Why attempt en bloc resection of non-pedunculated colorectal adenomas? A systematic review of the prevalence of superficial submucosal invasive cancer after endoscopic submucosal dissection

Limited wedge resection for T1 colon cancer (LIMERIC-II trial) - rationale and study protocol of a prospective multicenter clinical trial

BACKGROUND

The sole presence of deep submucosal invasion is shown to be associated with a limited risk of lymph node metastasis. This justifies a local excision of suspected deep submucosal invasive colon carcinomas (T1 CCs) as a first step treatment strategy. Recently Colonoscopy-Assisted Laparoscopic Wedge Resection (CAL-WR) has been shown to be able to resect pT1 CRCs with a high R0 resection rate, but the long term outcomes are lacking. The aim of this study is to evaluate the safety, effectiveness and long-term oncological outcomes of CAL-WR as primary treatment for patients with suspected superficial and also deeply-invasive T1 CCs.

METHODS

In this prospective multicenter clinical trial, patients with a macroscopic and/or histologically suspected T1 CCs will receive CAL-WR as primary treatment in order to prevent unnecessary major surgery for low-risk T1 CCs. To make a CAL-WR technically feasible, the tumor may not include > 50% of the circumference and has to be localized at least 25 cm proximal from the anus. Also, there should be sufficient distance to the ileocecal valve to place a linear stapler. Before inclusion, all eligible patients will be assessed by an expert panel to confirm suspicion of T1 CC, estimate invasion depth and subsequent advise which local resection techniques are possible for removal of the lesion. The primary outcome of this study is the proportion of patients with pT1 CC that is curatively treated with CAL-WR only and in whom thus organ-preservation could be achieved. Secondary outcomes are 1) CAL-WR's technical success and R0 resection rate for T1 CC, 2) procedure-related morbidity and mortality, 3) 5-year overall and disease free survival, 4) 3-year metastasis free survival, 5) procedure-related costs and 6) impact on quality of life. A sample size of 143 patients was calculated.

DISCUSSION

CAL-WR is a full-thickness local resection technique that could also be effective in removing pT1 colon cancer. With the lack of current endoscopic local resection techniques for > 15 mm pT1 CCs with deep submucosal invasion, CAL-WR could fill the gap between endoscopy and major oncologic surgery. The present study is the first to provide insight in the long-term oncological outcomes of CAL-WR.

TRIAL REGISTRATION

CCMO register (ToetsingOnline), NL81497.075.22, protocol version 2.3 (October 2022).

Endoscopic management of colorectal polyps

Colorectal polyps are premalignant lesions in the lower gastrointestinal tract. Endoscopic polypectomy is an effective strategy to prevent colorectal cancer morbidity and more invasive procedures. Techniques for the endoscopic resection of polyps keep evolving, and endoscopists are required to perform the most appropriate technique for each polyp. In this review, we outline the evaluation and classification of polyps, update the recommendations for optimal treatment, describe the polypectomy procedures and their strengths/weaknesses, and discuss the promising innovative methods or concepts.

Colonoscopy-Assisted Laparoscopic Wedge Resection for the Treatment of Suspected T1 Colon Cancer

BACKGROUND

Local en bloc resection of pT1 colon cancer has been gaining acceptance during the last few years. In the absence of histological risk factors, the risk of lymph-node metastases (LNM) is negligible and does not outweigh the morbidity and mortality of an oncologic resection. Colonoscopy-assisted laparoscopic wedge resection (CAL-WR) has proved to be an effective and safe technique for removing complex benign polyps. The role of CAL-WR for the primary resection of suspected T1 colon cancer has to be established.

METHODS

This retrospective study aimed to determine the radicality and safety of CAL-WR as a local en bloc resection technique for a suspected T1 colon cancer. Therefore, the study identified patients in whom high-grade dysplasia or a T1 colon carcinoma was suspected based on histology and/or macroscopic assessment, requiring an en bloc resection.

RESULTS

The study analyzed 57 patients who underwent CAL-WR for a suspected macroscopic polyp or polyps with biopsy-proven high-grade dysplasia or T1 colon carcinoma. For 27 of these 57 patients, a pT1 colon carcinoma was diagnosed at pathologic examination after CAL-WR. Histological risk factors for LNM were present in three cases, and 70% showed deep submucosal invasion (Sm2/Sm3). For patients with pT1 colon carcinoma, an overall R0-resection rate of 88.9% was achieved. A minor complication was noted in one patient (1.8%).

CONCLUSIONS

The CAL-WR procedure is an effective and safe technique for suspected high-grade dysplasia or T1-colon carcinoma. It may fill the gap for tumors that are macroscopic suspected for deep submucosal invasion, providing more patients an organ-preserving treatment option.

A Rectum-Specific Selective Resection Algorithm Optimizes Oncologic Outcomes for Large Nonpedunculated Rectal Polyps

BACKGROUND AND AIMS

Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are complementary techniques for large (≥20 mm) nonpedunculated rectal polyps (LNPRPs). A mechanism for appropriate technique selection has not been described.

METHODS

We evaluated the performance of a selective resection algorithm (SRA) (August 2017 to April 2021) compared with a universal EMR algorithm (UEA) (July 2008 to July 2017) for LNPRPs within a prospective observational study. In the SRA, LNPRPs with features of superficial submucosal invasive cancer (SMIC) (<1000 μm; Kudo pit pattern Vi), or with an increased risk of SMIC (Paris 0-Is or 0-IIa+Is nongranular, 0-IIa+Is granular with a dominant nodule ≥10 mm) underwent ESD. The remaining LNPRPs underwent EMR. Algorithm performance was evaluated by SMIC identified after EMR, curative oncologic resection (R0 resection, superficial SMIC, absence of negative histologic features), technical success, adverse events, and recurrence at first surveillance colonoscopy.

RESULTS

A total of 480 LNPRPs were evaluated (290 UEA, 190 SRA). Median lesion size was 40 (interquartile range, 30-60) mm. SMIC was identified in 56 (11.7%) LNPRPs. Significant differences in SMIC after EMR (SRA 1 [1.0%] vs UEA 35 [12.1%]; P = .001) and curative oncologic resection (SRA n = 7 [33.3%] vs UEA n = 2 [5.7%]; P = .010) were identified. No significant differences in technical success or adverse events were identified (all P > .137). Among LNPRPs with SMIC amenable to curative oncologic resection and which underwent ESD, 100% (n = 7 of 7) were cured.

CONCLUSIONS

A rectum-specific SRA optimizes oncologic outcomes for LNPRPs and mitigates the risk of piecemeal resection of cancers.

Relevance of polyp size for primary endoscopic full-thickness resection of suspected T1 colorectal cancers

BACKGROUND

En bloc local excision of suspected T1 colorectal cancer (CRC) provides optimal tumor risk assessment with curative intent. Endoscopic full-thickness resection (eFTR) with an over-the-scope device has emerged as a local excision technique for T1 CRCs, but data on the upper size limit for achieving a histological complete (R0) resection are lacking. We aimed to determine the influence of polyp size on the R0 rate.

METHODS

eFTR procedures for suspected T1 CRCs performed between 2015 and 2021 were selected from the endoscopy databases of three tertiary centers. The main outcome was R0 resection, defined as tumor- and dysplasia-free margins (≥ 0.1 mm) for both the deep and lateral resection margins. Regression analysis was performed to identify risk factors for R1/Rx resection, mainly focusing on endoscopically estimated polyp size.

RESULTS

136 patients underwent eFTR for suspected T1 CRC (median size 15 mm [IQR 13-18 mm]; 83.1 % cancer). The rates of technical success and R0 resection were 87.5 % (119/136; 95 %CI 80.9 %-92.1 %) and 79.7 % (106/136; 95 %CI 72.1 %-85.7 %), respectively. Increasing polyp size was significantly associated with R1/Rx resection (risk ratio 2.35 per 5-mm increase, 95 %CI 1.80-3.07; P < 0.001). The R0 rate was 89.9 % (80/89) for polyps ≤ 15 mm, 71.4 % (25/35) for 16-20 mm, and 11.1 % (1/9) for those > 20 mm.

CONCLUSIONS

eFTR is associated with a 90 % R0 rate for T1 CRCs of ≤ 15 mm. Performing eFTR for polyps 16-20 mm should depend on access, their mobility, and the availability of alternative resection techniques. eFTR for > 20-mm polyps results in a high R1 rate and should not be recommended.

