A total of 6626 patients with CRC who were initially referred for endoscopic polypectomy were enrolled from the Surveillance Epidemiology and End Results Database.

Results: Most enrolled patients (6557/6626, 99.0%) were at T0-T1 stage (American Joint Committee on Cancer staging system). Propensity score matching (PSM) and inverse probability of treatment weighting (IPTW) were used to reduce selection bias, which resulted in balanced groups of patients with and without lymphadenectomy, with no difference in CSS (p = .99 and .074, respectively). In the subgroup analysis, insufficient lymphadenectomy (lymph node yield [LNY] < 12) was associated with poor CSS compared with no lymphadenectomy. The multivariate analysis identified adequate lymphadenectomy with an LNY ≥ 12 as an independent favorable prognostic factor. However, nearly half of the patients (59/127, 46.5%) referred for lymph node resection did not undergo adequate lymphadenectomy.

The prognosis of CSS cannot be improved by lymphadenectomy for most patients (T0-T1) who are referred for endoscopic therapy because of the low rate of lymph node metastasis. Nonetheless, adequate lymphadenectomy should be performed instead of diagnostic lymph node resection if lymph node involvement is suspected.

Partial resection of colon polyps induces submucosal fibrosis, making subsequent resection attempts more difficult. Some consider that partially resected lesions require specialized techniques such as endoscopic submucosal dissection, full-thickness resection, or surgery. We investigated whether traditional endoscopic resection methods were safe and effective.

We report results of endoscopic resection of previously partially resected colorectal polyps by means of conventional resection methods (snare resection with or without injection and/or avulsion) and compare outcomes with lesions without previous partial resection. This is a retrospectively evaluated assessment of a prospectively collected database at a single tertiary academic center.

From August 12, 2019, to May 14, 2024, 1101 referred colorectal lesions underwent conventional resection and at least 1 surveillance colonoscopy. The last follow-up colonoscopy included in the study was performed on July 19, 2024. Out of the 1101 lesions, 220 had previous partial resection by means of snare, hot biopsy forceps, or surgical transanal excision. All of these 220 lesions were successfully resected with the use of conventional methods, and recurrence rates at first follow-up (8.2%) were similar to lesions without previous resection (7.8%; P = .889), as was the perforation rate (0.5% vs 0.3%). Compared with lesions with no previous resection, previously partially resected lesions were more often resected by means of electrocautery (94.1% vs 64.2%; P < .001), and required the cap technique (36.4% v. 17.4%; P < .001) and avulsion (65.5% v 28.8%; P < .001).

While specialized resection techniques are increasingly advocated to manage fibrotic colorectal lesions, we demonstrate conclusively that experts can successfully and safely manage previously partially resected colorectal lesions with the use of conventional techniques.

Nonlifting large nonpedunculated colorectal polyps (NL-LNPCPs) account for 15% of LNPCPs and are effectively managed by endoscopic mucosal resection (EMR) with adjunctive cold-forceps avulsion with adjuvant snare-tip soft coagulation (CAST). Recurrence rates >10% at surveillance colonoscopy are however a significant limitation. We aimed to compare the outcomes of CAST plus margin thermal ablation (MTA) versus CAST alone for NL-LNPCPs.Prospective observational data on consecutive patients with NL-LNPCPs treated by EMR and CAST at a single tertiary center were retrospectively evaluated. Two cohorts were established: the pre-MTA period (January 2012-June 2017) and the MTA period (July 2017-October 2023). The primary outcome was the residual/recurrent adenoma (RRA) rate at first surveillance colonoscopy (SC1). Secondary outcomes included the RRA rate at SC2 and adverse events.Over 142 months, 300 patients underwent EMR and CAST for LNPCP: 103 lesions pre-MTA and 197 with MTA. At SC1 and SC2, recurrence was lower in the MTA cohort compared with the pre-MTA cohort (5.0% vs. 18.8% and 0.8% vs. 10.0%, respectively; both P<0.001). Adverse events were similar between the two cohorts for deep mural injury types III-V (pre-MTA 2.9% vs. MTA 5.6%; P=0.29) and delayed bleeding (pre-MTA 8.7% vs. MTA 7.1%; P=0.49). On multivariate analysis, MTA was the only variable independently associated with a reduced likelihood of recurrence (odds ratio 0.20, 95%CI 0.07-0.54; P=0.001).For NL-LNPCPs, MTA in combination with CAST is safe and effective and reduces recurrence at SC1 in comparison with CAST alone.

Large non-pedunculated colorectal polyps ≥20 mm (LNPCPs) constitute approximately 1% of all colorectal polyps and present a spectrum of risks, including overt and covert submucosal invasive cancer (T1 colorectal cancer (CRC)). Importantly, a curative resection may be achieved for LNPCPs with superficial T1 CRC (T1a or T1b <1000 µm into submucosa), if an enbloc R0 excision (clear margins) with favourable histology is achieved (ie, absence of high-grade tumour budding, lympho-vascular invasion, and poor differentiation). Thus, while consensus recommendations advocate for endoscopic resection as the primary treatment option for LNPCPs, thorough optical assessment is imperative for selecting the most suitable ER strategy. In this review, we highlight the critical components of optical evaluation that assist in predicting the risk of T1 CRC, including morphology (Paris and LST classifications), surface pit/vascular pattern (JNET and Kudo classifications), and lesion location. Different resection modalities, including endoscopic submucosal dissection and endoscopic mucosal resection are discussed, along with important considerations that may influence the resection strategy of choice, such as access to the LNPCP and submucosal fibrosis.

In the United States, while most nonmalignant polyps are effectively treated through endoscopic removal, colectomy remains a treatment option for selected cases of nonmalignant polyps (NMPs) and colon cancer. This study aimed to compare postoperative outcomes for colectomies in these two conditions, hypothesizing similar complication rates.

We conducted a retrospective review of the American College of Surgeons National Surgical Quality Improvement Program database from 2015 to 2021, including patients who underwent elective colectomies for colon cancer or NMPs. Using a 2:1 propensity score matching for demographics, American Society of Anesthesiologists classification, surgical methods, and comorbidities, we evaluated outcomes such as 30-d mortality, complications, anastomotic leakage, and hospital stay duration.

A total of 47,960 patients, including 30,549 colon cancer patients and 17,411 NMP patients, were included after propensity score matching analysis. We concluded that there was no significant difference in mortality and reoperation rates which were 0.6% and 3.3% in patients undergoing colectomy with colon cancer, compared to 0.5% and 3.1% in those with NMP, respectively [P = 0.64, P = 0.21,]. In addition, the anastomotic leak rates were remarkably similar in both the colon cancer (2.4%) and NMP (2.2%) groups. [P = 0.13]. Most of the 30-d postoperative surgical complications, such as sepsis, septic shock, wound disruption, and urinary tract infection exhibited similar incidence rates, however, some of them, such as readmission, pulmonary embolism, and length of stay, varied between the groups.

Our findings underscore the similar postoperative outcomes between colon cancer and NMP groups, advocating for consideration of advanced endoscopic techniques for NMPs to potentially enhance patient care and outcomes.

