procedures are properly outlined, and to ensure that the actual endoscopic treatment is useful and safe in general hospitals when carried out in accordance with the guidelines. In cooperation with the Japanese Society for Cancer of the Colon and Rectum, the Japanese Society of Coloproctology, and the Japanese Society of Gastroenterology, the Japan Gastroenterological Endoscopy Society has recently compiled a set of colorectal ESD/endoscopic mucosal resection (EMR) guidelines using evidence-based methods. The guidelines focus on the diagnostic and therapeutic strategies and caveat before, during, and after ESD/EMR and, in this regard, exclude the specific procedures, types and proper use of instruments, devices, and drugs. Although eight areas, ranging from indication to pathology, were originally planned for inclusion in these guidelines, evidence was scarce in each area. Therefore, grades of recommendation were determined largely through expert consensus in these areas.

Local recurrence after endoscopic resection for large colorectal neoplasia: a multicenter prospective study in Japan

OBJECTIVES

Conventional endoscopic resection (CER) is a widely accepted treatment for early colorectal neoplasia; however, large colorectal neoplasias remain problematic, as they necessitate piecemeal resection, increasing the risk of local recurrence. Endoscopic submucosal dissection (ESD) can improve the en bloc resection rate. This study aimed to evaluate local recurrence and its associated risk factors after endoscopic resection (ER) for colorectal neoplasias ≥20 mm.

METHODS

A multicenter prospective study at 18 medium- and high-volume specialized institutions was conducted in Japan. Follow-up colonoscopy was performed after 12 months in cases of complete resection and after 3-6 months in cases of incomplete resection. Local recurrence was confirmed by endoscopic findings and/or pathological analysis.

RESULTS

Follow-up colonoscopy was performed in 1,524 of 1,845 enrolled colorectal neoplasias (mean age, 65 years; 885 men; median tumor size, 32.8 mm). The local recurrence rates were 4.3% (65/1,524), 6.8% (55/808), and 1.4% (10/716) for the entire cohort, for CER, and for ESD, respectively. The relative risks of local recurrence were 0.21 (95% confidence interval, 0.11-0.39) with ESD compared with CER, 0.32 (95% confidence interval, 0.11-0.92) with en bloc ESD compared with en bloc CER, and 0.90 (95% confidence interval, 0.39-2.12) with piecemeal ESD compared with piecemeal CER. Significant factors associated with local recurrence were piecemeal resection, laterally spreading tumors of granular type, tumor size ≥40 mm, no pre-treatment magnification, and ≤10 years of experience in CER, and piecemeal resection only in ESD.

CONCLUSIONS

En bloc ESD reduces the local recurrence rate for large colorectal neoplasias. Piecemeal resection is the most important risk factor for local recurrence regardless of the ER method used.

Novel risk stratification for recurrence after endoscopic resection of advanced colorectal adenoma

BACKGROUND

Advanced colorectal adenoma (ACA) refers to adenomas with the following predictive characteristics: ≥1 cm in diameter, and/or villous component, and/or high-grade dysplasia. ACA has high risk of transforming to colorectal cancer, and the recurrence rate is relatively high.

OBJECTIVE

To assess the outcomes of patients with ACA undergoing endoscopic resection and to identify risk factors for local recurrence and development of metachronous advanced neoplasm.

DESIGN

Retrospective cohort study.

SETTING

Tertiary care medical center.

PATIENTS

From 2005 to 2011, the records of 3625 patients who underwent colonoscopic polypectomy at Seoul National University Hospital were retrospectively reviewed. Patients with synchronous colorectal cancers, inflammatory bowel disease, previous colorectal resection, loss to follow-up, and incomplete resection were excluded.

INTERVENTION

Endoscopic resection for ACA.

MAIN OUTCOME MEASUREMENTS

Local recurrence and metachronous advanced neoplasm.

RESULTS

The study included 917 patients with 1206 ACAs. The median duration of follow-up was 28.5 months (interquartile range, 12.8-51.7). Independent risk factors for local recurrence included ACA with 2 or more predictive characteristics (adjusted hazard ratio [HR], 2.46; 95% confidence interval [CI], 1.11-5.48; P = .027) and piecemeal resection (adjusted HR, 6.96; 95% CI, 1.58-30.71; P = .010). Independent risk factors for metachronous advanced neoplasm were male gender (adjusted HR, 1.65; 95% CI, 1.02-2.65; P = .041), ≥3 adenomas (adjusted HR, 2.56; 95% CI, 1.72-3.82; P < .001), and ≥3 ACAs (adjusted HR, 1.44; 95% CI, 1.01-2.06; P = .045).

LIMITATIONS

Retrospective design.

CONCLUSION

ACAs with 2 or more predictive characteristics recurred locally at a higher rate than ACAs with 1 predictive characteristic. These results suggest that patients who are found to have ACAs with 2 or more predictive factors at index colonoscopy are at higher risk for local recurrence, and follow-up colonoscopy should be performed sooner.