Usefulness of virtual scale endoscope for early gastrointestinal lesions.

Objectives: For early gastrointestinal lesions, size is an important factor in the selection of treatment. Virtual scale endoscope (VSE) is a newly developed endoscope that can measure size more accurately than visual measurement. This study aimed to investigate whether VSE measurement is accurate for early gastrointestinal lesions of various sizes and morphologies. Methods: This study prospectively enrolled patients with early gastrointestinal lesions ≤20 mm in size visually. Lesion sizes were measured in the gastrointestinal tract visually, on endoscopic resection specimens with VSE, and finally on endoscopic resection specimens using a ruler. The primary endpoint was the normalized difference (ND) of VSE measurement. The secondary endpoints were the ND of visual measurement and the variation between NDs of VSE and visual measurements. ND was calculated as (100 × [measured size - true size] / true size) (%). True size was defined as size measured using a ruler. Results: This study included 60 lesions from April 2022 to December 2022, with 20 each in the esophagus, stomach, and colon. The lesion size was 14.0 ± 6.3 mm (mean ± standard deviation). Morphologies were protruded, slightly elevated, and flat or slightly depressed type in 8, 24, and 28 lesions, respectively. The primary endpoint was 0.3 ± 8.8%. In the secondary endpoints, the ND of visual measurement was -1.7 ± 29.3%, and the variability was significantly smaller in the ND of VSE measurement than in that of visual measurement (p < 0.001, F-test). Conclusions: VSE measurement is accurate for early gastrointestinal lesions of various sizes and morphologies.

Is annual screening by fecal immunochemical test necessary after a recent colonoscopy?

Objective: The population-based colorectal cancer screening guidelines in Japan recommend an annual fecal immunochemical test (FIT). However, there is no consensus on the need for annual FIT screening for patients who recently performed a total colonoscopy (TCS). Therefore, we evaluated the repeated TCS results for patients with positive FIT after a recent TCS to assess the necessity of an annual FIT. Methods: We reviewed patients with positive FIT in opportunistic screening from April 2017 to March 2022. The patients were divided into two groups: those who had undergone TCS within the previous 5 years (previous TCS group) and those who had not (non-previous TCS group). We compared the detection rates of advanced neoplasia and colorectal cancer between the two groups. Results: Of 671 patients, 151 had received TCS within 5 years and 520 had not. The detection rates of advanced neoplasia in the previous TCS and non-previous TCS groups were 4.6% and 12.1%, respectively (p < 0.01), and the colorectal cancer detection rates were 0.7% and 1.5%, respectively (no significant difference). The adenoma detection rates were 33.8% in the previous TCS group and 40.0% in the non-previous TCS group (no significant difference). Conclusions: Only a few patients were diagnosed with advanced neoplasia among the patients with FIT positive after a recent TCS. For patients with adenomatous lesions on previous TCS, repeated TCS should be performed according to the surveillance program without an annual FIT. The need for an annual FIT for patients without adenomatous lesions on previous TCS should be prospectively assessed in the future.

How COVID-19 Impacted Colonoscopy Utilization and Colorectal Cancer Detection in Hawai'i in 2020.

The Coronavirus Disease of 2019 (COVID-19) pandemic had a profound impact on colorectal cancer (CRC) screening and diagnostic testing. During the initial months of the pandemic, there was a sharp decline in colonoscopies performed as many areas were on lockdown and elective procedures could not be performed. In later months, even when routine procedures started being scheduled again, some patients became fearful of contracting COVID during colonoscopy or lost their health insurance, leading to further delays in CRC diagnosis by colonoscopy. Previous studies have reported the dramatic decrease in colonoscopy rates and CRC detection at various institutions across the country, but no previous study has been performed to determine rates of colorectal screening by colonoscopy in Hawai'i where the demographics of CRC differ. The team investigated the pandemic's impact on colonoscopy services and colorectal neoplasia detection at several large outpatient endoscopy centers in Hawai'i and also classified new CRC cases by patient demographics of age, sex, and ethnicity. There were fewer colonoscopies performed in these endoscopy centers in 2020 than in 2019 and a disproportionate decrease in CRC cases diagnosed. Elderly males as well as Native Hawaiians/Pacific Islanders were most impacted by this decrease in CRC detection. It is possible there will be an increase in later stage presentation of CRC and eventual CRC related mortality among these patients.