The efficacy of colorectal endoscopic mucosal resection (EMR) is limited by recurrence and the necessity for conservative surveillance. Margin thermal ablation (MTA) after EMR has reduced the incidence of recurrence at the first surveillance colonoscopy at 6 months (SC1). Whether this effect is durable to second surveillance colonoscopy (SC2) is unknown. We evaluated long-term surveillance outcomes in a cohort of LNPCPs that have undergone MTA.

LNPCPs undergoing EMR and MTA from four academic endoscopy centres were prospectively recruited. EMR scars were evaluated at SC1 and in the absence of recurrence, SC2 colonoscopy was conducted in a further 12 months. A historical control arm was generated from LNPCPs that underwent EMR without MTA. The primary outcome was recurrence at SC2 in all LNPCPs with a recurrence-free scar at SC1.

1152 LNPCPs underwent EMR with complete MTA over 90 months until October 2022. 854 LNPCPs underwent SC1 with 29/854 (3.4%) LNPCPs demonstrating recurrence. 472 LNPCPs free of recurrence at SC1 underwent SC2. 260 LNPCPs with complete SC2 follow-up formed the control arm from January 2012 to May 2016. Recurrence at SC2 was significantly less in the MTA arm versus controls (1/472 (0.2%) vs 9/260 (3.5%); p<0.001)).

LNPCPs that have undergone successful EMR with MTA and are free of recurrence at SC1 are unlikely to develop recurrence in subsequent surveillance out to 2 years. Provided the colon is cleared of synchronous neoplasia, the next surveillance can be potentially extended to 3-5 years. Such an approach would reduce costs and enhance patient compliance.

Underwater endoscopic mucosal resection (UEMR) has emerged as a promising alternative to conventional endoscopic mucosal resection (CEMR) for the treatment of colorectal laterally spreading tumors (LSTs). This study aimed to compare the efficacy and safety of UEMR and CEMR in managing LSTs measuring 10-30 mm.

A post hoc analysis was performed on 88 patients with 88 colorectal LSTs, who were randomly assigned to two treatment groups: 42 with CEMR and 46 with UEMR. The primary outcome was the rate of R0 resection, defined as the absence of neoplastic cells at the resection margin. The secondary outcomes included en bloc resection rates, procedure times, and postprocedural complications. The data were analyzed via chi-square tests, t tests, and the Mann-Whitney U test where appropriate.

No significant difference was found in the R0 resection rate between UEMR and CEMR. However, UEMR achieved a significantly higher en bloc resection rate, particularly for LSTs ranging from 20 to 30 mm (42.9% for CEMR vs. 100% for UEMR; p = 0.009). Additionally, UEMR resulted in a shorter median procedure time (85.0 s for UEMR vs. 207.5 s for CEMR; p < 0.001). There was no significant difference in bleeding complications or the number of clips used between the two groups.

Compared with CEMR, UEMR offers a higher en bloc resection rate and a shorter procedure time, particularly for larger lesions, without increasing the risk of complications. UEMR should be considered a preferred option for managing colorectal LSTs, especially those measuring 20-30 mm.

Conventional hot snare endoscopic mucosal resection (H-EMR) is effective for the management of large (≥20 mm) non-pedunculated colon polyps (LNPCPs) however, electrocautery-related complications may incur significant morbidity. With a superior safety profile, cold snare EMR (C-EMR) of LNPCPs is an attractive alternative however evidence is lacking. We conducted a randomised trial to compare the efficacy and safety of C-EMR to H-EMR.

Flat, 15-50 mm adenomatous LNPCPs were prospectively enrolled and randomly assigned to C-EMR or H-EMR with margin thermal ablation at a single tertiary centre. The primary outcome was endoscopically visible and/or histologically confirmed recurrence at 6 months surveillance colonoscopy. Secondary outcomes were clinically significant post-EMR bleeding (CSPEB), delayed perforation and technical success.

177 LNPCPs in 177 patients were randomised to C-EMR arm (n=87) or H-EMR (n=90). Treatment groups were equivalent for technical success 86/87 (98.9%) C-EMR versus H-EMR 90/90 (100%); p=0.31. Recurrence was significantly greater in C-EMR (16/87, 18.4% vs 1/90, 1.1%; relative risk (RR) 16.6, 95% CI 2.24 to 122; p<0.001).Delayed perforation (1/90 (1.1%) vs 0; p=0.32) only occurred in the H-EMR group. CSPEB was significantly greater in the H-EMR arm (7/90 (7.8%) vs 1/87 (1.1%); RR 6.77, 95% CI 0.85 to 53.9; p=0.034).

Compared with H-EMR, C-EMR for flat, adenomatous LNPCPs, demonstrates superior safety with equivalent technical success. However, endoscopic recurrence is significantly greater for cold snare resection and is currently a limitation of the technique.

NCT04138030.

Colorectal cancer is one of the most common forms of cancer in Norway, and typically develops from colorectal polyps. For benign colorectal polyps, endoscopic removal is recommended to avoid unnecessary surgery. This study identifies the extent of surgical treatment of benign polyps in the period 1 January 2008-31 December 2021.

We obtained statistics from the Norwegian Patient Registry on the surgical resection of benign colorectal polyps, number of colonoscopies performed and number of patients with the diagnostic code for benign polyp in the study period. Population size from Statistics Norway was used to calculate annual incidences of the procedure.

The number of patients with benign polyps increased from 211 per 100 000 population to 444 per 100 000 during the study period. The number of colonoscopies increased from 9.4 per 1 000 population to 16.7 per 1 000. The number of surgical resections of benign colorectal polyps per year increased from 4.2 per 100 000 population to 6.3 per 100 000. The total number of unique patients with benign polyps in the period was 215 736, of which 2.1 % received surgical treatment, with the figures varying from 2.0 % in 2008 to 1.6 % in 2021.

Our results show that surgical treatment of benign polyps is still widespread in Norway. This impacts on patient safety and health economics. We propose the establishment of multidisciplinary teams and enhanced endoscopic competence in Norwegian health trusts.

Large nonpedunculated colorectal polyps ≥ 20 mm (LNPCPs) comprise 1% of all colorectal lesions. LNPCPs are more likely to contain advanced histology such as high-grade dysplasia and submucosal invasive cancer (SMIC). Endoscopic resection is the first-line approach for management of these lesions. Endoscopic resection options include endoscopic mucosal resection (EMR), cold-snare EMR (EMR), endoscopic submucosal dissection (ESD) and endoscopic full-thickness resection (EFTR). This review aimed to critically evaluate current endoscopic resection techniques.

Evidence-based selective resection algorithms should inform the most appropriate endoscopic resection technique. Most LNPCPs are removed by conventional EMR but there has been a trend toward C-EMR for endoscopic resection of LNPCPs. More high-quality trials are required to better define the limitations of C-EMR. Advances in our understanding of ESD technique, has clarified its role within the colorectum. More recently, the development of a full thickness resection device (FTRD) has allowed the curative endoscopic resection of select lesions.

Endoscopic resection should be regarded as the principle approach for all LNPCPs. Underpinned by high-quality research, endoscopic resection has become more nuanced, leading to improved patient outcomes.