Endoscopic submucosal resection: a technique using novel devices for incision and resection of neoplastic lesions

BACKGROUND

Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are established techniques for treatment of superficial gastrointestinal neoplasia. Limitations of EMR are low en bloc resection rates for larger lesions, resulting in frequent recurrences. Major disadvantages of ESD are technical difficulty and long procedure times. We evaluated technical feasibility and safety of newly designed devices for en bloc resection of lesions measuring 20-40 mm in a technique called endoscopic submucosal resection (ESR).

METHODS

This case series included 93 lesions from different locations (11 stomach, 25 colon, 57 rectum) with a median size of 29 mm (range 10-70). ESR was performed using two novel instruments for circumferential mucosal incision and deep submucosal resection, respectively.

RESULTS

Resection by ESR was feasible in all cases. En bloc and R0 rates were insufficient when ESR was attempted without prior circumferential mucosal incision, but were 70 % and 63 %, respectively, when mucosal incision was done before application of the submucosal resection device. We observed three complications (two delayed bleedings, one microperforation) but no cases of emergency surgery or 30-day mortality.

CONCLUSIONS

Results demonstrated feasibility and excellent safety of ESR using two novel devices for en bloc resection of early gastrointestinal neoplasia. The technique offered relative technical ease and high efficacy.

A bioinformatics framework to identify the biomarkers and potential drugs for the treatment of colorectal cancer

Colorectal cancer (CRC), a common malignant tumor, is one of the main causes of death in cancer patients in the world. Therefore, it is critical to understand the molecular mechanism of CRC and identify its diagnostic and prognostic biomarkers. The purpose of this study is to reveal the genes involved in the development of CRC and to predict drug candidates that may help treat CRC through bioinformatics analyses. Two independent CRC gene expression datasets including The Cancer Genome Atlas (TCGA) database and GSE104836 were used in this study. Differentially expressed genes (DEGs) were analyzed separately on the two datasets, and intersected for further analyses. 249 drug candidates for CRC were identified according to the intersected DEGs and the Crowd Extracted Expression of Differential Signatures (CREEDS) database. In addition, hub genes were analyzed using Cytoscape according to the DEGs, and survival analysis results showed that one of the hub genes, TIMP1 was related to the prognosis of CRC patients. Thus, we further focused on drugs that could reverse the expression level of TIMP1. Eight potential drugs with documentary evidence and two new drugs that could reverse the expression of TIMP1 were found among the 249 drugs. In conclusion, we successfully identified potential biomarkers for CRC and achieved drug repurposing using bioinformatics methods. Further exploration is needed to understand the molecular mechanisms of these identified genes and drugs/small molecules in the occurrence, development and treatment of CRC.

Comparison of the morphology and histopathology of large nonpedunculated colorectal polyps in the rectum and colon: implications for endoscopic treatment

BACKGROUND AND AIMS

The risk of cancer in large nonpedunculated colorectal polyps ≥20 mm (LNPCPs) in the rectum relative to the remainder of the colon is unknown. We aimed to describe differences between rectal and colonic LNPCPs to better inform treatment decisions.

METHODS

Patients with LNPCPs referred to tertiary centers for endoscopic resection within a prospective, multicenter, observational cohort were evaluated. Data recorded were participant demographics, LNPCP location, morphology, resection modality, and histopathologic data. Multiple logistic regression analysis was used to identify those variables independently associated with rectal versus nonrectal location in the colon.

RESULTS

Patients with LNPCPs referred for endoscopic resection between July 2008 and July 2021 were included. Rectal LNPCPs (n = 618) were larger (median size, 40 mm vs 30 mm; P < .001) and more likely to be granular (79% vs 50%, P < .001) with a nodular component (53% vs 17%, P < .001) compared with nonrectal LNPCPs (n = 2787). Rectal LNPCPs were more likely to have tubulovillous histopathology (72% vs 47%, P < .001) and contain cancer (15% vs 6%, P < .001). After adjusting for the other features independently associated with location, cancer was more common in the rectum compared with the colon (odds ratio, 1.77; 95% confidence interval, 1.25-2.53).

CONCLUSIONS

This study suggests that compared with LNPCPs in the rest of the colon, rectal LNPCPs are more likely to be larger and contain more advanced pathology. These findings have implications for curative endoscopic resection techniques particularly where early cancer is present. (Clinical trial registration numbers: NCT01368289 and NCT02000141.).

Outcomes of endoscopic submucosal dissection for colorectal neoplasms: Prospective, multicenter, cohort trial

OBJECTIVES

Endoscopic mucosal resection (EMR) is the gold standard for the treatment of noninvasive large colorectal lesions, despite challenges associated with nonlifting lesions and a high rate of local recurrence. Endoscopic submucosal dissection (ESD) offers the possibility of overcoming these EMR limitations. However, a higher risk of complications and longer procedure time prevented its dissemination. As ESD now provides more stable results because of standardized techniques compared with those used earlier, this study aimed to quantify the rates of en bloc and curative resections, as well as ESD complications, in the present situation.

METHODS

A multicenter, large-scale, prospective cohort trial of ESD was conducted at 20 institutions in Japan. Consecutive patients scheduled for ESD were enrolled from February 2013 to January 2015.

RESULTS

ESD was performed for 1883 patients (1965 lesions). The mean procedure time was 80.6 min; en bloc and curative resections were achieved in 1759 (97.0%) and 1640 (90.4%) lesions, respectively, in epithelial lesions ≥20 mm. Intra- and postprocedural perforations occurred in 51 (2.6%) and 12 (0.6%) lesions, respectively, and emergency surgery for adverse events was performed in nine patients (0.5%).

CONCLUSIONS

This trial conducted after the standardization of the ESD technique throughout Japan revealed a higher curability, shorter procedure time, and lower risk of complications than those reported previously. Considering that the target lesions of ESD are more advanced than those of EMR, ESD can be a first-line treatment for large colorectal lesions with acceptable risk and procedure time. (Clinical Trial Registration: UMIN000010136).

Endoscopic submucosal dissection for superficial gastrointestinal lesions: European Society of Gastrointestinal Endoscopy (ESGE) Guideline - Update 2022

ESGE recommends that the evaluation of superficial gastrointestinal (GI) lesions should be made by an experienced endoscopist, using high definition white-light and chromoendoscopy (virtual or dye-based).ESGE does not recommend routine performance of endoscopic ultrasonography (EUS), computed tomography (CT), magnetic resonance imaging (MRI), or positron emission tomography (PET)-CT prior to endoscopic resection.ESGE recommends endoscopic submucosal dissection (ESD) as the treatment of choice for most superficial esophageal squamous cell and superficial gastric lesions.For Barrett's esophagus (BE)-associated lesions, ESGE suggests the use of ESD for lesions suspicious of submucosal invasion (Paris type 0-Is, 0-IIc), for malignant lesions > 20 mm, and for lesions in scarred/fibrotic areas.ESGE does not recommend routine use of ESD for duodenal or small-bowel lesions.ESGE suggests that ESD should be considered for en bloc resection of colorectal (but particularly rectal) lesions with suspicion of limited submucosal invasion (demarcated depressed area with irregular surface pattern or a large protruding or bulky component, particularly if the lesions are larger than 20 mm) or for lesions that otherwise cannot be completely removed by snare-based techniques.ESGE recommends that an en bloc R0 resection of a superficial GI lesion with histology no more advanced than intramucosal cancer (no more than m2 in esophageal squamous cell carcinoma), well to moderately differentiated, with no lymphovascular invasion or ulceration, should be considered a very low risk (curative) resection, and no further staging procedure or treatment is generally recommended.ESGE recommends that the following should be considered to be a low risk (curative) resection and no further treatment is generally recommended: an en bloc R0 resection of a superficial GI lesion with superficial submucosal invasion (sm1), that is well to moderately differentiated, with no lymphovascular invasion, of size ≤ 20 mm for an esophageal squamous cell carcinoma or ≤ 30 mm for a stomach lesion or of any size for a BE-related or colorectal lesion, and with no lymphovascular invasion, and no budding grade 2 or 3 for colorectal lesions.ESGE recommends that, after an endoscopically complete resection, if there is a positive horizontal margin or if resection is piecemeal, but there is no submucosal invasion and no other high risk criteria are met, this should be considered a local-risk resection and endoscopic surveillance or re-treatment is recommended rather than surgery or other additional treatment.ESGE recommends that when there is a diagnosis of lymphovascular invasion, or deeper infiltration than sm1, or positive vertical margins, or undifferentiated tumor, or, for colorectal lesions, budding grade 2 or 3, this should be considered a high risk (noncurative) resection, and complete staging and strong consideration for additional treatments should be considered on an individual basis in a multidisciplinary discussion.ESGE recommends scheduled endoscopic surveillance with high definition white-light and chromoendoscopy (virtual or dye-based) with biopsies of only the suspicious areas after a curative ESD.

