Rates and characteristics of postcolonoscopy colorectal cancer in the Swedish IBD population: what are the differences from a non-IBD population?

Type 2 diabetes mellitus and post-colonoscopy colorectal cancer: clinical and molecular characteristics and survival

PURPOSE

Studies suggest that patients with type two diabetes mellitus (T2D) may be at increased risk of post-colonoscopy colorectal cancer (PCCRC). We investigated clinical and molecular characteristics and survival of T2D patients with PCCRC to elucidate how T2D-related PCCRC may arise.

METHODS

We identified T2D patients with colorectal cancer (CRC) from 1995 to 2015 and computed prevalence ratios (PRs) comparing clinical and molecular characteristics of CRC in T2D patients with PCCRC vs. in T2D patients with colonoscopy-detected CRC (dCRC). We also followed T2D patients from the diagnosis of PCCRC/dCRC until death, emigration, or study end and compared mortality using Cox-proportional hazards regression models adjusted for sex, age, year of CRC diagnosis, and CRC stage.

RESULTS

Compared with dCRC, PCCRC was associated with a higher prevalence of proximal CRCs (54% vs. 40%; PR: 1.43, 95% confidence interval [CI] 1.27-1.62) in T2D patients. We found no difference between PCCRC vs. dCRC for CRC stage, histology, and mismatch repair status. The proportion of CRCs that could be categorized as PCCRC decreased over time. Within one year after CRC, 63% of PCCRC vs. 78% of dCRC patients were alive (hazard ratio [HR] 1.85 [95% CI 1.47-2.31]). Within five years after CRC, 44% of PCCRC vs. 54% of dCRC patients were still alive (HR 1.44 [95% CI 1.11-1.87]).

CONCLUSION

The increased prevalence of proximally located PCCRCs and the poorer survival may suggest overlooked colorectal lesions as a predominant explanation for T2D-related PCCRC, although altered tumor progression cannot be ruled out.

Management of Crohn's disease in Taiwan: consensus guideline of the Taiwan Society of Inflammatory Bowel Disease updated in 2023

Crohn's disease (CD) is a chronic, fluctuating inflammatory condition that primarily affects the gastrointestinal tract. Although the incidence of CD in Taiwan is lower than that in Western countries, the severity of CD presentation appears to be similar between Asia and the West. This observation indicates the urgency for devising revised guidelines tailored to the unique reimbursement system, and patient requirements in Taiwan. The core objectives of these updated guidelines include the updated treatment choices and the integration of the treat-to-target strategy into CD management, promoting the achievement of deep remission to mitigate complications and enhance the overall quality of life. Given the diversity in disease prevalence, severity, insurance policies, and access to medical treatments in Taiwan, a customized approach is imperative for formulating these guidelines. Such tailored strategies ensure that international standards are not only adapted but also optimized to local contexts. Since the inception of its initial guidelines in 2017, the Taiwan Society of Inflammatory Bowel Disease (TSIBD) has acknowledged the importance of continuous revisions for incorporating new therapeutic options and evolving disease management practices. The latest update leverages international standards and recent research findings focused on practical implementation within the Taiwanese healthcare system.

Post-colonoscopy colorectal cancer: A population-based cohort study of fecal occult blood test-positive colonoscopies

BACKGROUND

Data on post-colonoscopy colorectal cancers (PCCRCs) after fecal occult blood test (FOBT)-positive colonoscopies is scarce (guaiac-based (gFOBT) or fecal immunochemical test (FIT)).

AIMS

Evaluate the prevalence and characteristics of PCCRCs in the French gFOBT CRC screening program.

METHODS

Retrospective population-based cohort study of all gFOBT-positive colonoscopies performed among individuals aged 50-74 between 2003 and 2014 within the CRC screening program organized in the Haut-Rhin (Alsace, France). The main outcome was PCCRC-3y rate. Adenoma detection rates (ADRs) calculated on gFOBT-positive colonoscopies were compared to those calculated on FIT-positive colonoscopies performed by the same gastroenterologists.

RESULTS

Overall, 9106 gFOBT-positive colonoscopies performed by 36 gastroenterologists were included. Sixteen PCCRC-3y and 31 PCCRC-5y were diagnosed (68.8 % and 58.1 % were true interval PCCRCs respectively). The unadjusted PCCRC-3y rate was 2.4 % [95 % confidence interval (CI) 1.4 %-3.9 %]. The risk for PCCRC-5y was significantly higher when the gastroenterologist's ADR was <35 % compared to ≥35 % (HR 2.17 [95 %CI 1.19-3.93]). The mean absolute difference for ADR between gFOBT- and FIT-positive colonoscopies was 16.3 % in favor of FIT-positive colonoscopies.

CONCLUSION

PCCRC-3y prevalence was low, estimated at 2.4 %. We suggest that the minimum standard for ADR in gFOBT- and FIT-positive colonoscopies should be set at 35 % and 50 % to 55 % respectively, in the French screening program.

