Cold EMR vs. Hot EMR for the removal of sessile serrated polyps larger than 10 mm: a systematic review and meta-analysis.

BACKGROUND: Endoscopic mucosal resection (EMR) appears to be a promising technique for the removal of sessile serrated polyps (SSPs) ≥ 10 mm. To assess the effectiveness and safety of EMR for removing SSPs ≥ 10 mm, we conducted this systematic review and meta-analysis. METHODS: We conducted a thorough search of Embase, PubMed, Cochrane, and Web of Science databases for relevant studies reporting on EMR of SSPs ≥ 10 mm, up until December 2023. Our primary endpoints of interest were rates of technical success, residual SSPs, and adverse events (AE). RESULTS: Our search identified 426 articles, of which 14 studies with 2262 SSPs were included for analysis. The rates of technical success, AEs, and residual SSPs were 100%, 2.0%, and 3.1%, respectively. Subgroup analysis showed that the technical success rates were the same for polyps 10-19 and 20 mm, and en-bloc and piecemeal resection. Residual SSPs rates were similar in en-bloc and piecemeal resection, but much lower in cold EMR (1.0% vs. 4.2%, P = 0.034). AEs rates were reduced in cold EMR compared to hot EMR (0% vs. 2.9%, P = 0.168), in polyps 10-19 mm compared to 20 mm (0% vs. 4.1%, P = 0.255), and in piecemeal resection compared to en-bloc (0% vs. 0.7%, P = 0.169). CONCLUSIONS: EMR is an effective and safe technique for removing SSPs ≥ 10 mm. The therapeutic effect of cold EMR is superior to that of hot EMR, with a lower incidence of adverse effects. PROSPERO REGISTRATION NUMBER: CRD42023388959.

[Usefulness and safety of observing anorectal lesions by colon capsule endoscopy].

We investigated the findings of rectoanal lesions in 190 patients who underwent colon capsule endoscopy (CCE) at our hospital. Internal hemorrhoids were observed in 70 (36.8%) patients and rectal polyps in 19 (10%) patients. When conventional endoscopy (colonoscopy and double balloon endoscopy) was considered the gold standard, the sensitivity and specificity of rectal polyps were 75% and 93.4%, respectively, and those of internal hemorrhoids were 88.9% and 92.7%, respectively. The prevalence of constipation was significantly higher in the false-negative group for internal hemorrhoids, and the colonic transit time was significantly shorter in the false-negative and false-positive groups for rectal polyps. No adverse events occurred in any of the patients. CCE might be a useful and safe examination method for rectoanal lesions.

Characteristics and risk factors for colorectal polyps among children in an urban area of Wenzhou, China: a retrospective case control study.

BACKGROUND: Scarce evidence exists on pediatric colorectal polyp risk factors. This study explored the clinical manifestations, morphological and pathological characteristics of, and risk factors for pediatric colorectal polyps. METHODS: This retrospective case-control study included children who received colonoscopy, divided into a colorectal polyp group and a normal control group based on colonoscopy results. The risk factors for colorectal polyps in children were analyzed through logistic regression analysis. RESULTS: The mean age of children with polyps was 6.77 ± 3.44 years. Polyps were detected predominantly in males (72.9%); hematochezia was the primary clinical manifestation (80.25%). Most polyps were juvenile (88.9%) and solitary (87.7%); 50.6% were located in the rectosigmoid area. Univariate analysis showed that gender (P = 0.037), age (P < 0.001), family aggregation (P < 0.001), specific immunoglobulin E (sIgE) (P < 0.001), platelet count (P = 0.001), aspartate aminotransferase (AST) (P = 0.016), meat intake (P = 0.010), and vegetable intake (P < 0.001) were significantly associated with colorectal polyps. Age ≤ 6 years (3-6 years: OR: 26.601, 95% CI: 3.761-160.910; < 3 years: OR: 22.678, 95% CI: 1.873-274.535), positive family aggregation (OR: 3.540, 95% CI: 1.177-10.643), positive sIgE (OR:2.263, 95% CI: 1.076-4.761), and higher meat intake (OR:1.046, 95% CI: 1.029-1.063) were risk factors for pediatric colorectal polyps in logistic regression analysis. Higher vegetable intake (OR: 0.993, 95% CI: 0.986-1.000) was a protective factor against pediatric colorectal polyps. The area under the curve (AUC) of meat intake in the receiver operating characteristic (ROC) curve analysis for predicting colorectal polyps was 0.607; the best cut-off value was 92.14 g/d (P = 0.010, 95% CI: 0.527-0.687). The meat and vegetable intake combination AUC in predicting pediatric colorectal polyps was 0.781 (P < 0.001, 95% CI: 0.718-0.845). CONCLUSIONS: Juvenile, solitary, and located in the rectosigmoid region polyps are most common in children. Hematochezia is the main clinical manifestation. Most polyps were, but multiple and proximally located polyps were also detected. Age ≤ 6 years, especially 3-6 years, positive family aggregation, positive sIgE, and higher meat intake are risk factors for pediatric colorectal polyps. A higher vegetable intake is a protective factor.