Advanced Endoscopic Resection Techniques: Endoscopic Submucosal Dissection and Endoscopic Full-Thickness Resection

Endoscopic resection is first-line therapy in the management of superficial neoplasms throughout the gastrointestinal tract, as well as an increasingly viable therapeutic alternative in the resection of selected small deep lesions throughout the upper and lower gastrointestinal tract. The mainstay of therapy has traditionally been endoscopic snare polypectomy and endoscopic mucosal resection. However, recent innovative advancements in therapeutic endoscopy have provided for the ability to resect large superficial lesions and selected subepithelial lesions in en bloc and margin-negative fashion. In this review, we discuss the current state of the art in advanced endoscopic resection techniques including endoscopic submucosal dissection and endoscopic full-thickness resection.

Endoscopic full-thickness resection of T1 colorectal cancers: a retrospective analysis from a multicenter Dutch eFTR registry

BACKGROUND

Complete endoscopic resection and accurate histological evaluation for T1 colorectal cancer (CRC) are critical in determining subsequent treatment. Endoscopic full-thickness resection (eFTR) is a new treatment option for T1 CRC < 2 cm. We aimed to report clinical outcomes and short-term results.

METHODS

Consecutive eFTR procedures for T1 CRC, prospectively recorded in our national registry between November 2015 and April 2020, were retrospectively analyzed. Primary outcomes were technical success and R0 resection. Secondary outcomes were histological risk assessment, curative resection, adverse events, and short-term outcomes.

RESULTS

We included 330 procedures: 132 primary resections and 198 secondary scar resections after incomplete T1 CRC resection. Overall technical success, R0 resection, and curative resection rates were 87.0 % (95 % confidence interval [CI] 82.7 %-90.3 %), 85.6 % (95 %CI 81.2 %-89.2 %), and 60.3 % (95 %CI 54.7 %-65.7 %). Curative resection rate was 23.7 % (95 %CI 15.9 %-33.6 %) for primary resection of T1 CRC and 60.8 % (95 %CI 50.4 %-70.4 %) after excluding deep submucosal invasion as a risk factor. Risk stratification was possible in 99.3 %. The severe adverse event rate was 2.2 %. Additional oncological surgery was performed in 49/320 (15.3 %), with residual cancer in 11/49 (22.4 %). Endoscopic follow-up was available in 200/242 (82.6 %), with a median of 4 months and residual cancer in 1 (0.5 %) following an incomplete resection.

CONCLUSIONS

eFTR is relatively safe and effective for resection of small T1 CRC, both as primary and secondary treatment. eFTR can expand endoscopic treatment options for T1 CRC and could help to reduce surgical overtreatment. Future studies should focus on long-term outcomes.

Minimally Invasive Endoscopic and Surgical Management of Rectal Neoplasia

Rectal cancer demonstrates a characteristic natural history in which benign rectal neoplasia precedes malignancy. The worldwide burden of rectal cancer is significant, with rectal cancer accounting for one-third of colorectal cancer cases annually. The importance of early detection and successful management is essential in decreasing its clinical burden. Minimally invasive treatment of rectal neoplasia has evolved over the past several decades, which has led to reduced local recurrence rates and improved survival outcomes. The approach to diagnosis, staging, and selection of appropriate treatment modalities is a multidisciplinary effort combining interventional endoscopy, surgery, and radiology tools. This review examines the currently available minimally invasive endoscopic and surgical management options of rectal neoplasia.

Endoscopic Management of Complex Colorectal Polyps: Current Insights and Future Trends

Most colorectal cancers arise from adenomatous polyps and sessile serrated lesions. Screening colonoscopy and therapeutic polypectomy can potentially reduce colorectal cancer burden by early detection and removal of these polyps, thus decreasing colorectal cancer incidence and mortality. Most endoscopists are skilled in detecting and removing the vast majority of polyps endoscopically during a routine colonoscopy. Polyps can be considered “complex” based on size, location, morphology, underlying scar tissue, which are not amenable to removal by conventional endoscopic polypectomy techniques. They are technically more challenging to resect and carry an increased risk of complications. Most of these polyps were used to be managed by surgical intervention in the past. Rapid advancement in endoscopic resection techniques has led to a decreasing role of surgery in managing these complex polyps. These endoscopic resection techniques do require an expert in the field and advanced equipment to perform the procedure. In this review, we discuss various advanced endoscopic techniques for the management of complex polyps.

Endoscopic submucosal dissection: How to be more efficient?

Endoscopic submucosal dissection (ESD) allows an "en bloc" resection with safety margins (R0 resection) regardless of the size of the lesion. However, while R0 brings a real benefit for the patient, it is not considered sufficient by many experts to justify the technical difficulties and the longer procedure time compared to piecemeal mucosectomy. The aims of this review are to provide several technical and strategical tips to help you save time and become comfortable during ESD procedures. ESD is divided into several intertwined phases: injection, incision, access to the submucosae, and submucosal dissection itself. During injection there are some mistakes that should not be made: a superficial injection, or on the contrary, a too deep injection. A good needle and good injection technique are mandatory. Some techniques, such as repeated injection or prolonged lifting solution, can help maintain the lift. After this step, mucosal incision can be made, taking care to have a good margin to allow an R0 resection. Starting the mucosal incision from a small point allows calibration of the depth of the incision and then obtaining a nice incision. Trimming is also very important to widen submucosal access. Then comes the submucosal dissection itself. Strategies such as the tunnel strategy or the pocket creation method can help to facilitate dissection, but more importantly, traction systems have become unavoidable, especially in the stomach and colon. Most common complications are bleeding and perforation, and they usually can be managed endoscopically.

Management of large polyps in a colorectal cancer screening program with fecal immunochemical test: a community- and population-based observational study

Background and study aims  The aim of this study was to analyze presentation, management, and outcomes of large polyps (LPs; ≥ 20 mm) detected in a colorectal cancer (CRC) screening program using a quantitative fecal immunochemical test (FIT). Patients and methods  This was a retrospective community- and population-based observational study of all LPs detected in patients aged 50 to 74 years between 2015 and 2019 during FIT-positive colonoscopies within the screening program organized in Alsace (France). Results  Among 13,633 FIT-positive colonoscopies, 1256 LPs (8.5 % malignant and 51.8 % nonpedunculated) were detected by 102 community gastroenterologists in 1164 patients (one in 12 colonoscopies). The sensitivity of optical diagnosis of malignancy was 54 % for nonpedunculated and 27 % for pedunculated T1 CRCs. The endoscopic resection rate was 82.7 % (95 % confidence interval [CI] 80.3-84.9) for benign LPs (70.2 % [95 % CI 66.4-74.1]) nonpedunculated, 95.2 % [95 % CI 93.4-97.1] pedunculated), varying from 0 to 100 % depending on the endoscopist. It was correlated with cecal intubation (Pearson r  = 0.49, P  < 0.01) and adenoma detection rates ( r  = 0.25, P  = 0.01). Most endoscopists did not refer patients to more experienced endoscopists, and as a result, 60 % to 90 % of 183 surgeries for benign LPs were unwarranted. Endoscopic resection was curative for 4.3 % (95 % CI 0.9-12.0) of nonpedunculated and 37.8 % (95 % CI 22.5-55.2) of pedunculated T1 CRCs. Overall, 22 endoscopic submucosal dissections had to be performed to avoid one surgery. Conclusions  Compared with current recommendations, there is tremendous room for improvement in community endoscopy practices in the diagnosis and management of LPs. Detection and polypectomy competencies are correlated and highly variable among endoscopists. Endoscopic resection is curative for 83 % of benign LPs and 16 % of T1 CRCs.