Colorectal cancer is a highly prevalent malignancy and a significant driver of cancer mortality and health-related expenditure worldwide. Polyp removal reduces the incidence and mortality of colorectal cancer. In 2024, endoscopists have an array of resection modalities at their disposal. Each technique requires a unique skillset and has individual advantages and limitations. Consequently, resection in the colorectum requires an evidence-based algorithm approach that considers these factors.

A literature review of endoscopic resection for colonic neoplasia was conducted. Best supporting scientific evidence was summarized for the endoscopic resection of diminutive polyps, large ≥20 mm lesions and polyps containing invasive cancer. Factors including resection modality, complications and lesion selection were explored to inform an algorithm approach to colorectal resection.

Endoscopic resection in the colorectum is not a one-size-fits-all approach. Detailed understanding of polyp size, location, morphology and predicted histology are critical factors that inform appropriate endoscopic resection practice.

Minimally invasive innovations have transformed coloproctology. Specific to colorectal cancer (CRC), there has been a shift towards less invasive surgical techniques and use of endoscopic resection as an alternative for low risk T1 CRC. The role of endoscopic resection is however much more extensive: It is now considered the first line management strategy for most large (≥ 20 mm) non-pedunculated colorectal polyps, the majority of which are benign. This is due to the well-established efficacy, safety, and cost-effectiveness of endoscopic techniques compared to surgery. Multiple endoscopic modalities now exist with distinct risk-benefit profiles and their outcomes are further improved by site-specific technical modifications, auxiliary techniques, and adverse event mitigation strategies. Endoscopic capacity continues to evolve with emerging endoscopic techniques and expanding applications, particularly in the confines of a multi-disciplinary setting.

1:  ESGE recommends cold snare polypectomy (CSP), to include a clear margin of normal tissue (1-2 mm) surrounding the polyp, for the removal of diminutive polyps (≤ 5 mm).Strong recommendation, high quality of evidence. 2:  ESGE recommends against the use of cold biopsy forceps excision because of its high rate of incomplete resection.Strong recommendation, moderate quality of evidence. 3:  ESGE recommends CSP, to include a clear margin of normal tissue (1-2 mm) surrounding the polyp, for the removal of small polyps (6-9 mm).Strong recommendation, high quality of evidence. 4:  ESGE recommends hot snare polypectomy for the removal of nonpedunculated adenomatous polyps of 10-19 mm in size.Strong recommendation, high quality of evidence. 5:  ESGE recommends conventional (diathermy-based) endoscopic mucosal resection (EMR) for large (≥ 20 mm) nonpedunculated adenomatous polyps (LNPCPs).Strong recommendation, high quality of evidence. 6:  ESGE suggests that underwater EMR can be considered an alternative to conventional hot EMR for the treatment of adenomatous LNPCPs.Weak recommendation, moderate quality of evidence. 7:  Endoscopic submucosal dissection (ESD) may also be suggested as an alternative for removal of LNPCPs of ≥ 20 mm in selected cases and in high-volume centers.Weak recommendation, low quality evidence. 8:  ESGE recommends that, after piecemeal EMR of LNPCPs by hot snare, the resection margins should be treated by thermal ablation using snare-tip soft coagulation to prevent adenoma recurrence.Strong recommendation, high quality of evidence. 9:  ESGE recommends (piecemeal) cold snare polypectomy or cold EMR for SSLs of all sizes without suspected dysplasia.Strong recommendation, moderate quality of evidence. 10:  ESGE recommends prophylactic endoscopic clip closure of the mucosal defect after EMR of LNPCPs in the right colon to reduce to reduce the risk of delayed bleeding.Strong recommendation, high quality of evidence. 11:  ESGE recommends that en bloc resection techniques, such as en bloc EMR, ESD, endoscopic intermuscular dissection, endoscopic full-thickness resection, or surgery should be the techniques of choice in cases with suspected superficial invasive carcinoma, which otherwise cannot be removed en bloc by standard polypectomy or EMR.Strong recommendation, moderate quality of evidence.

Metabolic reprogramming plays a key role in cancer progression and clinical outcomes; however, the patterns and primary regulators of metabolic reprogramming in colorectal cancer (CRC) are not well understood.

To explore the role of nicotinamide adenine dinucleotide phosphate oxidase 4 (NOX4) in promoting progression of CRC.

We evaluated the expression and function of dysregulated and survival-related metabolic genes using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes. Consensus clustering was used to cluster CRC based on dysregulated metabolic genes. A prediction model was constructed based on survival-related metabolic genes. Sphere formation, migration, invasion, proliferation, apoptosis and clone formation was used to evaluate the biological function of NOX4 in CRC. mRNA sequencing was utilized to explore the alterations of gene expression NOX4 over-expression tumor cells. In vivo subcutaneous and lung metastasis mouse tumor model was used to explore the effect of NOX4 on tumor growth.

We comprehensively analyzed 3341 metabolic genes in CRC and identified three clusters based on dysregulated metabolic genes. Among these genes, NOX4 was highly expressed in tumor tissues and correlated with worse survival. In vitro, NOX4 overexpression induced clone formation, migration, invasion, and stemness in CRC cells. Furthermore, RNA-sequencing analysis revealed that NOX4 overexpression activated the mitogen-activated protein kinase-MEK1/2-ERK1/2 signaling pathway. Trametinib, a MEK1/2 inhibitor, abolished the NOX4-mediated tumor progression. In vivo, NOX4 overexpression promoted subcutaneous tumor growth and lung metastasis, whereas trametinib treatment can reversed the metastasis.

Our study comprehensively analyzed metabolic gene expression and highlighted the importance of NOX4 in promoting CRC metastasis, suggesting that trametinib could be a potential therapeutic drugs of CRC clinical therapy targeting NOX4.

(1) Background: Large colonic polyps during colonoscopy can be managed by Endoscopic mucosal resection (EMR). To decrease the polyp recurrence rate, thermal ablation methods like argon plasma coagulation (APC) and snare tip soft coagulation (STSC) have been introduced. We performed this network meta-analysis to assess the efficacy and safety of these modalities. (2) Methods: We performed a comprehensive literature review, through 5 January 2024, of databases including Embase, PubMed, SciELO, KCI, Cochrane Central, and Web of Science. Using a random effects model, we conducted a frequentist approach network meta-analysis. The risk ratio (RR) with 95% confidence interval (CI) was calculated. Safety and efficacy endpoints including rates of recurrence, bleeding, perforation, and post polypectomy syndrome were compared. (3) Results: Our search yielded a total of 13 studies with 2686 patients. Compared to placebo, both APC (RR: 0.33 CI: 0.20-0.54, p < 0.01) and STSC (RR: 0.27, CI: 0.21-0.34, p < 0.01) showed decreased recurrence rates. On ranking, STSC showed the lowest recurrence rate, followed by APC and placebo. Regarding individual adverse events, there was no statistically significant difference between either of the thermal ablation methods and placebo. (4) Conclusions: We demonstrated the efficacy and safety of thermal ablation after EMR for decreasing recurrence of adenoma.