The efficacy and safety of cold snare polypectomy with submucosal injection for the removal of polyps less than 20 mm in size: a systematic review and meta-analysis.

BACKGROUND AND AIM: Neoplastic polyp removal is important for colorectal cancer prevention. Endoscopists have proposed cold snare endoscopic mucosal resection (CS-EMR) as a solution to solve positive cutting edges and postoperative bleeding. However, many controversies regarding its specific performance in practice have been reported. The aim of this pooled analysis was to report the efficacy and safety of CS-EMR. METHODS: PubMed/Medline, Embase, Google Scholar, and the Cochrane Library searched up to January 2022 to identify studies in which CS-EMR was performed for the removal of colorectal polyps measuring less than 20 mm. The primary outcome was the complete resection rate (CRR), and the secondary outcome was the rate of adverse events. RESULTS: Eleven studies were included in the final analysis, which included 861 colorectal polyps. The overall CRR with CS-EMR was 96.3% (95% CI, 93.9-98.2%). The early and delayed bleeding rates of CS-EMR were 3.1% (95% CI, 1.2-5.5%) and 1.4% (95% CI, 0.6-2.4%), respectively. There were no statistical significances between CS-EMR and cold snare polypectomy (CSP) in terms of the CRR and adverse events, as well as CS-EMR and hot snare endoscopic mucosal resection (HS-EMR). CONCLUSIONS: For resecting colorectal polyps measuring ≤20 mm, CS-EMR is an effective attempt. However, compared with CSP and HS-EMR, CS-EMR did not improve the efficiency and safety of polypectomy as expected. Multicenter randomized controlled trials are needed to compare CSP with CS-EMR in the resection of <10 mm polyps and HSP with CS-EMR in the resection of ≥10 mm polyps.

Hierarchical contribution of individual lifestyle factors and their interactions on adenomatous and serrated polyp risk.

BACKGROUND: Individual colorectal polyp risk factors are well characterized; however, insights into their pathway-specific interactions are scarce. We aimed to identify the impact of individual risk factors and their joint effects on adenomatous (AP) and serrated polyp (SP) risk. METHODS: We collected information on 363 lifestyle and metabolic parameters from 1597 colonoscopy participants, resulting in over 521,000 data points. We used multivariate statistics and machine-learning approaches to assess associations of single variables and their interactions with AP and SP risk. RESULTS: Individual factors and their interactions showed common and polyp subtype-specific effects. Abdominal obesity, high body mass index (BMI), metabolic syndrome, and red meat consumption globally increased polyp risk. Age, gender, and western diet associated with AP risk, while smoking was associated with SP risk. CRC family history was associated with advanced adenomas and diabetes with sessile serrated lesions. Regarding lifestyle factor interactions, no lifestyle or dietary adjustments mitigated the adverse smoking effect on SP risk, whereas its negative effect was exacerbated by alcohol in the conventional pathway. The adverse effect of red meat on SP risk was not ameliorated by any factor, but was further exacerbated by western diet along the conventional pathway. No modification of any factor reduced the negative impact of metabolic syndrome on AP risk, whereas increased fatless fish or meat substitutes' intake mitigated its effect on SP risk. CONCLUSIONS: Individual risk factors and their interactions for polyp formation along the adenomatous and serrated pathways are strongly heterogeneous. Our findings may facilitate tailored lifestyle recommendations and contribute to a better understanding of how risk factor combinations impact colorectal carcinogenesis.