Cold versus hot snare endoscopic mucosal resection for large (≥15 mm) flat non-pedunculated colorectal polyps: a randomised controlled trial.

BACKGROUND AND AIMS: 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. METHODS: 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. RESULTS: 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). CONCLUSION: 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. TRIAL REGISTRATION NUMBER: NCT04138030.

[The prognostic value of colonoscopy grading for acute graft-versus-host disease in patients with malignant hematological disorders after unrelated cord blood transplantation].

Objective: To investigate the prognostic value of enteroscopic grading for the prognostic assessment of patients with malignant hematological diseases who developed intestinal acute graft-versus-host disease (IT-aGVHD) after unrelated cord blood transplantation (UCBT) . Methods: Fifty patients with IT-aGVHD who developed hormone resistance after UCBT from June 2016 to June 2023 at Anhui Provincial Hospital were collected to compare the effective and survival rates of IT-aGVHD treatment in the group with milder enteroscopic mucosal injury (27 cases, enteroscopic grading of Ⅰ and Ⅱ) and the group with more severe injury (23 cases, enteroscopic grading of Ⅲ and Ⅳ) and to retrospectively analyze the factors affecting patients' prognosis. Results: Patients in the mild and severe groups had an effective rate of 92.6% and 47.8% at 28 days after colonoscopy (P<0.001), 81.5% and 39.1% at 56 days after colonoscopy (P=0.002), with optimal effective rate of 92.6% and 65.2% (P=0.040), respectively, and the differences were statistically significant. The multifactorial analysis found that enteroscopic grading was an independent risk factor affecting the effective rate of IT-aGVHD treatment. The overall survival rate at 2 years after colonoscopy was 70.4% (95% CI 52.0% -88.8% ) and 34.8% (95% CI 14.8% -54.8% ) for patients in the mild and severe groups, respectively, and the difference was statistically significant (P=0.003). Multifactorial analysis revealed that enteroscopic grading, cytomegalovirus infection status, second-line treatment regimen, and patients' age were independent risk factors for survival. Conclusion: The treatment efficacy and prognosis of patients in the group with less severe enteroscopic injury (grades Ⅰ and Ⅱ) were better than those in the group with more severe injury (grades Ⅲ and Ⅳ) .

Additional yield of random biopsy in patients with inflammatory bowel disease: A systematic review and meta-analysis.

BACKGROUND & AIMS: There is limited clinical data regarding the additional yields of random biopsies during colorectal cancer surveillance in patients with inflammatory bowel disease. To assess the additional yield of RB, a systematic review and meta-analysis was conducted. METHODS: PubMed, Embase, Web of Science, and the Cochrane Library were searched for studies investigating the preferred colonoscopy surveillance approach for IBD patients. The additional yield, detection rate, procedure time, and withdrawal time were pooled. RESULTS: Thirty-seven studies (48 arms) were included in the meta-analysis with 9051 patients. The additional yields of RB were 10.34% in per-patient analysis, and 16.20% in per-lesion analysis. The detection rate were 1.31% and 2.82% in per-patient and per-lesion analysis, respectively. Subgroup analysis showed a decline in additional yields from 14.43% to 0.42% in the per-patient analysis and from 19.20% to 5.32% in the per-lesion analysis for studies initiated before and after 2011. In per-patient analysis, the additional yields were 4.83%, 10.29%, and 56.05% for PSC proportions of 0-10%, 10-30%, and 100%, respectively. The corresponding detection rates were 0.56%, 1.40%, and 19.45%. In the per-lesion analysis, additional yields were 11.23%, 21.06%, and 45.22% for PSC proportions of 0-10%, 10-30%, and 100%, respectively. The corresponding detection rates were 2.09%, 3.58%, and 16.24%. CONCLUSIONS: The additional yields of RB were 10.34% and 16.20% for per-patient and per-lesion analyses, respectively. Considering the decreased additional yields in studies initiated after 2011, and the influence of PSC, endoscopy centers lacking full HD equipment should consider incorporating RB in the standard colonoscopy surveillance for IBD patients, especially in those with PSC.