Treat-to-Target and Regular Surveillance of Inflammatory Bowel Disease Are Associated with Low Incidence and Early-Stage Detection of Malignancies: A Retrospective Cohort Study

Inflammatory bowel diseases (IBD), including ulcerative colitis (UC) and Crohn's disease (CD), increase the risk of malignancies, particularly colorectal cancer (CRC). We aimed to assess the incidence of malignancies in IBD patients managed using a treat-to-target approach and recommended surveillance. We retrospectively searched the electronic databases of two tertiary IBD centers in Milan from 2010 to 2019 for new diagnoses of malignancy in patients with pre-existing IBD. A total of 5239 patients with a follow-up of 19,820 years were included. In total, 71 malignancies were diagnosed in 70 patients (38 CD, 32 UC) with a mean age of 52.9 years, of whom 64% were former or active smokers. The annual incidence of all malignancies was 358 per 100,000 patient years (95% CI 275-444), and the standardized incidence rate (SIR) was 0.93 (95% CI 0.73-1.16). Gastrointestinal cancers were the most frequent (n = 17, 23.9%), in particular, CRC (n = 9), with an incidence of 45 per 100,000 (95% CI 15-74) and an SIR of 1.18 (95% CI 0.54-2.09). CRC occurred mainly in UC patients (6/8), while small bowel cancer was seen in CD patients (5/9). Melanoma and breast cancer (n = 8 each) were the most common non-GI cancers. No significant difference in incidence was found between CD or UC. Death occurred in nine patients (11%) and was due to cancer in eight of these cases, two of which were IBD-related. Most malignancies included in the surveillance were diagnosed at early (I-II) stages (20 vs. 4, p < 0.05). In patients with IBD, treat-to-target and strict surveillance were associated with a low incidence of cancer, similar to that of the general population, and the detection of malignancies at an early stage.

Post-colonoscopy rectal cancer in Swedish patients with Crohn's disease 2001-2015: a population-based case review study

OBJECTIVE

Post-colonoscopy colorectal cancer (PCCRC) is a key quality indicator of colonoscopy, and PCCRC rates are high in the IBD population. Rectal cancer, an important risk factor for PCCRC among patients with Crohn's disease (CD), has not previously been examined.

METHODS

Swedish adult patients with CD who underwent a colonoscopy within 36 months before a rectal cancer diagnosis between 2001 and 2015 were identified through the National Patient and Cancer registers. Their medical records were reviewed and a root-cause analysis and a sub-categorization according to the World Endoscopic Organization (WEO) were performed.

RESULTS

Of 24 patients with CD and PCCRC in the rectum, 79% were men and the median age was 50 (IQR 45-59) years. The median disease duration was 21.5 (IQR 19-30) years. The cancer was located in the distal 5 cm of the rectum in 63% of the cases. Retroversion in the rectum was reported in only one case. The most common plausible explanation for PCCRC was 'possible missed lesion, prior examination adequate' (63%); when adding retroversion in the rectum, instead 77% of examinations were considered negative but deemed as inadequate. The most common PCCRC sub-category was non-interval type C (54%) and B (37%). Among those with type C, 38% should have been included in surveillance according to present guidelines.

CONCLUSION

Better adherence to surveillance guidelines and more meticulous follow-up is warranted. The importance of performing rectal palpation and retroversion in the rectum is underscored and we suggest that this is included in the WEO algorithm.

DECIDE: Delphi Expert Consensus Statement on Inflammatory Bowel Disease Dysplasia Shared Management Decision-Making

BACKGROUND AND AIMS

Inflammatory bowel disease colitis-associated dysplasia is managed with either enhanced surveillance and endoscopic resection or prophylactic surgery. The rate of progression to cancer after a dysplasia diagnosis remains uncertain in many cases and patients have high thresholds for accepting proctocolectomy. Individualised discussion of management options is encouraged to take place between patients and their multidisciplinary teams for best outcomes. We aimed to develop a toolkit to support a structured, multidisciplinary and shared decision-making approach to discussions about dysplasia management options between clinicians and their patients.

METHODS

Evidence from systematic literature reviews, mixed-methods studies conducted with key stakeholders, and decision-making expert recommendations were consolidated to draft consensus statements by the DECIDE steering group. These were then subjected to an international, multidisciplinary modified electronic Delphi process until an a priori threshold of 80% agreement was achieved to establish consensus for each statement.

RESULTS

In all, 31 members [15 gastroenterologists, 14 colorectal surgeons and two nurse specialists] from nine countries formed the Delphi panel. We present the 18 consensus statements generated after two iterative rounds of anonymous voting.

CONCLUSIONS

By consolidating evidence for best practice using literature review and key stakeholder and decision-making expert consultation, we have developed international consensus recommendations to support health care professionals counselling patients on the management of high cancer risk colitis-associated dysplasia. The final toolkit includes clinician and patient decision aids to facilitate shared decision-making.

The 2023 Impact of Inflammatory Bowel Disease in Canada: Cancer and IBD

Cancer is a major cause of morbidity and mortality among people with inflammatory bowel disease (IBD). Intestinal cancers may arise as a complication of IBD itself, while extra-intestinal cancers may arise due to some of the immunosuppressive therapies used to treat IBD. Colorectal cancer (CRC) and small bowel cancer risks remain elevated among persons with IBD as compared to age-and sex-matched members of the general population, and the lifetime risk of these cancers is strongly correlated to cumulative intestinal inflammatory burden. However, the cumulative risk of cancer, even among those with IBD is still low. Some studies suggest that IBD-CRC incidence has declined over the years, possibly owing to improved treatment standards and improved detection and management of early neoplastic lesions. Across studies of extra-intestinal cancers, there are generally higher incidences of melanoma, hepatobiliary cancer, and lung cancer and no higher incidences of breast cancer or prostate cancer, with equivocal risk of cervical cancer, among persons with IBD. While the relative risks of some extra-intestinal cancers are increased with treatment, the absolute risks of these cancers remain low and the decision to forego treatment in light of these risks should be carefully weighed against the increased risks of intestinal cancers and other disease-related complications with undertreated inflammatory disease. Quality improvement efforts should focus on optimized surveillance of cancers for which surveillance strategies exist (colorectal cancer, hepatobiliary cancer, cervical cancers, and skin cancers) and the development of cost-effective surveillance strategies for less common cancers associated with IBD.