Complete closure after endoscopic resection of large nonpedunculated colorectal lesions (LNPCLs) can reduce delayed bleeding but is challenging with conventional through-the-scope (TTS) clips alone. The novel dual-action tissue (DAT) clip has clip arms that open and close independently of each other, facilitating tissue approximation. We aimed to evaluate the rate of complete closure and delayed bleeding with the DAT clip after endoscopic resection of LNPCLs.

This was a multicenter prospective cohort study of all patients who underwent defect closure with the DAT clip after EMR or endoscopic submucosal dissection (ESD) of LNPCLs ≥20 mm from July 2022 to May 2023. Delayed bleeding was defined as a bleeding event requiring hospitalization, blood transfusion, or any intervention within 30 days after the procedure. Complete closure was defined as apposition of mucosal defect margins without visible submucosal areas <3 mm along the closure line.

One hundred seven patients (median age, 64 years; 42.5% women) underwent EMR (n = 63) or ESD (n = 44) of LNPCLs (median size, 40 mm; 74.8% right-sided colon) followed by defect closure. Complete closure was achieved in 96.3% (n = 103) with a mean of 1.4 ± .6 DAT clips and 2.9 ± 1.8 TTS clips. Delayed bleeding occurred in 1 patient (.9%) without requiring additional interventions.

The use of the DAT clip in conjunction with TTS clips achieved high complete defect closure after endoscopic resection of large LNPCLs and was associated with a .9% delayed bleeding rate. Future comparative trials and formal cost-analyses are needed to validate these findings. (Clinical trial registration number: NCT05852457.).

Background and study aims Because of concerns about peri-procedural adverse events (AEs), guidelines recommend anesthetist-managed sedation (AMS) for long and complex endoscopic procedures. The safety and efficacy of physician-administered balanced sedation (PA-BS) for endoscopic mucosal resection (EMR) of large non-pedunculated colorectal polyps (LNPCPs) ≥20 mm is unknown. Patients and methods We compared PA-BS with AMS in a retrospective study of prospectively collected data from consecutive patients referred for management of LNPCPs (NCT01368289; NCT02000141). A per-patient propensity analysis was performed following a 1:2 nearest-neighbor (Greedy-type) match, based on age, gender, Charlson comorbidity index, and lesion size. The primary outcome was any peri-procedural AE, which included hypotension, hypertension, tachycardia, bradycardia, hypoxia, and new arrhythmia. Secondary outcomes were unplanned admissions, 28-day re-presentation, technical success, and recurrence. Results Between January 2016 and June 2020, 700 patients underwent EMR for LNPCPs, of whom 638 received PA-BS. Among them, the median age was 70 years (interquartile range [IQR] 62-76 years), size 35 mm (IQR 25-45 mm), and duration 35 minutes (IQR 25-60 minutes). Peri-procedural AEs occurred in 149 (23.4%), most commonly bradycardia (116; 18.2%). Only five (0.8%) required an unplanned sedation-related admission due to AEs (2 hypotension, 1 arrhythmia, 1 bradycardia, 1 hypoxia), with a median inpatient stay of 1 day (IQR 1-3 days). After propensity-score matching, there were no differences between PA-BS and AMS in peri-procedural AEs, unplanned admissions, 28-day re-presentation rates, technical success or recurrence. Conclusions Physician-administered balanced sedation for the EMR of LNPCPs is safe. Peri-procedural AEs are infrequent, transient, rarely require admission (<1%), and are experienced in similar frequencies to those receiving anesthetist-managed sedation.

 As endoscopic mucosal resection (EMR) of large (≥ 20 mm) adenomatous nonpedunculated colonic polyps (LNPCPs) becomes widely practiced outside expert centers, appropriate training is necessary to avoid failed resection and inappropriate surgical referral. No EMR-specific tool guides case selection for endoscopists learning EMR. This study aimed to develop an EMR case selection score (EMR-CSS) to identify potentially challenging lesions for "EMR-naïve" endoscopists developing competency.

 Consecutive EMRs were recruited from a single center over 130 months. Lesion characteristics, intraprocedural data, and adverse events were recorded. Challenging lesions with intraprocedural bleeding (IPB), intraprocedural perforation (IPP), or unsuccessful resection were identified and predictive variables identified. Significant variables were used to form a numerical score and receiver operating characteristic curves were used to generate cutoff values.

 Of 1993 LNPCPs, 286 (14.4 %) were in challenging locations (anorectal junction, ileocecal valve, or appendiceal orifice), 368 (18.5 %) procedures were complicated by IPB and 77 (3.9 %) by IPP; 110 (5.5 %) procedures were unsuccessful. The composite end point of IPB, IPP, or unsuccessful EMR was present in 526 cases (26.4 %). Lesion size, challenging location, and sessile morphology were predictive of the composite outcome. A six-point score was generated with a cutoff value of 2 demonstrating 81 % sensitivity across the training and validation cohorts.

 The EMR-CSS is a novel case selection tool for conventional EMR training, which identifies a subset of adenomatous LNPCPs that can be successfully and safely attempted in early EMR training.

Despite advances in new approaches for colorectal cancer (CRC) therapy, intravenous chemotherapy remains one of the main treatment options; however, it has limitations associated with off-target toxicity, tumor cell resistance due to molecular complexity and CRC heterogeneity, which lead to tumor recurrence and metastasis. In oncology, nanoparticle-based strategies have been designed to avoid systemic toxicity and increase drug accumulation at tumor sites. Hyaluronic acid (HA) has obtained significant attention thanks to its ability to target nanoparticles (NPs) to CRC cells through binding to cluster-determinant-44 (CD44) and hyaluronan-mediated motility (RHAMM) receptors, along with its efficient biological properties of mucoadhesion. This review proposes to discuss the state of the art in HA-based nanoparticulate systems intended for localized treatment of CRC, highlighting the importance of the mucoadhesion and active targeting provided by this polymer. In addition, an overview of CRC will be provided, emphasizing the importance of CD44 and RHAMM receptors in this type of cancer and the current challenges related to this disease, and important concepts about the physicochemical and biological properties of HA will also be addressed. Finally, this review aims to contribute to the advancement of accuracy treatment of CRC by the design of new platforms based on by HA.

Colorectal strictures related to endoscopic resection (ER) of large nonpedunculated colorectal polyps (LNPCPs) may be problematic. Data on prevalence, risk factors, and management are limited. We report a prospective study of colorectal strictures following ER and describe our approach to management.

We analyzed prospectively collected data over 150 months, until June 2021, for patients who underwent ER for LNPCPs ≥ 40 mm. The ER defect size was graded as < 60 %, 60 %-89 %, or ≥ 90 % of the luminal circumference. Strictures were considered "severe" if patients experienced obstructive symptoms, "moderate" if an adult colonoscope could not pass the stenosis, or "mild" if there was resistance on successful passage. Primary outcomes included stricture prevalence, risk factors, and management.

916 LNPCPs ≥ 40 mm in 916 patients were included (median age 69 years, interquartile range 61-76 years, male sex 484 [52.8 %]). The primary resection modality was endoscopic mucosal resection in 859 (93.8 %). Risk of stricture formation with an ER defect ≥ 90 %, 60 %-89 %, and < 60 % was 74.2 % (23/31), 25.0 % (22/88), and 0.8 % (6 /797), respectively. Severe strictures only occurred with ER defects ≥ 90 % (22.6 %, 7/31). Defects < 60 % conferred low risk of only mild strictures (0.8 %, 6/797). Severe strictures required earlier (median 0.9 vs. 4.9 months; P = 0.01) and more frequent (median 3 vs. 2; P = 0.02) balloon dilations than moderate strictures.