Visualization of cecal tumor by near-infrared laparoscopy and intraoperative colonoscopy.

BACKGROUND: In laparoscopic colorectal surgery, accurate localization of a tumor is essential for ensuring an adequate ablative margin. Therefore, a new method, near-infrared laparoscopy combined with intraoperative colonoscopy, was developed for visualizing the contour of a cecal tumor from outside of the bowel. The method was used after it was verified on a model that employed a silicone tube. CASE PRESENTATION: The patient was a 77-year-old man with a cecal tumor near the appendiceal orifice. Laparoscopy was used to clamp of the terminal ileum, and a colonoscope was then inserted through the anus to the cecum. The laparoscope in the normal light mode could not be used to identify the cecal tumor. However, a laparoscope in the near-infrared ray mode could clearly visualize the contour of the cecal tumor from outside of the bowel, and the tumor could be safely resected by a stapler. The histopathological diagnosis of the resected specimen was adenocarcinoma with an invasion depth of M and a clear negative margin. CONCLUSIONS: This is the first report of the laparoscopic detection of the contour of a cecal tumor from outside the bowel. This technique is useful and safe for contouring tumors in laparoscopic colorectal surgery and can be used in various surgeries that combine endoscopy and laparoscopy.

Cardiac Arrest Following GoLytely Consumption: A Potential Trigger for Hypovolemic Shock.

This case report presents a rare but severe complication of polyethylene glycol (PEG) used for colonoscopic bowel preparation. A 71-year-old male developed cardiac arrest secondary to hypovolemic shock following consumption of GoLytely. Despite being hemodynamically stable prior to ingestion, the patient experienced extreme weakness, dizziness, and orthostatic hypotension post-consumption. Evaluation ruled out other causes of arrest. While serious complications from PEG are rare, this case underscores the importance of vigilance. Further investigation is warranted to elucidate the relationship between PEG use and cardiac events and to identify potential risk factors for adverse outcomes associated with bowel preparation regimens.

A risk-prediction score about colorectal lesions based on the Chinese population of high-risk participants aged 50-65 years.

OBJECTIVES: The present study aims to develop an effective risk-prediction score (RPS) to improve screening efficiency and contribute to secondary prevention of colorectal cancer (CRC). STUDY DESIGN: Screening for colorectal lesions. METHODS: 14,398 high-risk individuals aged 50-65 years were included. The baseline characteristics of participants with and without colorectal lesions (CL) were compared using a Chi-squared test. The overall population was randomly split into a training set and a test set in the ratio of 80% and 20%. One-factor and multifactor logistic regression analyses were performed in the training set to construct the RPS (scores of 0-9.62). Area under curve (AUC) was calculated as an estimate of predictive performance using the receiver-operating characteristic (ROC) curve in the test set. RESULTS: In the study population, being male, advanced age, current or previous smoking, weekly alcohol consumption, high body mass index (BMI ≥24 kg/m2), and previously detected colonic polyp were associated with higher risk of CL. Compared to the low-risk group (0-2.31 points), the ORs and 95% confidence intervals (CIs) for the moderate-risk group (2.31-3.85 points) and high-risk group (3.85-8.42 points) were 1.58 (1.44, 1.73) and 2.52 (2.30, 2.76), respectively. For every 1-point increase in score, participants had a 27% increased risk of CL (OR:1.27, 95% CI: 1.24, 1.30). For participants with CL predicted by RPS, the area under the working characteristic curve was 0.61 (P < 0.001). CONCLUSION: Our RPS can quickly and efficiently identify multiple lesions of the colorectum. Combining RPS with existing screening strategies facilitates the identification of very high-risk individuals and may help to prevent CRC.