Post-colonoscopy cancer rate at a tertiary referral hospital in Australia: A data linkage analysis

BACKGROUND AND AIM

Colorectal cancer (CRC) diagnosed following a cancer-negative colonoscopy is termed as post-colonoscopy CRC (PCCRC). The World Endoscopy Organization has recently standardized the definition of PCCRC-3Y (CRC developing within 3 years of a cancer-negative colonoscopy). In the present study, we sought to assess PCCRC-3Y rate, perform root-cause analyses, and identify factors associated with development of PCCRC at a tertiary referral hospital in Australia.

METHODS

All patients undergoing colonoscopy from 2011 to 2018 were matched to a population-based cancer register. PCCRC-3Y rate was assessed for years 2011-2015. All PCCRC cases that developed within 6-48 months after a cancer-negative colonoscopy underwent root-cause analyses. Descriptive statistics were used to summarize data.

RESULTS

Among 17 828 patients undergoing colonoscopy, 367 CRC cases were diagnosed during the study period. This included nine PCCRC cases, which developed at a median of 14 months (range 7-34 months) after cancer-negative colonoscopy. The PCCRC-3Y rate for years 2011-2015 was 2.16% (95% CI 0.91-5.15). All nine PCCRC cases were moderately or poorly differentiated adenocarcinomas; seven of nine were early-stage CRC (stages I and II) and six of nine probably represented missed lesions at index colonoscopy despite an apparently adequate examination. History of inflammatory bowel disease (IBD) (odds ratio [OR] 21.9, 95% confidence interval [CI] 4.6-103.7, P < 0.001) and diverticulosis (OR 5.4, 95% CI 1.4-20.5, P = 0.01) were significantly associated with development of missed CRC.

CONCLUSIONS

In our tertiary referral colonoscopy cohort, PCCRC-3Y rate was 2.16% (95% CI 0.91-5.15). IBD and diverticulosis were significantly associated with risk of PCCRC. The majority of PCCRC lesions were likely missed at index colonoscopy, despite an apparently adequate examination.

Post-endoscopy colorectal cancer after colectomy in inflammatory bowel disease patients: a population-based register study

OBJECTIVES

Long-standing inflammatory bowel disease (IBD) colitis is an indication for endoscopic surveillance. Postcolonoscopy colorectal cancer (PCCRC), cancer detected after a negative colonoscopy, is a quality indicator for colonoscopy. In analogy with PCCRC, we aimed to assess postendoscopy CRC (PECRC) in individuals with IBD who had undergone colectomy.

METHODS

This register study included Swedish adults with an IBD diagnosis who had undergone colectomy and later were examined by either colonoscopy or sigmoidoscopy during 2001-2012. The final study population had a CRC diagnosis within 36 months of the index examination. Poisson regression was used to assess the relative risks (RR) of PECRC.

RESULTS

A total of 33 individuals, 12 with an ileorectal anastomosis and 21 with a rectal remnant, had a CRC diagnosis within 36 months of the index endoscopy. Eleven cancers were detected as CRCs, and 22 (67%) were PECRCs. Compared with individuals aged >70 years, individuals aged <30 years had an RR of 3.1 (P = 0.054) and individuals aged 30-50 years had a RR of 2.6 (P = 0.030). A longer interval between colectomy and index endoscopy (>10 vs. <10 years) was associated with a lower risk of PCCRC (RR = 0.5; P = 0.007). There was no significant difference between the risk for Crohn's disease vs. ulcerative colitis, or between ileorectal anastomosis and rectal remnant risks.

CONCLUSIONS

Continuous surveillance of IBD patients after colectomy is important. In the postcolectomy context, PECRC may be used as a quality indicator.

Characteristics of colorectal cancer and use of colonoscopy before colorectal cancer diagnosis among individuals with inflammatory bowel disease: A population-based study

Introduction

There are limited recent data on the characteristics of inflammatory bowel disease (IBD)-associated colorectal cancer (CRC) and the use of colonoscopy prior to CRC diagnosis among persons with IBD. We analyzed IBD-CRC characteristics, survival after IBD-CRC diagnosis and the use of colonoscopy prior to IBD-CRC diagnosis over time.

Methods

We identified individuals with and without IBD from the University of Manitoba IBD Epidemiology Database and CRC from linkage to the Manitoba Cancer Registry. We compared characteristics of IBD-CRC and sporadic-CRC using logistic regression and survival after CRC diagnosis using Cox regression analysis. We assessed rate and predictors of colonoscopy use 5 years to 6 months prior to IBD-CRC.