Most patients with ER defects ≥ 90 % of luminal circumference developed strictures, many of which were severe and required early balloon dilation. There was minimal risk with ER defects < 60 %.

Despite advances in endoscopic techniques for management of benign colonic neoplasms, a rise in rates of surgical treatment has been reported. We used a nationally representative cohort to characterize temporal trends, patient characteristics, and outcomes associated with colectomy for colonic neoplasms.

All patients undergoing elective partial colectomy for benign or malignant colonic neoplasms were identified using the 2012-2019 National Inpatient Sample. Those presenting with inflammatory bowel disease, or experiencing intestinal perforation were excluded. Patients with benign neoplasms were classified as the Benign cohort (others: Malignant). Trends, characteristics, and outcomes were assessed between groups.

Of 569,280 colectomy procedures included for analysis, 153,435 (27.0%) were performed for benign lesions. The proportion of Benign operations decreased from 28.6% in 2012 to 23.7% in 2019 (P for trend<0.001). While overall national incidence of colectomy for benign neoplasms decreased from 2012 to 2019 (IRD -1.19, 95%CI -1.20- -1.19), Black patients demonstrated an incremental increase (IRD +0.04, 95%CI +0.02-0.06). On average, Benign was younger (66 [57-72] vs 68 years [58-77], P<0.001), and demonstrated a lower Elixhauser comorbidity index (2 [1-3] vs 3 [2-4], P<0.001), relative to Malignancy. Following adjustment, Benign demonstrated lower odds of in-hospital mortality (AOR 0.61, 95%CI 0.50-0.74; P<0.001), stoma creation (AOR 0.46, 95%CI 0.43-0.50; P<0.001), and infectious complications (AOR 0.68, 95%CI 0.63-0.73; P<0.001).

The present national study identifies a decrease in colectomy for benign polyps from 2012-2019. Future investigations should identify patients who would most benefit from surgical resection and address persistent inequities in access to screening and treatment for colonic neoplasms.

The aim of this study was to evaluate the efficacy of endoscopic polypectomy as a therapeutic treatment for malignant alteration of colorectal polyps. In a 5-year research, 89 patients were included, who were tested and treated at the University Clinical Center Kragujevac, Kragujevac, Serbia, with the confirmed presence of malignant alteration polyps of the colon by colonoscopy, which were removed using the method of endoscopic polypectomy and confirmed by the histopathological examination of the entire polyp. After that, the same group of patients was monitored endoscopically within a certain period, controlling polypectomy locations and the occurrence of a possible remnant of the polyp, in the period of up to 2 years of polypectomy. We observed that, with an increasing size of polyps, there is also an increase in the percentage of the complexity of endoscopic resection and the appearance of remnant with histological characteristics of the invasive cancer. The highest percentage of incomplete endoscopic resection and the appearance of remnant with histological characteristics of the invasive cancer were shown at malignant altered polyps in the field of tubulovillous adenoma. Eighteen patients in total underwent the surgical intervention. In conclusion, our data support the high efficacy of endoscopic polypectomy for the removal of the altered malignant polyp.

Owing to advances in diagnostic technology, the diagnosis of T1 colorectal cancers (CRCs) continues to increase. However, the optimal management of T1 CRCs in the Western Hemisphere remains unclear due to limited population-based data directly comparing the efficacy of endoscopic therapy (ET) and surgical resection (SR). The purpose of this study was to report outcome data from a large Western cohort of patients who underwent ET or SR for early CRCs.

The SEER-18 database was used to identify patients with T1 CRCs diagnosed from 2004 to 2018 treated with ET or SR. Multivariable logistic regression models were employed to identify variables related to lymph node metastasis (LNM). Rates of ET and 1-year relative survival were calculated for each year. Effect of ET or SR on overall survival and cancer-specific survival was compared using Kaplan-Meier method stratified by tumor size and site.

A total of 28,430 T1 CRCs patients were identified from 2004 to 2018 in US, with 22.7% undergoing ET and 77.3% undergoing SR. The incidence of T1 CRCs was 6.15 per 100,000 person-years, with male patients having a higher incidence. Left-sided colon was the most frequent location of tumors. The utilization of ET increased significantly from 2004 to 2018, with no significant change in 1-year relative survival rate. Predictors of LNM were age at diagnosis, sex, race, tumor size, histology, grade, and location. The 5-year relative survival rates were 91.4 and 95.4% for ET and SR, respectively. Subgroup analysis showed that OS and CSS were similar between ET and SR in T1N0M0 left-sided colon cancers with tumors 2 cm or less and in rectal cancers with tumors 1 cm or less.

Our study showed that ET was feasible and safe for patients with left-sided T1N0M0 colon cancers and tumors of 2 cm or less, as well as T1N0M0 rectal cancers and tumors of 1 cm or less. Therefore, the over- and under-use of ET should be avoided by carefully selecting patients based on tumor size and site.

Delayed bleeding is the most frequent complication after endoscopic submucosal dissection (ESD) and endoscopic mucosal resection (EMR) of large colon polyps. Today, prophylactic clipping with through-the-scope clips (TTSCs) is commonly used to reduce the risk of bleeding. However, the over-the-scope clip (OTSC) system might be superior to TTSCs in achieving hemostasis. This study aims to evaluate the efficacy and safety of prophylactic clipping using the OTSC system after ESD or EMR of large colon polyps.

This is a retrospective analysis of a prospective collected database from 2009 until 2021 of three endoscopic centers. Patients with large (≥ 20 mm) colon polyps were enrolled. All polyps were removed by either ESD or EMR. After the resection, OTSCs were prophylactically applied on parts of the mucosal defect with a high risk of delayed bleeding or/and perforation. The main outcome measurement was delayed bleeding.

A total of 75 patients underwent ESD (67%, 50/75) or EMR (33%, 25/75) in the colorectum. The mean resected specimen diameter was 57 mm ± 24.1 (range 22-98 mm). The mean number of OTSCs placed on the mucosal defect was 2 (range 1-5). None of the mucosal defects were completely closed. Intraprocedural bleeding occurred in 5.3% (ESD 2.0% vs. EMR 12.0%; P = 0.105), and intraprocedural perforation occurred in 6.7% (ESD 8% vs. EMR 4%; P = 0.659) of the patients. Hemostasis was achieved in 100% of cases of intraprocedural bleeding, whereas two patients required surgical conversion due to intraprocedural perforation. Among the remaining 73 patients who received prosphylactic clipping, delayed bleeding occurred in 1.4% (ESD 0% vs. EMR 4.2%; P = 0.329), and delayed perforation occurred in 0%.

The prophylactic partial closure of large post-ESD/EMR mucosal defects using OTSCs could serve as an effective strategy to reduce the risk of delayed bleeding and perforation. The prophylactic partial closure of large complex post-ESD/EMR mucosal defects using OTSCs could serve as an effective strategy to reduce the risk of delayed bleeding and perforation.