T1 colorectal cancer management in the era of minimally invasive endoscopic resection.

T1 colorectal cancer (CRC), defined by tumor invasion confined to the submucosa, has historically been managed by surgery. Improved understanding of recurrence and lymph node metastases risk, coupled with advances in endoscopic resection techniques, have led to an increasing capacity for organ-sparing local excision. Minimally invasive management of T1 CRC begins with optical evaluation of the lesion to diagnose invasive disease and quantify depth of invasion, which informs therapeutic decision making. Modality selection between various available endoscopic resection techniques depends upon lesion characteristics, technique risk-benefit profiles, and location-specific implications. Following endoscopic resection, established histopathology features determine the risk of recurrence and subsequent management including surveillance or adjuvant surgical excision. The management of non-operative candidates deviates from conventional recommendations with emerging treatment strategies in select populations.

Special stent for draining the abdominal abscess respectively from colon and duodenum: A case report.

BACKGROUND: Postoperative abdominal infections are an important and heterogeneous health challenge. Many samll abdominal abscesses are resolved with antibiotics, but larger or symptomatic abscesses may require procedural management. CASE SUMMARY: A 65-year-old male patient who suffered operation for the left hepatocellular carcinoma eight months ago, came to our hospital with recurrent abdominal pain, vomit, and fever for one month. Abdominal computed tomography showed that a big low-density dumbbell-shaped mass among the liver and intestine. Colonoscopy showed a submucosal mass with a fistula at colon of liver region. Gastroscopy showed a big rupture on the submucosal mass at the descending duodenum and a fistula at the duodenal bulb. Under colonoscopy, the brown liquid and pus were drained from the mass with "special stent device". Under gastroscopy, we closed the rupture of the mass with a loop and six clips for purse stitching at the descending duodenum, and the same method as colonoscopy was used to drain the brown liquid and pus from the mass. The symptom of abdominal pain, vomit and fever were relieved after the treatment. CONCLUSION: The special stent device could be effectively for draining the abdominal abscess respectively from colon and duodenum.

Large non-pedunculated colorectal polyp management: The elephant in the room.

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.

Tubular Adenoma Arising Within a Rectosigmoid Xanthoma: A Case Report.

Colonic xanthomas are a rare finding, particularly when combined with a tubular adenoma in a single polyp. While transformation to malignancy is not thought to be higher than that of a tubular adenoma alone, there is still concern as to the pathophysiology of xanthoma formation within the colon and what that may mean for patient outcomes. Here, we present a patient undergoing a routine screening colonoscopy with the removal of a rectosigmoid polyp consistent with xanthoma and tubular adenoma histopathology. Proper follow-up for identification of possible metabolic derangements and increased colonic surveillance is recommended to mitigate the risk of further xanthoma or adenocarcinoma formation.

Liver Disease as a Potential Risk Factor for Colorectal Cancer: A Community Hospital Experience.