Results

1,262 individuals with CRC were included (212 IBD-CRC). IBD was associated with an increased risk of death after CRC diagnosis in 2004–2011 (HR 1.89; 95% CI 1.25–2.88) but not in 2012–2017 (HR = 1.002; CI 0.50–2.03). In the 5 years to 6 months prior to IBD-CRC (1989–2018), 51% underwent colonoscopy, which was very similar to IBD without CRC and contrasted to 9% among sporadic CRCs. Exposure to colonoscopy pre IBD-CRC remained stable through the study period (1989–2002 OR = 1.25; CI 0.77–2.01; 2003–2011 OR = 1.21; CI 0.56–1.70; reference 2012–2018). Exposure to colonoscopy pre-IBD-CRC was not associated with improved post-CRC survival.

Conclusion

The risk of death following CRC diagnosis is not impacted by a diagnosis of IBD in recent years. There is a very high proportion of post colonoscopy CRC among IBD-CRC, which has not changed over the years and needs detailed root-cause analysis and interventions.

Probiotics Interact With Lipids Metabolism and Affect Gut Health

Probiotics have attracted much attention due to their ability to modulate host intestinal microbe, participate in nutrient metabolism or immunomodulatory. Both inflammatory bowel disease (IBD) and bowel cancer are digestive system disease, which have become a global public health problem due to their unclear etiology, difficult to cure, and repeated attacks. Disturbed gut microbiota and abnormal lipid metabolism would increase the risk of intestinal inflammation. However, the link between lipid metabolism, probiotics, and IBD is unclear. In this review, we found that different lipids and their derivatives have different effects on IBD and gut microbes. ω-3 polyunsaturated fatty acids (PUFAs) docosahexaenoic acid, eicosapentaenoic acid, and their derivatives resolvin E1, resolvin D can inhibit oxidative stress and reactive oxygen species activate NFκB and MAPk pathway. While ω-6 PUFAs linoleic acid and arachidonic acid can be derived into leukotrienes and prostaglandins, which will aggravate IBD. Cholesterol can be converted into bile acids to promote lipid absorption and affect microbial survival and colonization. At the same time, it is affected by microbial bile salt hydrolase to regulate blood lipids. Low denstiy lipoprotein (LDL) is easily converted into oxidized LDL, thereby promoting inflammation, while high denstiy lipoprotein (HDL) has the opposite effect. Probiotics compete with intestinal microorganisms for nutrients or ecological sites and thus affect the structure of intestinal microbiota. Moreover, microbial short chain fatty acids, bile salt hydrolase, superoxide dismutase, glutathione, etc. can affect lipid metabolism and IBD. In conclusion, probiotics are directly or indirectly involved in lipids metabolism and their impact on IBD, which provides the possibility to explore the role of probiotics in improving gut health.

Characteristics and Survival of Patients With Inflammatory Bowel Disease and Postcolonoscopy Colorectal Cancers

BACKGROUND & AIMS

Postcolonoscopy colorectal cancers (PCCRCs) account for up to 50% of colorectal cancers (CRCs) in patients with inflammatory bowel disease (IBD). We investigated characteristics of IBD patients with PCCRC and their survival.

METHODS

We identified IBD patients (ulcerative colitis [UC] and Crohn's disease) diagnosed with CRC from 1995 to 2015. We defined PCCRC as diagnosed between 6 and 36 months, and detected CRC (dCRC) as diagnosed within 6 months after colonoscopy. We computed prevalence ratios comparing PCCRC vs dCRC and followed up patients from the diagnosis of PCCRC/dCRC until death, emigration, or study end. Mortality was compared using Cox proportional hazards regression models adjusted for sex, age, year of CRC diagnosis, and stage. The main analyses focused on patients with UC.

RESULTS

Among 23,738 UC patients undergoing colonoscopy, we identified 352 patients with CRC, of whom 103 (29%) had PCCRC. Compared with dCRC, PCCRC was associated with a higher prevalence of metastatic cancer (33% vs 20%; prevalence ratio, 1.64; 95% CI, 1.13-2.38), cancers showing mismatch repair deficiency (79% vs 56%; prevalence ratio, 1.40; 95% CI, 1.13-1.72), and proximally located cancers (54% vs 40%; prevalence ratio, 1.34; 95% CI, 1.06-1.69). The 1- and 5-year adjusted hazard ratios of death for PCCRC vs dCRC among UC patients were 1.29 (95% CI, 0.77-2.18) and 1.24 (95% CI, 0.86-1.79), respectively.

CONCLUSIONS

The characteristics of UC-related PCCRC suggest tumor biology as an important factor in the progression to cancer. However, the prognosis of PCCRC appears similar to that of dCRC.

c-MET immunohistochemical expression in sporadic and inflammatory bowel disease associated lesions

BACKGROUND

Post-colonoscopy colorectal cancer (CRC) rates for patients with inflammatory bowel disease (IBD) are unacceptably high. During colonoscopy, an intravenous fluorescent anti-c-MET probe may improve endoscopic detection of lesions. However, c-MET expression in IBD lesions is poorly defined, limiting translational studies.

AIM

To comprehensively define c-MET expression in sporadic and IBD-associated colorectal carcinogenesis.