Residual or recurrent adenoma (RRA) after endoscopic mucosal resection (EMR) of large non-pedunculated colorectal polyps (LNPCPs) of ≥20 mm is a major limitation. Data on outcomes of the endoscopic treatment of recurrence are scarce, and no evidence-based standard exists. We investigated the efficacy of endoscopic retreatment over time in a large prospective cohort.

Over 139 months, detailed morphological and histological data on consecutive RRA detected after EMR for single LNPCPs at one tertiary endoscopy centre were prospectively recorded during structured surveillance colonoscopy. Endoscopic retreatment was performed on cases with evidence of RRA and was performed predominantly using hot snare resection, cold avulsion forceps with adjuvant snare tip soft coagulation or a combination of the two.

213 (14.6%) patients had RRA (168 (78.9%) at first surveillance and 45 (21.1%) thereafter). RRA was commonly 2.5-5.0 mm (48.0%) and unifocal (78.7%). Of 202 (94.8%) cases which had macroscopic evidence of RRA, 194 (96.0%) underwent successful endoscopic therapy and 161 (83.4%) had a subsequent follow-up colonoscopy. Of the latter, endoscopic therapy of recurrence was successful in 149 (92.5%) of 161 in the per-protocol analysis, and 149 (73.8%) of 202 in the intention-to-treat analysis, with a mean of 1.15 (SD 0.36) retreatment sessions. No adverse events were directly attributable to endoscopic therapy. Further RRA after endoscopic therapy was endoscopically treatable in most cases. Overall, only 9 (4.2%, 95% CI 2.2% to 7.8%) of 213 patients with RRA required surgery.Thus 159 (98.8%, 95% CI 95.1% to 99.8%) of 161 cases with initially successful endoscopic treatment of RRA and follow-up remained surgery-free for a median of 13 months (IQR 25.0) of follow-up.

RRA after EMR of LNPCPs can be effectively treated using simple endoscopic techniques with long-term adenoma remission of >90%; only 16% required retreatment. Therefore, more technically complex, morbid and resource-intensive endoscopic or surgical techniques are required only in selected cases.

NCT01368289 and NCT02000141.

Large non-pedunculated colorectal polyps ≥20 mm (LNPCPs) comprise approximately 1% of all colorectal polyps. LNPCPs more commonly contain high-grade dysplasia, covert and overt cancer. These lesions can be resected using several means, including conventional endoscopic mucosal resection (EMR), cold-snare EMR (C-EMR) and endoscopic submucosal dissection (ESD). This review aimed to provide a comprehensive, critical and objective analysis of ER techniques. Evidence-based, selective resection algorithms should be used when choosing the most appropriate technique to ensure the safe and effective removal of LNPCPs. Due to its enhanced safety and comparable efficacy, there has been a paradigm shift towards cold-snare polypectomy (CSP) for the removal of small polyps (<10 mm). This technique is now being applied to the management of LNPCPs; however, further research is required to define the optimal LNPCP subtypes to target and the viable upper size limit. Adjuvant techniques, such as thermal ablation of the resection margin, significantly reduce recurrence risk. Bleeding risk can be mitigated using through-the-scope clips to close defects in the right colon. Endoscopic surveillance is important to detect recurrence and synchronous lesions. Recurrence can be readily managed using an endoscopic approach.

Abdominal ultrasonography after transrectal filling with contrast agent (AU-TFCA) was retrospectively evaluated with respect to determination of T stage and lesion length in patients with colorectal cancer (CRC) who had previously failed colonoscopy because of severe intestinal stenosis.

The population comprised 83 patients with CRC with intestinal stenosis and previously failed colonoscopy who underwent AU-TFCA, and in addition contrast-enhanced computed tomography (CECT) and/or magnetic resonance imaging (MRI), 2 wk before surgery. The diagnostic performance of AU-TFCA and CECT/MRI was evaluated relative to the post-operative pathological results (PPRs) by paired sample t-test, receiver operator characteristic (ROC) curve, Pearson's χ²-test and κ and intraclass correlation coefficients.

The T staging identified via AU-TFCA, but not CECT/MRI, was relatively consistent with that of the PPRs (linearly weighted κ coefficient: 0.558, p < 0.001, and linearly weighted κ coefficient: 0.237, p < 0.001, respectively). The overall diagnostic accuracy of T staging based on AU-TFCA (83.1%) was significantly higher than that based on CECT/MRI (50.6%). Regarding lesion length, the results of AU-TFCA and PPRs were comparable (t = 1.852, p = 0.068), but those of CECT/MRI and PPRs were significantly different (t = 8.450, p < 0.001).

AU-TFCA is effective in evaluation of lesion length and T stage in patients with severely stenotic CRC lesions who previously failed colonoscopy. The diagnostic accuracy of AU-TFCA is significantly better compared with that of CECT/MRI.

As an important management method of the global healthcare system, diagnosis related groups (DRGs) classify patients into different cost groups and pay more attention to the equitable distribution of medical resources and the quality of medical services. At present, most countries have used DRGs to help medical institutions and doctors to treat patients more accurately, avoid the waste of medical resources, and improve treatment efficiency.

The Web of Science database was searched to collect all relevant literature on DRGs from 2013 to 2022. The literature information was imported into CiteSpace, Vosviewer, and Histcite for data analysis and visualization of the results. Analyze the cooperative relationship among the countries, institutions, journals, and authors. The usage trend of keywords; Highlight the content of the cited articles.

The number of articles published in this decade was stable, and the number of citations in 2014 was the highest. The United States and Germany, as the first countries to use the DRGs system, are ahead of other countries in terms of the number and quality of articles. We have carried out content research on the articles with high citations, and summarized the application range of DRGs; classification method; advantages and disadvantages of the application. In general, the development trend of DRGs in foreign countries is to continuously optimize the classification method, expand the scope of application, and improve the application effect. These provide support and reference for the improvement of medical services and the perfection of the medical insurance system.

The application of DRGs can improve the quality and efficiency of medical services, and reduce the waste of medical expenses. It can also promote the rational allocation of medical resources and the equity of medical services. In the future, DRGs will pay more attention to the personalized diagnosis and treatment and fine management of patients, and the sharing and standardization of medical data, to promote the development of medical informatization.