BACKGROUND: Liver disease (LD) is a common pathology worldwide. Many patients remain asymptomatic and undiagnosed. Colorectal cancer (CRC) is a prevalent neoplasm and a leading cause of cancer-related deaths globally. Multiple studies suggest that inflammation in the liver could drive the initiation of colorectal cancer. METHODS: This five-year (2018-2022) case-control study included 274 patients diagnosed with CRC and adenomas at a community hospital in Houston, Texas. Each patient's medical record was reviewed for pre-existing LD, including steatosis, cirrhosis, primary biliary cirrhosis, and Hepatitis B and C infections. This study aims to investigate the association between LD and CRC risk and assess differences by gender, race, and ethnicity. The study cohort comprised 124 (45.3%) women and 150 (54.7%) men. Data were compared and analyzed using a Chi-squared test for independence and binomial logistic regression. A p-value of < 0.05 was considered statistically significant.  Results: Patients with LD had a two-fold increase in the odds of developing CRC compared to those without LD, in both univariate and multivariate analyses (OR 2.13 {95% CI 1.30-3.49}, p = 0.003 / OR 2.30 {95% CI 1.37-3.87}, p = 0.002, respectively). The chi-square test revealed that the association between CRC and LD was stronger in women than in men (p = 0.018 and p = 0.056, respectively). CONCLUSION: Our study establishes a positive correlation between LD and CRC development, suggesting LD is a potential risk factor for CRC, particularly in women. Future research directions include exploring the underlying mechanisms of this association, evaluating the utility of early CRC screening in individuals with LD, and assessing the impact of interventions targeting LD on CRC incidence and mortality.

Diagnostic Benefits and Surgical Implications of Methods for Tumor Localization in Sigmoid and Rectum Tumors.

(1) Background: In our study, we aimed to determine the accuracy rates of imaging methods for sigmoid, rectosigmoid colon, and rectum cancer. (2) Methods: Patients with tumors located in the rectosigmoid colon, sigmoid colon, and rectum who were operated on were included. Upon admission, we examined the patients' first diagnostic colonoscopies and their preoperative repeat control colonoscopies and computed tomography (CT) report. (3) Results: In this study, 23 patients (57.5%) were male. The overall accuracy rates were 80.0% (32/40) in colonoscopy, 65.0% (26/40) in preoperative CT, and 87.5% (35/40) in retro CT, and the differences among the examination methods were statistically significant (p = 0.049). The sensitivity levels decreased to 50.0% for colonoscopy and preoperative CT and 75.0% for retro CT in rectosigmoid colon tumors. In rectal tumors, the sensitivity levels were 75.0% in colonoscopy, 60.0% in preoperative CT, and 80.0% in retro CT. In two patients, the tumor location was given incorrectly, and postoperative pathological evaluations indicated T3N0 tumors; the initially planned treatment was thus changed to include radiotherapy in addition to chemotherapy in the postoperative period because the tumor was located in the middle rectum. (4) Conclusions: Accuracy in tumor localization in sigmoid, rectosigmoid, and rectum tumors still needs to be improved, which could be accomplished with prospective studies. CT evaluations for cancer localization in this patient group should be re-evaluated by a radiologist.

Long-term impact of artificial intelligence on colorectal adenoma detection in high-risk colonoscopy.

BACKGROUND: Improved adenoma detection rate (ADR) has been demonstrated with artificial intelligence (AI)-assisted colonoscopy. However, data on the real-world application of AI and its effect on colorectal cancer (CRC) screening outcomes is limited. AIM: To analyze the long-term impact of AI on a diverse at-risk patient population undergoing diagnostic colonoscopy for positive CRC screening tests or symptoms. METHODS: AI software (GI Genius, Medtronic) was implemented into the standard procedure protocol in November 2022. Data was collected on patient demographics, procedure indication, polyp size, location, and pathology. CRC screening outcomes were evaluated before and at different intervals after AI introduction with one year of follow-up. RESULTS: We evaluated 1008 colonoscopies (278 pre-AI, 255 early post-AI, 285 established post-AI, and 190 late post-AI). The ADR was 38.1% pre-AI, 42.0% early post-AI (P = 0.77), 40.0% established post-AI (P = 0.44), and 39.5% late post-AI (P = 0.77). There were no significant differences in polyp detection rate (PDR, baseline 59.7%), advanced ADR (baseline 16.2%), and non-neoplastic PDR (baseline 30.0%) before and after AI introduction. CONCLUSION: In patients with an increased pre-test probability of having an abnormal colonoscopy, the current generation of AI did not yield enhanced CRC screening metrics over high-quality colonoscopy. Although the potential of AI in colonoscopy is undisputed, current AI technology may not universally elevate screening metrics across all situations and patient populations. Future studies that analyze different AI systems across various patient populations are needed to determine the most effective role of AI in optimizing CRC screening in clinical practice.