Indications and outcomes of endoscopic resection for non-pedunculated colorectal lesions: A narrative review

In the last years, endoscopic techniques gained a crucial role in the treatment of colorectal flat lesions. At the same time, the importance of a reliable assessment of such lesions to predict the malignancy and the depth of invasion of the colonic wall emerged. The current unsolved dilemma about the endoscopic excision techniques concerns the necessity of a reliable submucosal invasive cancer assessment system that can stratify the risk of the post-procedural need for surgery. Accordingly, this narrative literature review aims to compare the available diagnostic strategies in predicting malignancy and to give a guide about the best techniques to employ. We performed a literature search using electronic databases (MEDLINE/PubMed, EMBASE, and Cochrane Library). We collected all articles about endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) registering the outcomes. Moreover, we analyzed all meta-analyses comparing EMR vs ESD outcomes for colorectal sessile or non-polypoid lesions of any size, preoperatively estimated as non-invasive. Seven meta-analysis studies, mainly Eastern, were included in the analysis comparing 124 studies and overall 22954 patients who underwent EMR and ESD procedures. Of these, eighty-two were retrospective, twenty-four perspective, nine case-control, and six cohorts, while three were randomized clinical trials. A total of 18118 EMR and 10379 ESD were completed for a whole of 28497 colorectal sessile or non-polypoid lesions > 5-10 mm in size. In conclusion, it is crucial to enhance the preoperative diagnostic workup, especially in deciding the most suitable endoscopic method for radical resection of flat colorectal lesions at risk of underlying malignancy. Additionally, the ESD necessitates further improvement because of the excessively time-consuming as well as the intraprocedural technical hindrances and related complications. We found a higher rate of en bloc resections and R0 for ESD than EMR for non-pedunculated colorectal lesions. Nevertheless, despite the lower local recurrence rates, ESD had greater perforation rates and needed lengthier procedural times. The prevailing risk for additional surgery in ESD rather than EMR for complications or oncologic reasons is still uncertain.

Risk of Covert Submucosal Cancer in Patients With Granular Mixed Laterally Spreading Tumors

BACKGROUND AND AIMS

Granular mixed laterally spreading tumors (GM-LSTs) have an intermediate level of risk for submucosal invasive cancer (SMICs) without clear signs of invasion (covert); the optimal resection method is uncertain. We aimed to determine the risk of covert SMIC in GM-LSTs based on clinical and endoscopic factors.

METHODS

We collected data from 693 patients (50.6% male; median age, 69 years) with colorectal GM-LSTs, without signs of invasion, who underwent endoscopic resection (74.2%) or endoscopic submucosal dissection (25.2%) at 7 centers in Italy from 2016 through 2019. We performed multivariate and univariate analyses to identify demographic and endoscopic factors associated with risk of SMIC. We developed a multivariate model to calculate the number needed to treat (NNT) to detect 1 SMIC.

RESULTS

Based on pathology analysis, 66 patients (9.5%) had covert SMIC. In multivariate analyses, increased risk of covert SMIC were independently associated with increasing lesion size (odds ratio per mm increase, 1.02, 95% CI, 1.01-1.03; P = .003) and rectal location (odds ratio, 3.08; 95% CI, 1.62-5.83; P = .004). A logistic regression model based on lesion size (with a cutoff of 40 mm) and rectal location identified patients with covert SMIC with 47.0% sensitivity, 82.6% specificity, and an area under the curve of 0.69. The NNT to identify 1 patient with a nonrectal SMIC smaller than 4 cm was 20; the NNT to identify 1 patient with a rectal SMIC of 4 cm or more was 5.

CONCLUSIONS

In an analysis of data from 693 patients, we found the risk of covert SMIC in patients with GM-LSTs to be approximately 10%. GM-LSTs of 4 cm or more and a rectal location are high risk and should be treated by en-bloc resection. ClinicalTrials.gov, Number: NCT03836131.

Outcomes of Thermal Ablation of the Mucosal Defect Margin After Endoscopic Mucosal Resection: A Prospective, International, Multicenter Trial of 1000 Large Nonpedunculated Colorectal Polyps

BACKGROUND & AIMS

Thermal ablation of the defect margin after endoscopic mucosal resection (EMR-T) for treating large (≥20 mm) nonpedunculated colorectal polyps (LNPCPs) has shown efficacy in a randomized trial, with a 4-fold reduction, in residual or recurrent adenoma (RRA) at first surveillance colonoscopy (SC1). The clinical effectiveness of this treatment, in the real world, remains unknown.

METHODS

We sought to evaluate the effectiveness of EMR-T in an international multicenter prospective trial (NCT02957058). The primary endpoint was the frequency of RRA at SC1. Detailed demographic, procedural, and outcome data were recorded. Exclusion criteria were LNPCPs involving the ileo-caecal valve, the appendiceal orifice, and circumferential LNPCPs.

RESULTS

During 51 months (May 2016-August 2020) 1049 LNPCPs in 1049 patients (median size, 35 mm; interquartile range, 25-45 mm; right colon location, 53.5%) were enrolled. Uniform completeness of EMR-T was achieved in 989 LNPCPs (95.4%). In this study, 755/803 (94.0%) eligible LNPCPs underwent SC1 (median time to SC1, 6 months; interquartile range, 5-7 months). For LNPCPs that underwent complete EMR-T, the frequency of RRA at SC1 was 1.4% (10/707).

CONCLUSIONS

In clinical practice, EMR-T is a simple, inexpensive, and highly effective auxiliary technique that is likely to significantly reduce RRA at first surveillance. It should be universally used for the management of LNPCPs after EMR. https://clinicaltrials.gov; Clinical Trial Number, NCT02957058.

[Clinical Practice Guideline for Endoscopic Resection of Early Gastrointestinal Cancer]

Although surgery was the standard treatment for early gastrointestinal cancers, endoscopic resection is now a standard treatment for early gastrointestinal cancers without regional lymph node metastasis. High-definition white light endoscopy, chromoendoscopy, and image-enhanced endoscopy such as narrow band imaging are performed to assess the edge and depth of early gastrointestinal cancers for delineation of resection boundaries and prediction of the possibility of lymph node metastasis before the decision of endoscopic resection. Endoscopic mucosal resection and/or endoscopic submucosal dissection can be performed to remove early gastrointestinal cancers completely by en bloc fashion. Histopathological evaluation should be carefully made to investigate the presence of risk factors for lymph node metastasis such as depth of cancer invasion and lymphovascular invasion. Additional treatment such as radical surgery with regional lymphadenectomy should be considered if the endoscopically resected specimen shows risk factors for lymph node metastasis. This is the first Korean clinical practice guideline for endoscopic resection of early gastrointestinal cancer. This guideline was developed by using mainly de novo methods and encompasses endoscopic management of superficial esophageal squamous cell carcinoma, early gastric cancer, and early colorectal cancer. This guideline will be revised as new data on early gastrointestinal cancer are collected.

Endoscopic Submucosal Dissection in North America: A Large Prospective Multicenter Study

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) in Asia has been shown to be superior to endoscopic mucosal resection (EMR) and surgery for the management of selected early gastrointestinal cancers. We aimed to evaluate technical outcomes of ESD in North America.

METHODS

We conducted a multicenter prospective study on ESD across 10 centers in the United States and Canada between April 2016 and April 2020. End points included rates of en bloc resection, R0 resection, curative resection, adverse events, factors associated with failed resection, and recurrence post-R0 resection.

RESULTS

Six hundred and ninety-two patients (median age, 66 years; 57.8% were men) underwent ESD (median lesion size, 40 mm; interquartile range, 25-52 mm) for lesions in the esophagus (n = 181), stomach (n = 101), duodenum (n = 11), colon (n = 211) and rectum (n = 188). En bloc, R0, and curative resection rates were 91.5%, 84.2%, and 78.3%, respectively. Bleeding and perforation were reported in 2.3% and 2.9% of the cases, respectively. Only 1 patient (0.14%) required surgery for adverse events. On multivariable analysis, severe submucosal fibrosis was associated with failed en bloc, R0, and curative resection and higher risk for adverse events. Overall recurrence was 5.8% (31 of 532) at a mean follow-up of 13.3 months (range, 1-60 months).