The efficacy and safety of cold snare versus hot snare polypectomy for endoscopic removal of small colorectal polyps: a systematic review and meta-analysis of randomized controlled trials.

PURPOSE: The optimal technique for removing small colorectal polyps ranging from 5 to 10 mm in size remains uncertain. In order to compare the efficacy and adverse events between cold snare polypectomy (CSP) and hot snare polypectomy (HSP) for removing small polyps, we conducted a systematic review and meta-analysis of available randomized controlled trials. METHODS: We conducted a comprehensive search of MEDLINE, EMBASE, and the Cochrane Library databases from 1998 to May 2023 to identify randomized controlled trials that evaluated the efficacy and safety of cold snare polypectomy (CSP) and hot snare polypectomy (HSP) for resecting small colorectal polyps. The primary outcome measure was the incomplete resection rate (IRR). RESULTS: Seven studies that met our study criteria, with a total of 3178 included polyps, were included in our analysis. The incomplete resection rate (IRR) was found to be significantly higher in the CSP group compared to the HSP group (risk ratio [RR] 1.57 [1.17-2.11], P = 0.003). Although the CSP group had a higher local recurrence rate than the HSP group, the difference was not statistically significant (RR: 3.98 [0.66-23.84], P = 0.13). The polyp retrieval rates were not significantly different between the two groups (RR: 1.00 [0.99-1], P = 0.22). Perforation was not reported or mentioned in any of the seven studies. The overall immediate bleeding rate was significantly higher in the CSP group than the HSP group (RR: 2.26 [1.63-3.14], P < 0.001), but immediate postpolypectomy bleeding requiring additional intervention was similar between the groups (RR: 1.08 [0.54-2.17], P = 0.82). The delayed bleeding rate (RR: 0.83 [0.45-1.55], P = 0.56) and specific polypectomy time (RR: -0.46 [-1.05-0.12], P = 0.12) were also similar between the groups. CONCLUSIONS: The meta-analysis shows a significantly higher IRR for CSP compared with HSP when removing small polyps.

Endoscopic mucosal resection using cold snare versus hot snare in treatment for 10-19 mm non-pedunculated colorectal polyps: protocol of a non-inferiority randomised controlled study.

INTRODUCTION: Cold polypectomy has the advantages of simple operation, less time-consuming and fewer complications. Guidelines have recommended cold snare polypectomy (CSP) to resect small polyps sized ≤5 mm and sessile polyps sized 6-9 mm. However, evidence is scarce regarding cold resection for non-pedunculated polyps sized ≥10 mm. Cold snare endoscopic mucosal resection (CS-EMR) combining CSP and submucosal injection was designed to improve the complete resection rate and reduce adverse events. We hypothesise that CS-EMR is non-inferior to conventional hot snare endoscopic mucosal resection (HS-EMR) in the resection of 10-19 mm non-pedunculated colorectal polyps. METHODS AND ANALYSIS: This study is a prospective, randomised, open-label, non-inferiority, single-centre trial. Outpatients scheduled to undergo a colonoscopy and present eligible polyps will be randomised to receive either CS-EMR or HS-EMR. The primary endpoint is the complete resection. Considering that HS-EMR of 10-19 mm colorectal polyps will yield a complete resection rate of at least 92% and a non-inferiority margin of -10%, a total of 232 polyps will be included (one-sided α, 2.5%; ß, 20%). The analyses are intended to evaluate first non-inferiority (lower limit 95% CI greater than -10% for group difference) and then superiority (lower limit 95% CI>0%) if non-inferiority is achieved. Secondary endpoints include en-bloc resection, the occurrence of adverse events, the use of endoscopic clips, resection time and cost. ETHICS AND DISSEMINATION: The study has been approved by the institutional review board of the Peking Union Medical College Hospital (No. K2203). All participants in the trial will provide written informed consent. The results of this trial will be published in an open-access way. TRIAL REGISTRATION NUMBER: NCT05545787.

Cold Versus Hot Snare Polypectomy for Colorectal Polyps: An Updated Systematic Review and Meta-analysis of Randomized Controlled Trials.