Endoscopic mucosal resection (EMR) is the standard of care for the complete removal of large (≥ 10 mm) nonpedunculated colorectal polyps (LNPCPs). Increased detection of LNPCPs owing to screening colonoscopy, plus high observed rates of incomplete resection and need for surgery call for a standardized approach to training in EMR. 1 : Trainees in EMR should have achieved basic competence in diagnostic colonoscopy, < 10-mm polypectomy, pedunculated polypectomy, and common methods of gastrointestinal endoscopic hemostasis. The role of formal training courses is emphasized. Training may then commence in vivo under the direct supervision of a trainer. 2 : Endoscopy units training endoscopists in EMR should have specific processes in place to support and facilitate training. 3: A trained EMR practitioner should have mastered theoretical knowledge including how to assess an LNPCP for risk of submucosal invasion, how to interpret the potential difficulty of a particular EMR procedure, how to decide whether to remove a particular LNPCP en bloc or piecemeal, whether the risks of electrosurgical energy can be avoided for a particular LNPCP, the different devices required for EMR, management of adverse events, and interpretation of reports provided by histopathologists. 4: Trained EMR practitioners should be familiar with the patient consent process for EMR. 5: The development of endoscopic non-technical skills (ENTS) and team interaction are important for trainees in EMR. 6: Differences in recommended technique exist between EMR performed with and without electrosurgical energy. Common to both is a standardized technique based upon dynamic injection, controlled and precise snare placement, safety checks prior to the application of tissue transection (cold snare) or electrosurgical energy (hot snare), and interpretation of the post-EMR resection defect. 7: A trained EMR practitioner must be able to manage adverse events associated with EMR including intraprocedural bleeding and perforation, and post-procedural bleeding. Delayed perforation should be avoided by correct interpretation of the post-EMR defect and treatment of deep mural injury. 8: A trained EMR practitioner must be able to communicate EMR procedural findings to patients and provide them with a plan in case of adverse events after discharge and a follow-up plan. 9: A trained EMR practitioner must be able to detect and interrogate a post-endoscopic resection scar for residual or recurrent adenoma and apply treatment if necessary. 10: Prior to independent practice, a minimum of 30 EMR procedures should be performed, culminating in a trainer-guided assessment of competency using a validated assessment tool, taking account of procedural difficulty (e. g. using the SMSA polyp score). 11: Trained practitioners should log their key performance indicators (KPIs) of polypectomy during independent practice. A guide for target KPIs is provided in this document.

There are few studies analyzing the cost of endoscopic resection and surgical resection in the treatment of submucosal colorectal cancer.

The objective was to perform a detailed cost analysis of endoscopic resection and surgical resection for submucosal colorectal cancer.

This was a retrospective observational study.

This study was conducted at a tertiary academic center.

Medical records of 484 patients with submucosal colorectal cancer who underwent endoscopic resection or surgical resection between July 2003 and July 2015 were reviewed.

The total costs during index admission and follow-up as well as clinical outcomes between the 2 groups were compared in the whole cohort and propensity score-matched cohort.

In the propensity score-matched analysis ( n = 155 in each group), the endoscopic resection and surgical resection groups did not show significant differences in the rates of procedure-related adverse events (6.5% vs 3.9%; p = 0.304) and recurrence (0.6% vs 1.3%; p > 0.99). Readmission was more common in the endoscopic resection group (40.6% vs 11.0%; p < 0.001) because 64 (41.3%) patients underwent additional surgery for endoscopic noncurative resection. The endoscopic resection group had a lower cost during the index admission (1335.6 vs 6698.4 USD; p < 0.001), whereas the surgical resection group had a lower cost during follow-up (2488.7 vs 5035.7 USD; p < 0.001). The total cumulative cost was lower in the endoscopic resection group (6371.3 vs 9187.1 USD; p < 0.001). The same trend was observed in the whole cohort without propensity score matching.

A limitation of this study was the retrospective nature of analysis.

The total cumulative cost for treatment and follow-up for submucosal colorectal cancer was lower in the endoscopic resection group, which had comparable oncologic outcomes as the surgical resection group. Endoscopic resection can be considered a cost-effective option for initial treatment for submucosal colorectal cancer. See Video Abstract at http://links.lww.com/DCR/B881 .

ANTECEDENTES: Existen pocos estudios que analizan el costo de la resección endoscópica y la resección quirúrgica en el tratamiento del cáncer colorrectal submucoso.OBJETIVO: El objetivo fue realizar un análisis detallado de costos tanto de la resección endoscópica y la resección quirúrgica para el cáncer colorrectal submucoso.DISEÑO: Este fue un estudio observacional retrospectivo.AJUSTE: Este estudio se realizó en un centro académico terciario.PACIENTES: Se revisaron las historias clínicas de 484 pacientes con cáncer colorrectal submucoso que fueron sometidos a resección endoscópica o resección quirúrgica entre julio de 2003 y julio de 2015.PRINCIPALES MEDICIONES DE RESULTADOS: Los costos totales durante la admisión índice y el seguimiento, así como los resultados clínicos entre los dos grupos, fueron comparados en toda la cohorte y la cohorte emparejada por puntuación de propensión.RESULTADOS: En el análisis emparejado por puntuación de propensión ( n = 155 en cada grupo), los grupos de resección endoscópica y resección quirúrgica no mostraron diferencias significativas en las tasas de eventos adversos relacionados con el procedimiento (6,5% vs 3,9%, p = 0,304) y recurrencia (0,6% vs 1,3%, p > 0,99). La readmisión fue más común en el grupo de resección endoscópica (40,6% vs 11,0%, p < 0,001) porque 64 (41,3%) pacientes fueron sometidos a una cirugía adicional para lograr la resección en aquellos casos en que la resección endoscópica no fue curativa. El grupo de resección endoscópica tuvo un costo menor durante el ingreso índice (1335.6 vs 6698.4 USD, p < 0.001), mientras que el grupo de resección quirúrgica tuvo un costo menor durante el seguimiento (2488.7 vs 5035.7 USD, p < 0.001). El costo total acumulado fue menor en el grupo de resección endoscópica (6371,3 vs 9187,1 USD, p < 0,001). La misma tendencia se observó en toda la cohorte sin emparejamiento por puntuación de propensión.LIMITACIONES: La naturaleza retrospectiva del análisis.CONCLUSIONES: El costo total acumulado para el tratamiento y seguimiento del cáncer colorrectal submucoso fue menor en el grupo de resección endoscópica, que tuvo resultados oncológicos comparables a los del grupo de resección quirúrgica. La resección endoscópica puede considerarse una opción rentable para el tratamiento inicial del cáncer colorrectal submucoso. Consulte Video Resumen en http://links.lww.com/DCR/B881 . (Traducción-Dr Osvaldo Gauto ).

Owing to its simplicity, effectiveness, and safety, EMR is the preferred treatment for the majority of large (≥20 mm) nonpedunculated colonic polyps (LNPCPs); however, residual and recurrent adenomas (RRAs) encountered during surveillance constitute a major limitation. Thermal ablation of the post-EMR mucosal defect margin has been shown to be highly efficacious in reducing RRA in a randomized trial setting, but data on effectiveness in clinical practice are scarce. We aimed to determine the effectiveness of this technique for reducing RRAs in routine clinical practice.

We analyzed data collected in 3 hospitals in Israel: Prospective data were available in 2 hospitals where margin thermal ablation with snare-tip soft coagulation (STSC) is routinely performed after EMR of LNPCP (TA-EMR). Only retrospective data were available from the third center, which exclusively did not perform STSC (standard EMR] [S-EMR]), during the study period. Surveillance was performed 4 to 6 months after resection. RRA was assessed endoscopically with high-definition white light and optical chromoendoscopy. The primary endpoint was RRA at first surveillance colonoscopy.