METHODS

c-MET expression was immunohistochemically assessed in 319 formalin-fixed paraffin-embedded tissue specimens, colonoscopically or surgically retrieved between 1994-2017. Tissue included: 30 normal colorectal biopsies, 30 hyperplastic polyps (HP), 31 sessile serrated lesions (SSL), 55 tubular/tubulovillous adenomas with low (TA-LGD, n = 32) or high grade dysplasia (TA-HGD, n = 23), 26 sporadic (s)-CRCs, 16 quiescent IBD biopsies, 11 active/inflamed IBD biopsies, 18 IBD-associated dysplastic lesions (IBD-dys), and 102 IBD-CRCs. Expression was scored by two independent observers as: 0 = absent, 1 = weak, 2 = moderate or 3 = strong. Mann-Whitney U and Kruskal-Wallis tests were used to assess significance.

RESULTS

Positive epithelial cytoplasmic and membranous c-MET expression was observed in all tissues, indicating there is ubiquitous expression in the colorectum. c-MET expression was weak in normal colonic epithelium compared with each of the sporadic colonic lesions, including TA-LGD (P < 0.001), TA-HGD (P = 0.004), HP (P < 0.001), SSL (P < 0.001), and s-CRC (P < 0.001). Specifically, in sporadic (non-IBD) lesions, expression was stronger in TA-LGD compared with normal mucosa (P < 0.001), and stronger in s-CRC compared with TA-HGD (P = 0.004). However, there was no significant difference between TA-LGD and TA-HGD (P = 0.852). Further, there was no difference in c-MET expression between HP and SSL (P = 0.065). In IBD, expression was weaker in quiescent colonic mucosa compared with inflamed colonic mucosa (P < 0.001). There was no difference between inflamed colonic mucosa and IBD-dys (P = 0.512) or IBD-CRC (P = 0.296). However, expression was stronger in IBD-dys (P < 0.001) and IBD-CRC (P < 0.001) compared with quiescent IBD colonic mucosa.

CONCLUSION

The characterisation of c-MET expression suggest that an intravenous probe may improve the endoscopic detection of lesions in both non-IBD patients and IBD patients with quiescent disease.

Risk of a post-colonoscopy colorectal cancer in patients with type 2 diabetes: a Danish population-based cohort study

Objective

Prevalent type 2 diabetes (T2D) is associated with an increased risk of colorectal cancer and could impair the quality of bowel preparation for colonoscopy. This may in turn increase the risk of overlooked precancerous polyps and subsequent risk of post-colonoscopy colorectal cancer (PCCRC). We investigated whether patients with T2D are at increased risk of PCCRC compared with patients without T2D.

Design

We conducted a population-based cohort study of patients with T2D and without T2D undergoing colonoscopy in Denmark (1995–2015). We investigated the risk of PCCRC by calculating >6 to 36 months cumulative incidence proportions (CIPs) treating death and colectomy as competing risks. Using Cox proportional-hazards regression analyses, we also computed HRs of PCCRC, comparing patients with T2D and non-T2D. According to the World Endoscopy Organization guidelines, we calculated PCCRC 3-year rates to estimate the proportions of T2D and non-T2D CRC patients experiencing PCCRC.

Results

We identified 29 031 patients with T2D and 333 232 patients without T2D undergoing colonoscopy. We observed 250 PCCRCs among patients with T2D and 1658 PCCRCs among patients without T2D. The >6 to 36 months CIP after a first-time colonoscopy was 0.64% (95% CI 0.55% to 0.74%) for T2D and 0.36% (95% CI 0.34% to 0.38%) for patients without T2D. The HRs of PCCRC were 1.43 (95% CI 1.21 to 1.72) after a first-time colonoscopy and 1.18 (95% CI 0.75 to 1.85) after a second-time colonoscopy. The PCCRC 3-year rate was 7.9% for patients with T2D and 7.4% for patients without T2D.

Conclusion

T2D may be associated with an increased HR of PCCRC.

Extensive extraintestinal manifestations of ulcerative colitis in a patient initially suspected to have disseminated malignancy

A 44-year-old patient with known ulcerative colitis presented with abdominal pain and an abdominal mass. CT revealed cecal stranding, a mass at the left colonic flexure involving the pancreas and multiple lesions in the lungs, retroperitoneum and liver. The patient had also developed a scalp rash as well as impaired hearing. Biopsies from the abdominal mass and lungs revealed necrotic inflammation, and the clinical suspicion of malignancy could not be ruled out. After further examination, the patient was treated with high-dose steroids, which rapidly reduced the extraintestinal manifestations. Due to a persistent abscess formation at the left colonic flexure and pancreas, the patient was referred to our hospital for a total colectomy. Histology showed acute and chronic inflammation with cryptitis, indicating ulcerative colitis. Our case is a rare presentation of extensive extraintestinal disease in organs such as the lungs and liver, as well as necrotic mass formation at the colon site which mimicked malignancy.

Global colorectal cancer burden in 2020 and projections to 2040

As the third most common malignancy and the second most deadly cancer, colorectal cancer (CRC) induces estimated 1.9 million incidence cases and 0.9 million deaths worldwide in 2020. The incidence of CRC is higher in highly developed countries, and it is increasing in middle- and low-income countries due to westernization. Moreover, a rising incidence of early-onset CRC is also emerging. The large number of CRC cases poses a growing global public health challenge. Raising awareness of CRC is important to promote healthy lifestyle choices, novel strategies for CRC management, and implementation of global screening programs, which are critical to reducing CRC morbidity and mortality in the future. CRC is a heterogeneous disease, and its subtype affiliation influences prognosis and therapeutic response. An accurate CRC subtype classification system is of great significance for basic research and clinical outcome. Here, we present the global epidemiology of CRC in 2020 and projections for 2040, review the major CRC subtypes to better understand CRC molecular basis, and summarize current risk factors, prevention, and screening strategies for CRC.