BACKGROUND AND OBJECTIVE: Endoscopic polypectomy is an excellent tool for colon cancer prevention. With the innovation of novel resection techniques, the best method is still being investigated. Hence, we aim to evaluate the efficacy and safety of cold snare polypectomy (CSP) versus hot snare polypectomy (HSP) for colorectal polyp resection. METHODS: A systematic review and meta-analysis synthesizing evidence from randomized controlled trials retrieved from PubMed, EMBASE, WOS, SCOPUS, and CENTRAL until July 16, 2022. We pooled dichotomous outcomes using risk ratio (RR) with the corresponding CI. This review's protocol was prospectively registered in PROSPERO with ID: CRD42022347496. RESULTS: We included 18 randomized controlled trials with a total of 4317 patients and 7509 polyps. Pooled RR favored HSP regarding the complete resection rate (RR: 0.96 with 95% CI: 0.95, 1, P = 0.03) and local recurrence incidence (RR: 5.74 with 95% CI: 1.27, 25.8, P = 0.02). Pooled RR favored CSP regarding the colonoscopy time (mean difference: -6.50 with 95% CI: -7.55, -5.44, P = 0.00001) and polypectomy time (mean difference: -57.36 with 95% CI: -81.74, -32.98, P = 0.00001). There was no difference regarding the incidence of immediate bleeding ( P = 0.06) and perforation ( P = 0.39); however, HSP was associated with more incidence of delayed bleeding ( P = 0.01), abdominal pain ( P = 0.007), and postresection syndrome ( P = 0.02). DISCUSSION: HSP is associated with a higher complete resection and lower recurrence rates; however, HSP is also associated with a higher incidence of adverse events. Therefore, improving the complete resection rate with CSP still warrants more innovation, giving the technique safety and shorter procedure duration.

[Analysis of risk factors for post-polypectomy bleeding and polyp recurrence after colonoscopic polypectomy in children].

Objective: To explore the incidence and the risk factors of post-polypectomy bleeding and polyp recurrence after colonoscopic high-frequency electrocoagulation snare polypectomy. Methods: Clinical data of 1 826 children who underwent colonoscopic high-frequency electrocoagulation snare polypectomy in the Children's Hospital, Zhejiang University School of Medicine from January 2009 to December 2020 was retrospectively analyzed. Demographic characteristics, endoscopic manifestations, pathological features, diagnosis, occurrence of post-polypectomy bleeding and polyp recurrence were collected. The associated risk factors were analyzed by Logistic regression. Results: A total of 1 826 children (1 191 males and 635 females) with 1 967 polypectomies were included. The age was 4.6 (3.2, 6.4) years at initial diagnosis. According to the initial colonoscopy, 1 611 children (88.2%) had solitary polyps, 1 707 children (93.5%) had pedicled polyps, 1 151 children (63.0%) had polyps involving the rectum, and 1 757 children (96.2%) had hamartomatous polyps. Polyposis syndromes were diagnosed in 73 children (4.0%). The post-polypectomy bleeding occurrence was 3.8% (75/1 967). Polyps recurred in 88 children (4.8%). Girls (OR=2.01, 95%CI 1.26-3.23) and sessile polyps (OR=2.28, 95%CI 1.15-4.49) were risk factors for post-polypectomy bleeding (both P<0.05). Multiple polyps (OR=17.49, 95%CI 9.82-31.18), right-colon involvement (OR=3.44, 95%CI 1.89-6.26) and non-hamartoma (OR=2.51, 95%CI 1.04-6.07) were risk factors for polyp recurrence (all P<0.05). Conclusions: Colonoscopic high-frequency electrocoagulation snare polypectomy has low incidence of post-polypectomy bleeding and polyp recurrence. Female patients and sessile polyps have higher risk for post-polypectomy bleeding. Multiple polyps, right-colon involvement and non-hamartoma polyps increase the risk for polyp recurrence.

Risk Factors for Colorectal Polyps and Cancer.