CONCLUSIONS

In this large multicenter prospective North American experience, we demonstrate that ESD can be performed safely, effectively, and is associated with a low recurrence rate. The technical resection outcomes achieved in this study are in line with the current established consensus quality parameters and further support the implementation of ESD for the treatment of select gastrointestinal neoplasms; ClinicalTrials.gov, Number: NCT02989818.

"Unresectable" polyp management utilizing advanced endoscopic techniques results in high rate of colon preservation

PURPOSE

"Endoscopically unresectable" benign polyps identified during screening colonoscopy are often referred for segmental colectomy. Application of advanced endoscopic techniques can increase endoscopic polyp resection, sparing patients the morbidity of colectomy. This retrospective case-control study aimed to evaluate the success of colon preserving resection of "endoscopically unresectable" benign polyps using advanced endoscopic techniques including endoscopic mucosal resection, endoscopic submucosal dissection, endoluminal surgical intervention, full-thickness laparo-endoscopic excision, and combined endo-laparoscopic resection.

METHODS

A prospectively maintained institutional database identified 95 patients referred for "endoscopically unresectable" benign polyps from 2015 to 2018. Cases were compared to 190 propensity score matched controls from the same database undergoing elective laparoscopic colectomy for other reasons. Primary outcome was rate of complete endoscopic polyp removal. Secondary outcomes included length of stay, unplanned 30-day readmission and reoperation, 30-day mortality, and post-procedural complications.

RESULTS

Advanced endoscopic techniques achieved complete polyp removal without colectomy in 66 patients (70%). Failure was most commonly associated with previously attempted endoscopic resection and occult malignancy. Compared with matched colectomy controls, endoscopic polyp resection resulted in significantly shorter hospital length of stay (1.13 ± 2.41 vs 3.89 ± 4.57 days; p < 0.001), lower unplanned 30-day readmission (1.1% vs 7.7%; p < 0.05), and fewer postoperative complications (4.2% vs 33.9%; p < 0.001). Unplanned 30-day reoperation (2.1% vs 4.4%; p = 0.34) and 30-day mortality (0% vs 0.6%; p = 0.75) trended lower.

CONCLUSIONS

Endoscopic resection of complex polyps can be highly successful, and it is associated with favorable outcomes and decreased morbidity when compared with segmental colon resection. Attempting colon preservation using these techniques is warranted.

Endoscopic full-thickness resection versus endoscopic submucosal dissection in the treatment of colonic neoplastic lesions ≤ 30 mm-a single-center experience

Endoscopic full-thickness resection (FTR) is a novel technique of endoscopic treatment of colorectal neoplastic lesions not suitable for endoscopic polypectomy or mucosal resection. FTR appears to be a reasonable alternative to technically demanding endoscopic submucosal dissection (ESD) for lesions ≤ 30 mm. However, comparison between FTR and ESD has not been published yet and their mutual positioning in the treatment algorithm is still unclear. The purpose of the analysis was to evaluate efficacy and safety of FTR in the treatment of colorectal lesions ≤ 30 mm by comparing prospectively followed FTR cohort to retrospective ESD cohort in the setting of single tertiary endoscopy center. Primary outcomes were technical success rate, R0 resection and curative resection rate, and complication rate. A total of 52 patients in FTR and 50 patients in ESD group were treated between 2015 and 2018. Technical success rate was significantly higher in FTR group (92 vs. 74%, P = 0.01) as well as R0 resection rate (85 vs. 62%, P = 0.01) and curative resection rate (75 vs. 56%, P = 0.01). Complications occurred more frequently in ESD group (40 vs. 13%, P = 0.002), mainly due to high incidence of electrocoagulation syndrome (24 vs. 0%). Total procedure time was substantially shorter in FTR group (26.4 ± 11.0 min vs. estimated 90-240 min). Local residual neoplastic lesions were detected numerically more often in FTR group (12 vs. 5%, P = 0.12). No patient died during follow-up. Compared to ESD, FTR proved significantly higher technical success rate, higher R0 and curative resection rate, and shorter procedure time. In the FTR group, there were significantly less complications but higher incidence of local residual neoplasia. Further research including randomized trials is needed to compare both resection techniques.

Bioinformatic analysis reveals an exosomal miRNA-mRNA network in colorectal cancer

BACKGROUND

Exosomes play important roles in angiogenesis, drug resistance, and metastasis of colorectal cancer (CRC), but the underlying mechanism has seldom been reported. Herein, our study aimed to reveal an exosomal miRNA-mRNA network involved in CRC by performing bioinformatical analysis.

METHODS

The mRNA and miRNA data of colon adenocarcinoma and rectal adenocarcinoma were downloaded from The Cancer Genome Atlas (TCGA) database, and exosomal miRNAs data were downloaded from the GEO dataset GSE39833. The differential expression analysis was performed using "limma" and "edgeR". Target mRNAs of miRNAs were predicted using FunRich 3.1.3, miRNAtap and multiMiR. The candidate mRNAs and exosomal miRNAs were obtained by intersecting two groups of differentially expressed miRNAs and intersection of the differential expressed mRNAs and the target mRNAs, respectively. Key mRNAs and exosomal miRNAs were identified by the least absolute shrinkage and selection operator regression analysis, and used to construct the exosomal miRNA-mRNA network. The network verified was by receiver operating characteristic curve, GEPIA and LinkedOmics. Functional enrichment analysis was also performed for studied miRNAs and mRNAs.

RESULTS

A total of 6568 differentially expressed mRNAs and 531 differentially expressed miRNAs from TCGA data, and 166 differentially expressed exosomal miRNAs in GSE39833 dataset were identified. Next, 16 key mRNAs and five key exosomal miRNAs were identified from the 5284 candidate mRNAs and 61 candidate exosomal miRNAs, respectively. The exosomal miRNA-mRNA network with high connectivity contained 13 hub mRNAs (CBFB, CDH3, ETV4, FOXQ1, FUT1, GCNT2, GRIN2D, KIAA1549, KRT80, LZTS1, SLC39A10, SPTBN2, and ZSWIM4) and five hub exosomal miRNAs (hsa-miR-126, hsa-miR-139, hsa-miR-141, hsa-miR-29c, and hsa-miR-423). The functional annotation revealed that these hub mRNAs were mainly involved in the regulation of B cell receptor signaling pathway and glycosphingolipid biosynthesis related pathways. All hub mRNAs and hub exosomal miRNAs exhibited high diagnosis value for CRC. Furthermore, the association of the hub mRNAs with overall survival, stages, and MSI phenotype of CRC revealed their important roles in CRC progression.

CONCLUSION

This study constructed an exosomal miRNA-mRNA network which may play crucial roles in the carcinogenesis and progression of CRC, thus providing potential diagnostic biomarkers and therapeutic targets for CRC.

The Most Influential Publications on Endoscopic Submucosal Dissection: A Bibliometric Analysis

Background/Aims: Endoscopic submucosal dissection (ESD) is the first-line treatment for superficial gastrointestinal neoplasms with negligible lymph node metastasis. It has evolved through improvements in expertise and equipment, increased understanding of indications and short- and long-term outcomes, and better management of complications. This study aimed to assess and characterize the most influential publications in ESD research.Materials and Methods: We searched the top 50 most cited articles using Web of Science Core Collection (WoSCC) and Google Scholar (GS) from the inception of these services to January 2019. The top 50 Altmetric Attention Score (AAS) articles based on online media mentions were also searched. Each article was evaluated for the number of citations, title, journal, and publication year.Results: The number of citations for the top 50 WoSCC articles on ESD ranged from 37 to 199; Endoscopy published the most articles (20%). Among the top 50 GS articles, Gastrointestinal Endoscopy published the most ESD articles (34%) and the most shared AAS articles (42.6%). PubMed Central article citations in WoSCC or GS showed significant correlation with those from each metric, unlike AAS. The words with the highest relevance scores were “submucosal tunnel dissection,” “guideline,” “novel submucosal gel,” “adhesive material,” “cell sheet,” “esophageal ulcer,” “hemospray,” and “endoscopic closure,” while the following words were influential: “meta-analysis,” “esophageal stricture,” “perforation,” “bleeding,” “fibrin glue,” “artificial ulcer,” “porcine model” and “esophageal squamous cell neoplasia,” excluding “ESD.”Conclusions: This study presents a detailed list of influential articles, journals, and topic words.