Risk of a post-colonoscopy colorectal cancer diagnosis in patients with inflammatory bowel disease: a population-based cohort study

BACKGROUND : Post-colonoscopy colorectal cancers (PCCRCs) may account for up to 50 % of all colorectal cancers (CRCs) diagnosed in patients with inflammatory bowel disease (IBD). This may reflect a high colonoscopy frequency; however, evidence remains limited. METHODS : We conducted a cohort study of IBD and non-IBD patients undergoing colonoscopy. We calculated cumulative incidence proportions (CIPs) of PCCRC at 7-36 months after first-time and subsequent colonoscopies. We also computed crude and adjusted hazard ratios (HRs) of PCCRC, comparing IBD with non-IBD patients undergoing first-time and subsequent colonoscopies. Separate analyses were conducted for consecutive colonoscopies. We calculated 3-year rates of PCCRC to estimate the proportion of IBD and non-IBD CRC patients experiencing PCCRC. RESULTS : We observed 138 and 1909 PCCRCs among 34 688 IBD and 358 217 non-IBD patients who underwent colonoscopy. The CIP of PCCRC after first-time colonoscopy was 0.21 % (95 % confidence interval [CI] 0.17 %-0.27 %) for IBD patients and 0.37 % (95 %CI 0.35 %-0.39 %) for non-IBD patients. The adjusted HR of PCCRC after a first-time colonoscopy was 0.96 (95 %CI 0.75-1.22) and the adjusted HRs after subsequent colonoscopies had point estimates around 1.0. The 3-year PCCRC rate was 24.3 % (95 %CI 20.4 %-28.7 %) for IBD and 7.5 % (95 %CI 7.2 %-7.8 %) for non-IBD patients. CONCLUSIONS : Although PCCRCs accounted for a substantial proportion of all IBD-related CRCs, IBD patients had a low CIP of PCCRC. The elevated 3-year PCCRC rates may, among other factors, stem from the increased colonoscopy frequency in IBD patients.

Inflammatory bowel diseases and the risk of adverse health outcomes: Umbrella review of meta-analyses of observational studies

BACKGROUND AND AIM

Accumulating evidence indicates a plausible association between inflammatory bowel diseases and the risk of adverse health outcomes. However, the conclusions are inconsistent. We aimed to perform an umbrella review of meta-analyses to appraise and grade the evidence of the association between inflammatory bowel diseases and the risk of adverse health outcomes.

METHODS

Meta-analyses of observational studies that examined the associations between inflammatory bowel disease and the risk of adverse health outcomes in PubMed, EMBASE, and Web of Science were screened.

RESULTS

This umbrella review identified 25 meta-analyses, which yielded 123 effect estimates for 60 unique putative health outcomes. Patients with inflammatory bowel diseases had a higher risk of adverse health outcomes, including multiple cancers, cardiovascular disease, adverse pregnancy outcomes, adverse oral outcomes, and other adverse events. Moreover, inflammatory bowel diseases caused greater harm to health based on the presented evidence. However, none of the evidence was classified as "high" quality, only 15% was classified as "moderate," and 65% of outcomes were rated as "very low."

CONCLUSION

Patients with inflammatory bowel diseases had a higher risk of adverse health outcomes and further studies should be conducted to draw firmer conclusions.

Postcolonoscopy Colorectal Cancer in Sweden From 2003 to 2012: Survival, Tumor Characteristics, and Risk Factors

BACKGROUND & AIMS

The rate of postcolonoscopy colorectal cancer (PCCRC) is a measure of colonoscopy quality, but there are conflicting results from studies of survival times of patients with PCCRC. We assessed survival times of patients with PCCRC and characterized the microscopic and macroscopic features of postcolonoscopy colorectal tumors.

METHODS

We performed a population-based cohort study using data from a database in Sweden, on 458,937 colonoscopies (54.0% women) performed from 2003 through 2012. Rates of colorectal cancer within 3 years of a colonoscopy were calculated based on the World Endoscopy Organization guidelines. Risk factors were evaluated using Poisson regression analysis. We used Cox regression models and Kaplan-Meier analyses, stratified by sex, to assess conditional survival. Logistic regression models were used to evaluate features of postcolonoscopy colorectal tumors, including stage location (right, left, or rectum) differentiation grade (high or low), synchronous tumors, perineural growth, resection margins, and mucinous and vessel characteristics.

RESULTS

Within 36 months after a colonoscopy, there were 19,184 individuals who had received a diagnosis of CRC; 1384 of these were PCCRCs (7.2%). The proportion of individuals with PCCRC decreased from 9.4% in 2003 to 6.1% in 2012. The largest risk factors for PCCRC were a prior diagnosis of CRC (relative risk [RR], 3.31; 95% CI, 2.71-4.04), ulcerative colitis (RR, 5.44; 95% CI, 4.75-6.23), Crohn's disease (RR, 3.81; 95% CI, 2.98-4.87), and prior polypectomy (RR, 2.32; 95% CI, 1.97-2.72). Individuals with PCCRCs had shorter survival times than individuals with CRCs detected during the index colonoscopy. Multivariate hazard ratios for PCCRC were 2.75 for men (95% CI, 2.21-3.42) and 2.00 for women (95% CI, 1.59-2.52), respectively. Individuals with left-side PCCRC had shorter survival times than patients with CRC detected during the index colonoscopy. Postcolonoscopy colorectal tumors had increased odds of low differentiation grade (odds ratio, 1.27; 95% CI, 1.09-1.49) compared with colorectal tumors detected during the index colonoscopy.