Colorectal cancer (CRC) is a common malignancy in the U.S. and worldwide. Most CRC cases arise from precancerous adenomatous and serrated polyps. Established risk factors for conventional adenomas and CRC include age, male sex, family history, obesity and physical inactivity, and red meat intake. White race and tobacco and alcohol use are important risk factors for serrated polyps, which have a distinct risk factor profile compared to conventional adenomas. A history of abdominopelvic radiation, acromegaly, hereditary hemochromatosis, or prior ureterosigmoidostomy also increases CRC risk. Understanding these risk factors allows for targeted screening of high-risk groups to reduce CRC incidence.

Combined endoscopic and laparoscopic surgery for the treatment of complex benign colonic polyps (CELS): Observational study.

PURPOSE: Combined endoscopic and laparoscopic surgery (CELS) has emerged as a promising method for managing complex benign lesions that would otherwise require major colonic resection. The aim of this study was to describe the different techniques and to evaluate the safety of CELS, assess its outcomes in a technique that is scarcely widespread in our environment. METHOD: Observational retrospective study, short-term outcomes of patients undergoing CELS for benign colon polyps from October 2018 to June 2020 were evaluated. Postoperative outcomes, length of hospital stay and pathological findings were evaluated. RESULTS: Seventeen consecutive patients underwent CELS during the study period. The median size of the lesion was 3.5 cm (range 2.5-6.5 cm), the most frequent location was the cecum (10 from 17). Most patients treated with CELS underwent an endoscopic-assisted laparoscopic wedge resection (11 from 17). In four patients this resection was combined with another CELS technique, and two patients underwent an endoscopic-assisted laparoscopic segment resection. The success rate of CELS in our series was in 14 from 17 (82.4%). The median operative time was 85 min (range 50-225 min). The median hospital stay was 2 days (range 1-15 days). One patient experienced an organ/space surgical site infection which did not require further intervention. Four lesions were shown to be malignant by postoperative pathology study. CONCLUSION: CELS is a safe and multidisciplinar technique that requires collaboration between gastroenterologists and surgeons. It can be considered as an alternative to colonic resection for complex benign colonic polyps.

A Pilot Randomized Trial of Polypectomy Techniques for 4 to 6 mm Colonic Polyps.

BACKGROUND AND GOALS: There is variation in polypectomy techniques for resection of small polyps. Aim was to compare techniques for 4 to 6 mm polyps for recurrent adenoma, efficiency, and adverse events and to establish methodological factors for definitive trial. MATERIALS AND METHODS: The study was a randomized controlled trial. Outpatients with ≥1, 4 to 6 mm polyps were randomized to cold forceps (CF), cold snare (CS), and hot snare (HS). Polypectomy site was marked with SPOT to assess for recurrence at the original polypectomy site during surveillance colonoscopy. To assess feasibility of a definitive trial we measured (1) rates of patient refusal, participation, ineligibility; (2) retention; (3) recurrent neoplasia; and (4) sample size for a definitive trial. RESULTS: Three hundred fifty-three patients were randomized to 1 of the 3 polypectomy techniques, of whom 260 (73.6%) completed the initial colonoscopy (mean age 57 y, 50.4% women), with 91, 87, and 82 patients randomized to CF, CS, and HS polypectomy, respectively. Mean time for polyp resection for CF, CS, and HS were 198.8, 58.5, and 96.8 seconds, respectively, with CS and HS requiring less time than CF (P<0.001). One hundred sixty-four (63.1%) completed surveillance colonoscopy. Polyp recurrences were 9 (14.5%) with CF, 5 (9.6%) with CS, and 0 (0%) with HS. Although the recurrence relative risks with CF and CS polypectomy were 1.84 and 1.65 as compared with HS, respectively, neither was statistically significant. CONCLUSIONS: CS and HS polypectomy require less time than CF. HS polypectomy may have a lower risk for recurrent neoplasia. High attrition rate is a challenge in conducting randomized controlled trial with polyp recurrence as endpoint.

The Role of Clips in Preventing Delayed Bleeding After Colorectal Polyp Resection: An Individual Patient Data Meta-Analysis.