Personalizing Polypectomy Techniques Based on Polyp Characteristics

Polypectomy is an essential skill for all endoscopists performing lower gastrointestinal endoscopy. Different polypectomy tools and techniques have evolved and it is important that endoscopists are familiar with these so they can select the most appropriate technique for each polyp. This narrative review updates the different concepts in tailoring polypectomy technique to the characteristics of polyps. Effective polypectomy requires different components, including the following: careful evaluation of the polyp; decision making about optimal polyp management; actual polypectomy, which includes careful positioning of the endoscope and polyp; and postpolypectomy evaluation of the results (for completeness of resection and prophylaxis of complications).

Clinical practice guideline for endoscopic resection of early gastrointestinal cancer

Although surgery was the standard treatment for early gastrointestinal cancers, endoscopic resection is now a standard treatment for early gastrointestinal cancers without regional lymph node metastasis. High-definition white light endoscopy, chromoendoscopy, and image-enhanced endoscopy such as narrow band imaging are performed to assess the edge and depth of early gastrointestinal cancers for delineation of resection boundaries and prediction of the possibility of lymph node metastasis before the decision of endoscopic resection. Endoscopic mucosal resection and/or endoscopic submucosal dissection can be performed to remove early gastrointestinal cancers completely by en bloc fashion. Histopathological evaluation should be carefully made to investigate the presence of risk factors for lymph node metastasis such as depth of cancer invasion and lymphovascular invasion. Additional treatment such as radical surgery with regional lymphadenectomy should be considered if the endoscopically resected specimen shows risk factors for lymph node metastasis. This is the first Korean clinical practice guideline for endoscopic resection of early gastrointestinal cancer. This guideline was developed by using mainly de novo methods and encompasses endoscopic management of superficial esophageal squamous cell carcinoma, early gastric cancer, and early colorectal cancer. This guideline will be revised as new data on early gastrointestinal cancer are collected.

Clinical Practice Guideline for Endoscopic Resection of Early Gastrointestinal Cancer

Although surgery was the standard treatment for early gastrointestinal cancers, endoscopic resection is now a standard treatment for early gastrointestinal cancers without regional lymph node metastasis. High-definition white light endoscopy, chromoendoscopy, and image-enhanced endoscopy such as narrow band imaging are performed to assess the edge and depth of early gastrointestinal cancers for delineation of resection boundaries and prediction of the possibility of lymph node metastasis before the decision of endoscopic resection. Endoscopic mucosal resection and/or endoscopic submucosal dissection can be performed to remove early gastrointestinal cancers completely by en bloc fashion. Histopathological evaluation should be carefully made to investigate the presence of risk factors for lymph node metastasis such as depth of cancer invasion and lymphovascular invasion. Additional treatment such as radical surgery with regional lymphadenectomy should be considered if the endoscopically resected specimen shows risk factors for lymph node metastasis. This is the first Korean clinical practice guideline for endoscopic resection of early gastrointestinal cancer. This guideline was developed by using mainly de novo methods and encompasses endoscopic management of superficial esophageal squamous cell carcinoma, early gastric cancer, and early colorectal cancer. This guideline will be revised as new data on early gastrointestinal cancer are collected.

Optical evaluation: the crux for effective management of colorectal neoplasia

Advances in minimally invasive tissue resection techniques now allow for the majority of early colorectal neoplasia to be managed endoscopically. To optimize their respective risk-benefit profiles, and, therefore, appropriately select between endoscopic mucosal resection, endoscopic submucosal dissection, and surgery, the endoscopist must accurately predict the risk of submucosal invasive cancer and estimate depth of invasion. Herein, we discuss the evidence and our approach for optical evaluation of large (⩾ 20 mm) colorectal laterally spreading lesions.

Future of Endoscopy: Brief review of current and future endoscopic resection techniques for colorectal lesions

Endoscopic treatment of colorectal lesions has seen major developments in the last decade. It is now considered curative for intramucosal and superficial submucosal cancers. Endoscopic Mucosal Resection in expert hands has very good outcomes with low complication rates but recurrence and inadequate treatment of early cancers remain an issue. This has led to a technical evolution that can lead to one piece resection of neoplasia. This includes a range of techniques from knife assisted snare resection (KAR), endoscopic submucosal dissection (ESD) to full thickness resections. This article reviews all the resection techniques and the evidence base behind them.

Pathology definitions and resection strategies for early colorectal neoplasia: Eastern versus Western approaches in the post-Vienna era

There is a well-known discrepancy between East and West classifications of colorectal neoplasm, especially "intramucosal carcinoma," categorized as subgroup 4.4 in the Vienna classification, usually recognized as high-grade dysplasia in the United States and as carcinoma in situ in Japan. Focusing on management, in the current National Comprehensive Cancer Network algorithm, high-grade dysplasia, carcinoma in situ, and intramucosal carcinoma are managed similarly, whereas submucosal invasion by carcinoma requires en bloc resection. To bridge the differences with regard to these conceptual problems in the definition and management of carcinoma in situ and intramucosal carcinoma, endoscopists and pathologists from Japan and the United States gathered and discussed from their perspectives how to accurately assess specimens of en bloc/piecemeal resection and to effectively predict lymph node metastasis risk.

Endoscopic mucosal resection is effective for laterally spreading lesions at the anorectal junction

OBJECTIVE

The optimal approach for removing large laterally spreading lesions at the anorectal junction (ARJ-LSLs) is unknown. Endoscopic mucosal resection (EMR) is a definitive therapy for colorectal LSLs. It is unclear whether it is an effective modality for ARJ-LSLs.

DESIGN

EMR outcomes for ARJ-LSLs (distal margin of ≤20 mm from the dentate line) in comparison with rectal LSLs (distal margin of >20 mm from the dentate line) were evaluated within a multicentre observational cohort of LSLs of ≥20 mm. Technical success was defined as the removal of all polypoid tissue during index EMR. Safety was evaluated by the frequencies of intraprocedural bleeding, delayed bleeding, deep mural injury (DMI) and delayed perforation. Long-term efficacy was evaluated by the absence of recurrence (either endoscopic or histologic) at surveillance colonoscopy (SC).

RESULTS

Between July 2008 and August 2019, 100 ARJ-LSLs and 313 rectal LSLs underwent EMR. ARJ-LSL median size was 40 mm (IQR 35-60 mm). Median follow-up at SC4 was 54 months (IQR 33-83 months). Technical success was 98%. Cancer was present in three (3%). Recurrence occurred in 15.4%, 6.8%, 3.7% and 0% at SC1-SC4, respectively. Among 30 ARJ-LSLs that received margin thermal ablation, no recurrence was identified at SC1 (0.0% vs 25.0%, p=0.002). Technical success, recurrence and adverse events were not different between groups, except for DMI (ARJ-LSLs 0% vs rectal LSLs 4.5%, p=0.027).

CONCLUSION

EMR is an effective technique for ARJ-LSLs and should be considered a first-line resection modality for the majority of these lesions.

Clinical Practice Guideline for Endoscopic Resection of Early Gastrointestinal Cancer

Although surgery was the standard treatment for early gastrointestinal cancers, endoscopic resection is now a standard treatment for early gastrointestinal cancers without regional lymph node metastasis. High-definition white light endoscopy, chromoendoscopy, and image-enhanced endoscopy such as narrow band imaging are performed to assess the edge and depth of early gastrointestinal cancers for delineation of resection boundaries and prediction of the possibility of lymph node metastasis before the decision of endoscopic resection. Endoscopic mucosal resection and/or endoscopic submucosal dissection can be performed to remove early gastrointestinal cancers completely by <i>en bloc</i> fashion. Histopathological evaluation should be carefully made to investigate the presence of risk factors for lymph node metastasis such as depth of cancer invasion and lymphovascular invasion. Additional treatment such as radical surgery with regional lymphadenectomy should be considered if the endoscopically resected specimen shows risk factors for lymph node metastasis. This is the first Korean clinical practice guideline for endoscopic resection of early gastrointestinal cancer. This guideline was developed by using mainly de novo methods and encompasses endoscopic management of superficial esophageal squamous cell carcinoma, early gastric cancer, and early colorectal cancer. This guideline will be revised as new data on early gastrointestinal cancer are collected.