CONCLUSIONS

In an analysis of colonoscopies in Sweden, the rate of PCCRCs decreased from 9.4% in 2003 to 6.1% in 2012. Diseases that require surveillance (such as prior colorectal neoplasms and inflammatory bowel diseases) are the largest risk factors for PCCRC. Patients with PCCRC have shorter survival times than patients with CRC detected during their initial colonoscopy-especially women and patients with left-side tumors.

A young woman who developed ascending colon cancer 2 years after the onset of ulcerative colitis

Guidelines recommend surveillance colonoscopy for patients with an ulcerative colitis (UC) duration of 8-10 years. We experienced a patient who had not undergone UC surveillance. A 35-year-old Japanese woman developed diarrhea and abdominal pain in January 2018 and was diagnosed with UC. She underwent medical therapy, and 18 months after onset of UC colonoscopy indicated that her UC activity was remission and showed no cancer lesions. Twenty-four months after onset, colonoscopy revealed a tumor in the ascending colon, and the biopsy revealed tubular adenocarcinoma. She had no family history of colorectal cancer. There were no findings of distant metastases or primary sclerosing cholangitis. Laparoscopy-assisted anus-preserving total proctocolectomy, the creation of a J-type ileal pouch, ileal pouch anal anastomosis, and the creation of an ileostomy were performed. The pathological report was type 3, 30 × 27-mm, adenocarcinoma (por2 > tub2), pT4a, Ly1a, V1a, budding grade 3, pN0, M0, Stage IIb. Some colitic cancers such as our patient's may not conform to the existing guidelines. When a colonoscopy is being performed for a UC patient, even if its timing is less < 8 years since the UC onset, suspicious lesions should be biopsied considering the possibility of cancer.

Causes of Post-Colonoscopy Colorectal Cancers Based on World Endoscopy Organization System of Analysis

BACKGROUND & AIMS

Postcolonoscopy colorectal cancer (PCCRC) is CRC diagnosed after a colonoscopy in which no cancer was found. A consensus article from the World Endoscopy Organization (WEO) proposed an approach for investigating and categorizing PCCRCs detected within 4 years of a colonoscopy. We aimed to identify cases of PCCRC and the factors that cause them, test the WEO system of categorization, quantify the proportion of avoidable PCCRCs, and propose a target rate for PCCRCs detected within 3 years of a colonoscopy that did not detect CRC.

METHODS

We performed a retrospective analysis of 107 PCCRCs identified at a single medical center in England from January 1, 2010, through December 31, 2017 using coding and endoscopy data. For each case, we reviewed clinical, pathology, radiology, and endoscopy findings. Using the WEO recommendations, we performed a root-cause analysis of each case, categorizing lesions as follows: possible missed lesion, prior examination adequate; possible missed lesion, prior examination inadequate; detected lesion, not resected; or likely incomplete resection of previously identified lesion. We determined whether PCCRCs could be attributed to the colonoscopist for technical or decision-making reasons, and whether the PCCRC was avoidable or unavoidable, based on the WEO categorization and size of tumor. The endoscopy reporting system provided performance data for individual endoscopists.

RESULTS

Of the PCCRCs identified, 43% were in high-risk patients (those with inflammatory bowel disease, previous CRC, previous multiple large polyps, or hereditary cancer syndromes) and 66% were located distal to the hepatic flexure. There was no correlation between postcolonoscopy colorectal tumor size and time to diagnosis after index colonoscopy. Bowel preparation was poor in 19% of index colonoscopies, and only 36% of complete colonoscopies had adequate photodocumentation of completion. Development of 73% of PCCRCs was determined to be affected by technical endoscopic factors, 17% of PCCRCs by administrative factors (follow-up procedures delayed/not booked by administrative staff), and 27% of PCCRCs by decision-making factors. Twenty-seven percent of PCCRCs were categorized as possible missed lesion, prior examination adequate; 58% as possible missed lesion, prior examination inadequate; 8% as detected lesion, not resected; and 7% as incomplete resection of previously observed lesion; 89% were deemed to be avoidable.

CONCLUSIONS

In a retrospective analysis of PCCRCs, using the WEO system of categorization, we found 43% to occur in high-risk patients; this might be reduced with more vigilant surveillance. Measures are needed to reduce technical, decision-making, and administrative factors. We found that 89% of PCCRCs may be avoidable. If half of avoidable PCCRCs could be prevented, the target rate of 2% for the PCCRC-3y (cancer diagnosed between 6 and 36 months after index colonoscopy) benchmark would be achievable.

Clinical Characteristics and Postoperative Outcomes of Patients Presenting With Upper Gastrointestinal Tract Crohn Disease

PURPOSE

Upper gastrointestinal (GI) tract involvement in Crohn disease (CD) is rare and effectiveness of surgical treatment is limited. The aim of this study was to evaluate characteristics and surgical outcomes of upper GI CD.