BACKGROUND & AIMS: Nonpedunculated colorectal polyps are normally endoscopically removed to prevent neoplastic progression. Delayed bleeding is the most common major adverse event. Clipping the resection defect has been suggested to reduce delayed bleedings. Our aim was to determine if prophylactic clipping reduces delayed bleedings and to analyze the contribution of polyp characteristics, extent of defect closure, and antithrombotic use. METHODS: An individual patient data meta-analysis was performed. Studies on prophylactic clipping in nonpedunculated colorectal polyps were selected from PubMed, Embase, Web of Science, and Cochrane database (last selection, April 2020). Authors were invited to share original study data. The primary outcome was delayed bleeding ≤30 days. Multivariable mixed models were used to determine the efficacy of prophylactic clipping in various subgroups adjusted for confounders. RESULTS: Data of 5380 patients with 8948 resected polyps were included from 3 randomized controlled trials, 2 prospective, and 8 retrospective studies. Prophylactic clipping reduced delayed bleeding in proximal polyps ≥20 mm (odds ratio [OR], 0.62; 95% confidence interval [CI], 0.44-0.88; number needed to treat = 32), especially with antithrombotics (OR, 0.59; 95% CI, 0.35-0.99; number needed to treat = 23; subgroup of anticoagulants/double platelet inhibitors: n = 226; OR, 0.40; 95% CI, 0.16-1.01; number needed to treat = 12). Prophylactic clipping did not benefit distal polyps ≥20 mm with antithrombotics (OR, 1.41; 95% CI, 0.79-2.52). CONCLUSIONS: Prophylactic clipping reduces delayed bleeding after resection of nonpedunculated, proximal colorectal polyps ≥20 mm, especially in patients using antithrombotics. No benefit was found for distal polyps. Based on this study, patients can be identified who may benefit from prophylactic clipping. (PROSPERO registration number CRD42020104317.).

Outcomes of Deep Mural Injury After Endoscopic Resection: An International Cohort of 3717 Large Non-Pedunculated Colorectal Polyps.

BACKGROUND & AIMS: Although perforation is the most feared adverse event associated with endoscopic mucosal resection (EMR), limited data exists concerning its management. Therefore, we sought to evaluate the short- and long-term outcomes of intra-procedural deep mural injury (DMI) in an international multi-center observational cohort of large (≥20 mm) non-pedunculated colorectal polyps (LNPCPs). METHODS: Consecutive patients who underwent EMR for a LNPCP ≥20 mm were evaluated. Significant DMI (S-DMI) was defined as Sydney DMI Classification type III (muscularis propria injury, target sign) or type IV/V (perforation without or with contamination, respectively). The primary outcome was successful S-DMI defect closure. Secondary outcomes included technical success (removal of all visible polypoid tissue during index EMR), surgical referral and recurrence at first surveillance colonscopy (SC1). RESULTS: Between July 2008 to May 2020, 3717 LNPCPs underwent EMR. Median lesion size was 35mm (interquartile range (IQR) 25 to 45mm). Significant DMI was identified in 101 cases (2.7%), with successful defect closure in 98 (97.0%) using a median of 4 through-the-scope clips (TTSCs; IQR 3 to 6 TTSCs). Three (3.0%) patients underwent S-DMI-related urgent surgery. Technical success was achieved in 94 (93.1%) patients, with 46 (45.5%) admitted to hospital (median duration 1 day; IQR 1 to 2 days). Comparing LNPCPs with and without S-DMI, no differences in technical success (94 (93.1%) vs 3316 (91.7%); P = .62) or SC1 recurrence (12 (20.0%) vs 363 (13.6%); P = .15) were identified. CONCLUSIONS: Significant DMI is readily managed endoscopically and does not appear to affect technical success or recurrence.

Outcomes of cold snare piecemeal EMR for nonampullary small-bowel adenomas larger than 1 cm: a retrospective study.