Impact of observational training on endoscopic mucosal resection outcomes and competency for large colorectal polyps: single endoscopist experience

Background and study aims  Endoscopic mucosal resection (EMR) is standard treatment for large colorectal polyps. However, it is a specialized technique with limited data on the effectiveness of training methods to acquire this skill. The aim of this study was to evaluate the impact of observational training on EMR outcomes and competency in an early-stage endoscopist. Patients and methods  A single endoscopist completed comprehensive EMR training, which included knowledge acquisition and direct observation of EMR cases, and proctored supervision, during the third year of gastroenterology fellowship. After training, EMR was independently attempted on 142 consecutive, large (i. e., ≥ 20 mm), non-pedunculated colorectal polyps between July 2014 and December 2017 (mean age 61.7 years; mean polyp size 30.4 mm; en-bloc resection 55 %). Surveillance colonoscopy for evaluation of residual neoplasia was available for 86 % of the cases. Three primary outcomes were evaluated: endoscopic assessment of complete resection, rate of adverse events (AEs), and rate of residual neoplasia on surveillance colonoscopy. Results  Complete endoscopic resection was achieved in 93 % of cases, the rates of AEs and residual neoplasia were 7.8 % and 7.3 %, respectively. The rate of complete resection remained stable (at 85 % or greater) with increasing experience while rates of AEs and residual neoplasia peaked and decreased after 60 cases. Conclusions  An early-stage endoscopist can acquire the skills to perform effective EMR after completing observational training. At least 60 independent EMRs for large colorectal polyps were required to achieve a plateau for clinically meaningful outcomes.

Long-term follow-up after endoscopic submucosal dissection of colorectal lesions in a Spanish cohort

INTRODUCTION

ESD in the colon is an increasingly important technique in Western countries. There are few studies that include long term follow-up.

AIM

to analyze the long term recurrence free survival rate after ESD and to compare recurrence rates according to different variables.

METHODS

this was a prospective observational study of patients with a planned ESD from September 2008 to December 2015. When it was not possible to achieve an ESD, hybrid ESD was performed, either en bloc or piecemeal. Kaplan-Meier survival curves were used to assess the five year local recurrence free survival rate and the recurrence rate. The results were compared according to different factors.

RESULTS

of the 89 patients scheduled for ESD who were initially enrolled in the study, 69 were finally included for follow-up. ESD was performed in 31 (45%) patients, KAR in eleven (16%) and pKAR in 27 (39%). The median follow-up was 27 months (range 6-60). The five year disease free survival rate was 81%. The average number of endoscopies needed to eliminate recurrence was two (range 2-7) and no patient required surgery for this reason. The recurrence rate was significantly higher in piecemeal resections vs en bloc resections (27% vs 15%, p = 0.036) and R1 resections vs R0 resections (26% vs 0%, p = 0.034). The presence of affected or unknown lateral margins in en bloc resections without other poor prognosis factors had higher recurrence rates but the difference was not statistically significant (28% vs 0%, p = 0.09).

CONCLUSIONS

in our study, the five year disease free survival rate was 81% and no patient required surgery during follow-up. Piecemeal and R1 resections had significantly higher recurrence rates, as well as LM involvement, although this was not statistically significant.

How Is Endoscopic Submucosal Dissection for Gastrointestinal Lesions Being Implemented? Results from an International Survey

Background and Study Aim

Superficial gastrointestinal (GI) neoplasms can be treated with endoscopic mucosal resection (EMR) and/or endoscopic submucosal dissection (ESD). These techniques are widely used in Eastern countries; however, its use in the West is limited. The aim of this study was to evaluate the current implementation of ESD in Western countries.

Methods

Western endoscopists (n = 279) who published papers related to EMR/ESD between 2005 and 2017 were asked to complete an online survey from December 2017 to February 2018.

Results

A total of 58 endoscopists (21%) completed the survey. Thirty performed ESD in the esophagus (52%), 45 in the stomach (78%), 36 in the co-lorectum (62%), and 6 in the duodenum (10%). The median total number of lesions ever treated per endoscopist was 190, with a median number per endoscopist in 2016 of 41 (7 [IQR 1-21], 6 [IQR 4-16], and 28 [5-63] in the esophagus, in the stomach, and in the colon and rectum, respectively). En bloc resection rates were 97% in the esophagus, 95% in the stomach, and 84% in the colorectum. Complete resection (R0) was achieved in 88, 91, and 81%, respectively. Curative rates were 69, 70, and 67%, respectively. Major complications (perforation or delayed bleeding) occurred more often in colorectal ESD (12 vs. 6% in the esophagus and 7% in the stomach). In the upper GI tract, the majority of resected lesions were intramucosal adenocarcinoma (59% in the esophagus; 47% in the stomach), while in the colorectum the majority were adenomas (59%).

Conclusion

ESD seems to be performed by a large number of centers and endoscopists. Our results suggest that ESD is being successfully implemented in Western countries, achieving a good rate of efficacy and safety according to European guidelines.

Endoscopic imaging techniques for detecting early colorectal cancer

PURPOSE OF REVIEW

The detection of early colorectal cancer has improved notably since the introduction of bowel cancer screening programmes. This has created new challenges from endoscopic, histological and therapeutic perspectives. Here, we outline the limitations of current clinical practice and ways of implementing optical diagnosis to overcome these limitations.

RECENT FINDINGS

Virtual chromoendoscopy without magnification for predicting or ruling out deep submucosal invasion is useful in real clinical practice for most lesions. However, magnifying virtual chromoendoscopy is needed to make an accurate diagnosis in nonulcerated narrow-band imaging international colorectal endoscopic (NICE) type 3 lesions or NICE type 2 lesions with depressed areas or of nodular mixed type. Finally, dye-based magnifying chromoendoscopy is needed in Japanese NBI Expert Team 2B lesions assessed with magnifying virtual chromoendoscopy.

SUMMARY

A four-step strategy is proposed, combining white-light assessment, virtual chromoendoscopy without magnification, virtual chromoendoscopy with magnification and dye-based chromoendoscopy with magnification.

Robot-assisted endoscopic submucosal dissection versus conventional ESD for colorectal lesions: outcomes of a randomized pilot study in endoscopists without prior ESD experience (with video)

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) is becoming the preferred method for certain early GI malignancies; however, very few U.S. physicians have adopted this technique. This is in part because of the technically challenging nature of the procedure and the long learning curve. Several endoscopic robots are under development to address these complexities.

METHODS

This is a randomized, controlled, pilot study comparing conventional ESD versus robotic-assisted ESD (RESD) in an ex vivo bovine colon model. Five endoscopists without prior ESD or RESD experience were randomized into 2 groups (group 1, RESD after ESD; group 2, RESD before ESD). A standard template was used to create colonic lesions. The primary outcome was completeness of en bloc resection. Secondary outcomes included differences in procedure time, perforation rate, muscle injury rate, and National Aeronautical and Space Administration Task Load Index (NASA-TLX) to assess physical and mental workload.

RESULTS

Five endoscopists each performed 4 tissue resections (2 RESD and 2 ESD), for a total of 20 procedures. Complete en bloc resection was achieved in all RESD and in 50% of ESD (P < .0001). The perforation rate was higher in the ESD group (60% vs 30%, P = .18). Total procedure time (34.1 vs 88.6 min, P = .001) and dissection time (27.8 vs 79.4 minutes, P = .002) were lower for RESD. The NASA-TLX also revealed better results for RESD (28.4 vs 47.4, P = .01).

CONCLUSIONS

RESD appears to be more effective in obtaining en bloc resection with shorter procedure times and a lower perforation rate compared with conventional ESD as performed by ESD novices. RESD is also associated with lower physical and mental workloads.

Risk factors for early and late adenoma recurrence after advanced colorectal endoscopic resection at an expert Western center

BACKGROUND AND AIMS

Few large Western series examine risk factors for recurrence after endoscopic resection (ER) of large (≥20 mm) colorectal laterally spreading tumors. Recurrence beyond initial surveillance is seldom reported, and differences between residual/recurrent adenoma and late recurrence are not scrutinized. We report the incidence of recurrence at successive surveillance intervals, identify risk factors for recurrent/residual adenoma and late recurrence, and describe the outcomes of ER of recurrent adenomas.

METHODS

Recurrence was calculated for successive surveillance periods after colorectal ER. Multiple logistic regression was used to identify independent risk factors for recurrent/residual adenoma and late recurrence (≥12 months).