Data from 764 patients with 824 LNPCPs were analyzed. The patient and lesion characteristics were similar between the groups. Four hundred sixty-four LNPCPs were treated by TA-EMR and 360 LNPCPs by S-EMR. RRA at first surveillance colonoscopy was detected in 14 (3.6%) of lesions in the TA-EMR group compared with 96 (31.6%) in the S-EMR group (P < .001; RR = .14; 95% CI, .07-.29). Adverse events were comparable between the 2 groups.

TA-EMR leads to a significant reduction in post-EMR recurrence in routine clinical practice.

BACKGROUND : Pre-resection biopsy (PRB) of large nonpedunculated colorectal polyps (LNPCPs, ≥ 20 mm) is often performed before referral for endoscopic mucosal resection (EMR). How this affects the EMR procedure is unknown. METHODS : This was a retrospective analysis of a prospectively collected cohort of patients with LNPCPs referred for EMR between 2013 to 2016 at an Australian tertiary center. Outcomes were differences between PRB and EMR histology, and effects of PRB on the EMR procedure. RESULTS:  Among 586 LNPCPs, lesions that underwent PRB were larger (median 35 vs. 30 mm; P < 0.007), and more commonly morphologically flat or slightly elevated (P = 0.01) compared with lesions without PRB. PRB histology was upstaged in 26.1 %, downstaged in 13.8 %, and unchanged in 60.1 % after EMR. Sensitivity of PRB was 77.2 % (95 %CI 71.1-82.4) for low grade dysplasia (LGD) and 21.2 % (95 %CI 11.5-35.1) for high grade dysplasia (HGD). Where EMR specimen showed HGD, PRB had detected LGD in 76.9 %. Where EMR specimen showed cancer, PRB had detected dysplasia only. PRB was associated with more submucosal fibrosis (P = 0.001) and intraprocedural bleeding (P = 0.03). EMR success or recurrence was not affected. CONCLUSIONS:  Routine PRB of LNPCP did not reliably detect advanced histology and may have affected EMR complexity. PRB should be utilized with caution in guiding endoscopic management of LNPCPs.

According to current guidelines, more than 70% of patients with invasive submucosal colorectal cancer (T1 CRC) undergo a radical operation with lymph node dissection, even though only ~ 10% have lymph node metastasis (LNM). Hence, there is imperative to develop biomarkers that can help robustly identify LNM-positive patients to prevent such overtreatments. Given the emerging interest in exosomal cargo as a source for biomarker development in cancer, we examined the potential of exosomal miRNAs as LNM prediction biomarkers in T1 CRC.

We analyzed 200 patients with high-risk T1 CRC from two independent cohorts, including a training (n = 58) and a validation cohort (n = 142). Cell-free and exosomal RNAs from pre-operative serum were extracted, followed by quantitative reverse-transcription polymerase chain reactions for a panel of miRNAs.

A panel of four miRNAs (miR-181b, miR-193b, miR-195, and miR-411) exhibited robust ability for detecting LNM in the exosomal vs. cell-free component. We subsequently established a cell-free and exosomal combination signature, successfully validated in two independent clinical cohorts (AUC, 0.84; 95% CI 0.70-0.98). Finally, we developed a risk-stratification model by including key pathological features, which reduced the false positive rates for LNM by 76% without missing any true LNM-positive patients.

Our novel exosomal miRNA-based liquid biopsy signature robustly identifies T1 CRC patients at risk of LNM in a preoperative setting. This could be clinically transformative in reducing the significant overtreatment burden of this malignancy.

Implementing population-based screening programs for colorectal cancer has led to an increase in the detection of large but benign histological lesions. Currently, endoscopic mucosal resection can be considered the standard technique for the removal of benign lesions of the colon due to its excellent safety profile and good clinical results. However, several studies from different geographic areas agree that many benign colon lesions are still referred for surgery. Moreover, the referral rate to surgery is not decreasing over the years, despite the theoretical improvement of endoscopic resection techniques. This article will review the leading causes for benign colorectal lesions to be referred for surgery and the influence of the endoscopist experience on the referral rate. It will also describe how to categorize a polyp as complex for resection and consider an endoscopist as an expert in endoscopic resection. And finally, we will propose a framework for the accurate and evidence-based treatment of complex benign colorectal lesions.

Management of covert submucosal invasive cancer (SMIC) discovered after piecemeal endoscopic mucosal resection (pEMR) of large (>20 mm) non-pedunculated colorectal polyps is challenging. The residual cancer risk is largely unknown. We sought to evaluate this in a large tertiary referral cohort.

Cases of covert SMIC following pEMR were identified and followed. Oncological outcomes after surgery were divided based on residual intramural cancer, lymph node metastases (LNM) or both. Risk factors for residual intramural cancer and LNM were analysed based on the original pEMR histological variables. Risk parameters were analysed with respect to low and high-risk variables for residual intramural cancer and LNM.

Among 3372 cases of large non-pedunculated colorectal polyps, 143 cases of covert SMIC (4.2%) were identified. 109 underwent surgical resection. Histological analysis of pEMR histology was available in 98 of 109 (90%) cases. 62 cases (63%) had no residual malignancy. 36 cases had residual malignancy (residual intramural cancer n=24; LNM n=5; both n=7). All cases of residual intramural cancer could be identified by a R1 histological deep margin. Cases with poor differentiation (PD) and/or lymphovascular invasion (LVI) had a high risk of LNM (12/33), with a very low risk without these criteria (<1%; 0/65). Cases at low risk for LNM with R0 deep margin have a low risk of residual intramural cancer (<1%; 0/35).

The majority of cases of large non-pedunculated colorectal polyps with covert SMIC following pEMR will have no residual malignancy. The risk of residual malignancy can be ascertained from three key variables: PD, LVI and R1 deep margin.

After EMR, prophylactic clipping is often performed to prevent clinically significant post-EMR bleeding (CSPEB) and other adverse events (AEs). Prior evidence syntheses have lacked sufficient power to assess clipping in relevant subgroups or in nonbleeding AEs. We performed a meta-analysis of individual patient data (IPD) from randomized trials assessing the efficacy of clipping to prevent AEs after EMR of proximal large nonpedunculated colorectal polyps (LNPCPs) ≥20 mm.

We searched EMBASE, MEDLINE, Cochrane Central Registry of Controlled Trials, and PubMed from inception to May 19, 2021. Two reviewers screened citations in duplicate. Corresponding authors of eligible studies were invited to contribute IPD. A random-effects 1-stage model was specified for estimating pooled effects, adjusting for patient sex and age and for lesion location and size, whereas a fixed-effects model was used for traditional meta-analyses.

From 3145 citations, 4 trials were included, representing 1248 patients with proximal LNPCPs. The overall rate of CSPEB was 3.5% and 9.0% in clipped and unclipped patients, respectively. IPD were available for 1150 patients, in which prophylactic clipping prevented CSPEB with an odds ratio (OR) of .31 (95% confidence interval [CI], .17-.54). Clipping was not associated with perforation or abdominal pain, with ORs of .78 (95% CI, .17-3.54) and .67 (95% CI, .20-2.22), respectively.

Prophylactic clipping is efficacious in preventing CSPEB after EMR of proximal LNPCPs. Therefore, clip closure should be considered a standard component of EMR of LNPCPs in the proximal colon.