Improving colorectal cancer screening programs.

In this editorial we comment on the article by Agatsuma et al published in the World Journal of Gastroenterology. They suggest policies for more effective colorectal screening. Screening is the main policy that has led to lower mortality rates in later years among the population that was eligible for screening. Colonoscopy is the gold standard tool for screening and has preventive effects by removing precancerous or early malignant polyps. However, colonoscopy is an invasive process, and fecal tests such as the current hemoglobin immunodetection were developed, followed by endoscopy, as the general tool for population screening, avoiding logistical and economic problems. Even so, participation and adherence rates are low. Different screening options are being developed with the idea that if people could choose between the ones that best suit them, participation in population-based screening programs would increase. Blood tests, such as a recent one that detects cell-free DNA shed by tumors called circulating tumor DNA, showed a similar accuracy rate to stool tests for cancer, but were less sensitive for advanced precancerous lesions. At the time when the crosstalk between the immune system and cancer was being established as a new hallmark of cancer, novel immune system-related biomarkers and information on patients' immune parameters, such as cell counts of different immune populations, were studied for the early detection of colorectal cancer, since they could be effective in asymptomatic people, appearing earlier in the adenoma-carcinoma development compared to the presence of fecal blood. sCD26, for example, detected 80.37% of advanced adenomas. To reach as many eligible people as possible, starting at an earlier age than current programs, the direction could be to apply tests based on blood, urine or salivary fluid to samples taken during routine visits to the primary health system.

[Intestinal Mantle Cell Lymphoma Complicated With Ileocecal Intussusception in Adults:Report of One Case].

Intestinal mantle cell lymphoma complicated with intussusception is rare in clinical practice,lacking specific clinical manifestations.CT and colonoscopy are helpful for the diagnosis of this disease,which need to be distinguished from colorectal cancer,Crohn's disease,and other pathological subtypes of lymphoma.The diagnosis still needs to be confirmed by pathological examination.This paper reports a case of intestinal mantle cell lymphoma complicated with ileocecal intussusception in an adult,aiming to improve the clinical and imaging doctors' understanding of this disease.

Early follow-up colonoscopy after colorectal cancer resection detects significant pathology.

BACKGROUND: Colonoscopy is a key component of surveillance after colorectal cancer (CRC) resection. Surveillance intervals for colonoscopy vary across the world, with a limited evidence-base to support guidelines. OBJECTIVE: To evaluate the timing and outcome of colonoscopies after CRC resection. METHODS: Retrospective cohort study on prospectively collected data. Included adult patients under surveillance following CRC resection. Patients with organ transplant, inflammatory bowel disease or colon cancer syndromes were excluded. The outcomes of the first (up to) three follow-up colonoscopies were audited and classified for presence of advanced neoplasia (advanced adenoma or adenocarcinoma). RESULTS: 980 patients underwent at least one follow-up colonoscopy with a median time to first colonoscopy of 12.4 months. The findings included 2.7% CRC and 13.2% advanced adenoma. Older age, stage IV disease, and synchronous cancers at surgery were significantly associated with a finding of advanced neoplasia at first colonoscopy. 562 patients underwent a second colonoscopy (median of 35 months after the first surveillance colonoscopy) with findings of 1.8% CRC and 11.4% advanced adenoma. Advanced adenoma on prior colonoscopy was associated with finding advanced neoplasia at the second colonoscopy. 288 patients underwent a third colonoscopy (median of 37 months from the preceding colonoscopy), with similar outcomes of advanced neoplasia being associated with advanced adenoma at the previous colonoscopy. 43 (4.4%) patients developed CRC whilst on surveillance. CONCLUSIONS: Timely surveillance after CRC resection is important for detecting advanced neoplasia, and prolonged intervals between colonoscopies in the early years after surgery should be avoided.