RESULTS

Six hundred twenty colorectal ERs were performed, and 456 eligible patients (98%) had completed 3- to 6-month surveillance. Residual/recurrent adenoma (3-6 months) was detected in 8.3%, at 12 months in 6.1%, between 24 and 36 months in 6.4%, and after 36 months in 13.5%. Independent risk factors for residual/recurrent adenoma were piecemeal resection (odds ratio [OR], 13.0; P = .01), adjunctive argon plasma coagulation (OR, 2.4; P = .01), and lesion occupying ≥75% of the luminal circumference (OR, 5.6; P < .001) and for late recurrence were lesion size >60 mm (OR, 6.3; P < .001) and piecemeal resection (OR, 4.4; P = .04). Of 66 patients with recurrence, 5 required surgery, 8 left the treatment pathway, 20 are still receiving ER or surveillance, and 33 had ER with normal subsequent surveillance.

CONCLUSIONS

Recurrence occurs at successive periods of surveillance after ER even beyond 3 years. Aside from piecemeal resection, risk factors for residual/recurrent adenoma and late recurrence are different. Recurrence can be challenging to treat, but surgery is rarely required.

Outcomes of endoscopic resection of large colorectal lesions subjected to prior failed resection or substantial manipulation

PURPOSE

Injudicious attempts at resection and extensive sampling of large colorectal adenomas prior to referral for endoscopic resection (ER) are common. This has deleterious effects, but little is known about the outcomes following ER. We retrospectively analysed the outcomes of ER of large adenomas previously subjected to substantial manipulation.

METHOD

ER of large (≥ 2 cm) colorectal adenomas were grouped according to level of manipulation: prior attempted resection, heavy manipulation (≥ six biopsies or tattoo under lesion) or minimal manipulation (< six biopsies). Outcomes were compared between groups. Independent predictors of outcomes were identified using multiple logistic regression.

RESULTS

Five hundred forty-two lesions (mean size 53.7 mm) were included. Two hundred sixty-five (49%) had been subjected to prior attempted resection or heavy manipulation, 151 (28%) to minimal manipulation, and 126 (23%) were not previously manipulated. ESD techniques were used more frequently than EMR after substantial manipulation. There were no differences in initial success of ER (99%, 98%, 98%, p = 0.71). Prior attempted resection was independently associated with recurrence (OR 2.2, 95% CI 1.1-4.5, p = 0.03) and negatively associated with en bloc resection (OR 0.29, 95% CI 0.1-0.7, p = 0.004). Regardless of level of prior manipulation, there were no differences in sustained endoscopic cure with > 95% of patients overall free from recurrence and avoiding surgery at last follow-up.

CONCLUSION

There is a substantial burden of injudicious lesion manipulation before referral, which makes recurrence more likely and en bloc resection less likely. However, with appropriate expertise, sustained successful endoscopic treatment is achievable for the vast majority of patients treated in a specialist unit.

Cost analysis and outcome of endoscopic submucosal dissection for colorectal lesions in an outpatient setting

BACKGROUND AND STUDY AIMS

Endoscopic submucosal dissection (ESD), a minimally invasive treatment for early gastrointestinal (GI) cancer, is considered challenging and risky in the colorectum. As such, most patients undergoing ESD are hospitalized due to the perceived increased risk of adverse events. The aim of this study was to compare the costs, safety and efficacy of colorectal-ESD in an outpatient vs inpatient setting in a tertiary level center.

METHODS

This is a retrospective study on consecutive patients admitted for colorectal-ESD. Patients were divided into outpatients (Group-A, same-day discharge), and inpatients (Group-B, admitted for at least one night). Data on overall costs, outcomes and adverse events were assessed for each group.

RESULTS

A total of 136 patients were considered. Fourteen were excluded because ESD was not performed due to intraprocedural suspicion of invasive cancer. Eighty-three patients were treated as outpatients (Group-A, 68%) and 39 (Group-B, 32%) were hospitalized. R0-rate was 90.4% in Group-A and 89.7% in Group-B(P = 0.98). One perforation occurred in Group-A (1.2%) and 2 in Group-B(5.1%, P = 0.2). Mean Length of stay (LOS) was 1 day for outpatients and 3.3 days for inpatients. Management of Group-A as outpatients produced a cost savings of 941€ on average per patient.

CONCLUSIONS

Outpatient colorectal-ESD is a feasible, cost-effective strategy to manage superficial colorectal tumors with outcomes comparable to inpatient colorectal-ESD. By using proper selection criteria, outpatient ESD could be considered the first-line approach for most patients.

Accuracy of the Narrow-Band Imaging International Colorectal Endoscopic Classification System in Identification of Deep Invasion in Colorectal Polyps

BACKGROUND & AIMS

T1 colorectal polyps with at least 1 risk factor for metastasis to lymph node should be treated surgically and are considered endoscopically unresectable. Optical analysis, based on the Narrow-Band Imaging International Colorectal Endoscopic (NICE) classification system, is used to identify neoplasias with invasion of the submucosa that require endoscopic treatment. We assessed the accuracy of the NICE classification, along with other morphologic characteristics, in identifying invasive polyps that are endoscopically unresectable (have at least 1 risk factor for metastasis to lymph node).

METHODS

We performed a multicenter, prospective study of data collected by 58 endoscopists, from 1634 consecutive patients (examining 2123 lesions) at 17 university and community hospitals in Spain from July 2014 through June 2016. All consecutive lesions >10 mm assessed with narrow-band imaging were included. The primary end point was the accuracy of the NICE classification for identifying lesions with deep invasion, using findings from histology analysis as the reference standard. Conditional inference trees were fitted for the analysis of diagnostic accuracy.

RESULTS

Of the 2123 lesions analyzed, 89 (4.2%) had features of deep invasion and 91 (4.3%) were endoscopically unresectable. The NICE classification system identified lesions with deep invasion with 58.4% sensitivity (95% CI, 47.5-68.8), 96.4% specificity (95% CI, 95.5-97.2), a positive-predictive value of 41.6% (95% CI, 32.9-50.8), and a negative-predictive value of 98.1% (95% CI, 97.5-98.7). A conditional inference tree that included all variables found the NICE classification to most accurately identify lesions with deep invasion (P < .001). However, pedunculated morphology (P < .007), ulceration (P = .026), depressed areas (P < .001), or nodular mixed type (P < .001) affected accuracy of identification. Results were comparable for identifying lesions that were endoscopically unresectable.

CONCLUSIONS

In an analysis of 2123 colon lesions >10 mm, we found the NICE classification and morphologic features identify those with deep lesions with >96% specificity-even in non-expert hands and without magnification. ClinicalTrials.gov number NCT02328066.

Endoscopic submucosal dissection of 301 large colorectal neoplasias: outcome and learning curve from a specialized center in Europe

Background and study aims  Endoscopic submucosal dissection (ESD) allows en bloc resection of large colorectal lesions but ESD experience is limited outside Asia. This study evaluated implementation of ESD in the treatment of colorectal neoplasia in a Western center. Patients and methods  Three hundred and one cases of colorectal ESD (173 rectal and 128 colonic lesions) were retrospectively evaluated in terms of outcome, learning curve and complications. Results  Median size was 4 cm (range 1 - 12.5). En bloc resection was achieved in 241 cases amounting to an en bloc resection rate of 80 %. R0 resection was accomplished in 207 cases (69 %), RX and R1 were attained in 83 (27 %) and 11 (4 %) cases, respectively. Median time was 98 min (range 10 - 588) and median proficiency was 7.2 cm ² /h. Complications occurred in 24 patients (8 %) divided into 12 immediate perforations, five delayed perforations, one immediate bleeding and six delayed bleedings. Six patients (2 %), all with proximal lesions, had emergency surgery. Two hundred and four patients were followed up endoscopically and median follow-up time was 13 months (range 3 - 53) revealing seven recurrences (3 %). En bloc rate improved gradually from 60 % during the first period to 98 % during the last period. ESD proficiency significantly improved between the first study period (3.6 cm ² /h) and the last study period (10.8 cm ² /h). Conclusions  This study represents the largest material on colorectal ESD in the west and shows that colorectal ESD can be implemented in clinical routine in western countries after appropriate training and achieve a high rate of en bloc and R0 resection with a concomitant low incidence of complications. ESD of proximal colonic lesions should be attempted with caution during the learning curve because of higher risk of complications.