BACKGROUND AND AIMS: Nonampullary small-bowel adenomas ≥10 mm are typically resected using cautery-based polypectomy, which is associated with significant adverse events. Studies have demonstrated the safety and efficacy of piecemeal cold snare EMR for removing large colon polyps. Our aim was to assess the safety and efficacy of cold snare EMR for removal of large adenomas in the small bowel. METHODS: A retrospective study of patients who underwent lift and piecemeal cold snare EMR of small-bowel adenomas ≥1 cm between January 2014 and March 2019 was conducted at a tertiary care medical center. Polyp characteristics at the time of index and surveillance endoscopy were collected. Primary outcomes were residual or recurrent adenoma (RRA) seen on surveillance endoscopy, polyp eradication rate, and number of endoscopic procedures required for eradication. Adverse events including immediate and delayed bleeding, perforation, stricture, pancreatitis, and postpolypectomy syndrome were assessed. RESULTS: Of 43 patients who underwent piecemeal cold snare EMR, 39 had follow-up endoscopy. Polyps ranged in size from 10 to 70 mm (mean, 26.5 mm). RRA was found in 18 patients (46%), with increased polyp size correlating with higher recurrence (P < .001). Polyp eradication was observed in 35 patients (89%), requiring a median of 2 (range, 1-6) endoscopic procedures. Only 1 patient (2.3%) had immediate postprocedural bleeding. No cases of perforation or postpolypectomy syndrome were seen. CONCLUSIONS: Piecemeal cold snare EMR may be a feasible, safe, and efficacious technique for small-bowel polyps >10 mm. Prospective, randomized studies are needed to assess how outcomes compare with traditional cautery-based polypectomy.

Possible protective role of metformin therapy on colonic polyps in acromegaly: an exploratory cross-sectional study.

CONTEXT: Colonic polyps occur in 30-40% of acromegalic patients, increasing the risk of colon carcinoma. Although debated, there is emerging evidence that metformin may play a protective role in diabetic and non-diabetic patients with colonic polyps and its use in chemoprevention is currently explored. OBJECTIVE: Evaluate the prevalence of colonic polyps in acromegalic patients treated or not with metformin and explore its possible protective role. DESIGN: Exploratory cross-sectional study in two tertiary Italian referral centres. MET: hods: Out of 153 acromegalic patients, we selected 58 patients (36-82 years; f: 33) who had at least one colonoscopy performed within the first 2 years of diagnosis. Presence of colonic polyps/cancer and related risk factors, current metformin and acetylsalicylic acid intake, disease duration, therapies for acromegaly, hormonal and metabolic parameters were assessed. RESULTS: An overall prevalence of 36% polyps was found. Based on the presence of polyps, we identified two groups, comparable for age, BMI, disease duration, glucose, insulin, HOMA-IR, HbA1c, GH and IGF-I levels. Of the patients with polyps (including three adenocarcinomas) only 24% were treated with metformin vs 57% of patients without polyps. Multivariate analysis confirmed a significant negative association between colonic polyps and metformin intake (OR: 0.22, 95% CI: 0.06-0.77, P = 0.01), whereas no significant association was found between polyps and age (P = 0.10), overweight/obesity (P = 0.54), smoking (P = 0.15), acetylsalicylic acid intake (P = 0.99), disease duration (P = 0.96), somatostatin analogues treatment (P = 0.70). CONCLUSIONS: These findings, though deriving from an exploratory study, could suggest a protective role of metformin on the development of colonic polyps in acromegaly, and need to be confirmed in an extended study population.

Serrated polyps: innocent or guilty?

Serrated lesions represent a group of lesions with different genetic and biological features causing important clinical repercussions. Three types of serrated lesions are identified: hyperplastic, sessile adenomas (with and without dysplasia) and traditional serrated adenomas. Such lesions are now recognized as precancerous lesions.The carcinogenic process of serrated lesions follows a pathway including: alterations concerning activation of mitogen and protein kinase regulating the extracellular signal of other intracellular kinases (MAPK-ERK), inhibition of the apoptosis and hypermethylation of DNA and instability of microsatellites. Like for adenomatous polyps, the risk factors for serrated lesions are environmental factors, related to lifestyle and diet. The cancerogenic risk is increased by excessive alcohol consumption, obesity and poor intake of folate. When a high number of colorectal polyps with architecture serrated is diagnosed, it could be considered as serrated polyposis syndrome (SPS). According the most recent ESGE guidelines, the diagnostic criteria of the SPS, are: at least 5 polyps resected proximal to the sigmoid colon, 2 of which> 10 mm, or >20 serrated lesions of any size distributed in the entire colon. This condition presents a high risk for personal and/or familiar CRC, for this reason a regular screening colonoscopy should be performed in these patients and in their first-degree relatives.