METHODS

Medical records of 811 patients who underwent intestinal surgery for CD between January 2006 and December 2015 at a single institution were reviewed. Upper GI CD was defined by involvement of the stomach to the fourth portion of duodenum, with or without concomitant small/large bowel CD involvement according to a modification of the Montreal classification.

RESULTS

We identified 24 patients (21 males, 3 females) who underwent surgery for upper GI CD. The mean age at diagnosis was 27 ± 12 years, the mean age at surgery was 33 ± 11 years, and the mean duration of CD was 73.6 ± 56.6 months. Fifteen patients (62.5%) had history of previous perianal surgery. Ten patients (41.7%) had duodenal or gastric stricture and 14 patients (58.3%) had penetrating fistula; patients with fistula were significantly more likely to develop complications (57.1% vs. 20.0%, P = 0.035). One patient with stricture had surgical recurrence. In seven patients with fistula, fistula was related to previous anastomosis. Patients with fistula had significantly longer hospital stays than those with stricture (16 days vs. 11 days, P = 0.01).

CONCLUSION

Upper GI CD is rare among CD types (2.96%). In patients with upper GI CD, penetrating fistula was associated with longer hospital stay and more complications.

Colorectal cancer in ulcerative colitis: a Scandinavian population-based cohort study

BACKGROUND

Ulcerative colitis (UC) is a risk factor for colorectal cancer (CRC). However, available studies reflect older treatment and surveillance paradigms, and most have assessed risks for incident CRC without taking surveillance and lead-time bias into account, such as by assessing CRC incidence by tumour stage, or stage-adjusted mortality from CRC. We aimed to compare both overall and country-specific risks of CRC mortality and incident CRC among patients with UC.

METHODS

In this population-based cohort study of 96 447 patients with UC in Denmark (n=32 919) and Sweden (n=63 528), patients were followed up for CRC incidence and CRC mortality between Jan 1, 1969, and Dec 31, 2017, and compared with matched reference individuals from the general population (n=949 207). Patients with UC were selected from national registers and included in the analysis if they had two or more records with a relevant International Classification of Disease in the patient register (in the country in question) or one such record plus a colorectal biopsy report with a morphology code suggestive of inflammatory bowel disease. For every patient with UC, we selected matched reference individuals from the total population registers of Denmark and Sweden, who were matched for sex, age, birth year, and place of residence. We used Cox regression to compute hazard ratios (HRs) for incident CRC, and for CRC mortality, taking tumour stage into account.

FINDINGS

During follow-up, we observed 1336 incident CRCs in the UC cohort (1·29 per 1000 person-years) and 9544 incident CRCs in reference individuals (0·82 per 1000 person-years; HR 1·66, 95% CI 1·57-1·76). In the UC cohort, 639 patients died from CRC (0·55 per 1000 person-years), compared with 4451 reference individuals (0·38 per 1000 person-years; HR 1·59, 95% CI 1·46-1·72) during the same time period. The CRC stage distribution in people with UC was less advanced (p<0·0001) than in matched reference individuals, but taking tumour stage into account, patients with UC and CRC remained at increased risk of CRC death (HR 1·54, 95% CI 1·33-1·78). The excess risks declined over calendar periods: during the last 5 years of follow-up (2013-17, Sweden only), the HR for incident CRC in people with UC was 1·38 (95% CI 1·20-1·60, or one additional case per 1058 patients with UC per 5 years) and the HR for death from CRC was 1·25 (95% CI 1·03-1·51, or one additional case per 3041 patients with UC per 5 years).

INTERPRETATION

Compared with those without UC, individuals with UC are at increased risk of developing CRC, are diagnosed with less advanced CRC, and are at increased risk of dying from CRC, although these excess risks have declined substantially over time. There still seems to be room for improvement in international surveillance guidelines.

FUNDING

The Swedish Medical Society, Karolinska Institutet, Stockholm County Council, Swedish Research Council, Swedish Foundation for Strategic Research, Independent Research Fund Denmark, Forte Foundation, Swedish Cancer Foundation.

Use of Phosphodiesterase 5 Inhibitors Is Associated With Lower Risk of Colorectal Cancer in Men With Benign Colorectal Neoplasms

BACKGROUND & AIMS

Phosphodiesterase 5 (PDE5) inhibitors have been proposed to have chemopreventative effects on colorectal cancer (CRC), although data are needed from population-based studies. We performed a nationwide cohort study to investigate the association between the use of PDE5 inhibitors and the risk of CRC in men with benign colorectal neoplasms.

METHODS

We identified men who received a diagnosis of benign colorectal neoplasm from July 2005 through March 2015 who were listed in the Swedish Hospital Discharge Register. We linked data with those from other national Swedish registers to obtain information about the prescription of PDE5 inhibitors and CRC diagnoses. Cox regression was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

A total of 4823 patients were prescribed PDE5 inhibitors during the study period; the incidence rate of CRC was 2.64 per 1000 person-years for men prescribed PDE5 inhibitors compared with 4.46 per 1000 person-years for men without a prescription. We found a significant negative association between PDE5 inhibitor use and risk of CRC (adjusted HR, 0.65; 95% CI, 0.49-0.85); the decreased risk of CRC was associated with an increased cumulative dose of PDE5 inhibitors (P = .003). PDE5 prescription was associated with greater reduction in risk of advanced-stage CRC (adjusted HR, 0.61; 95% CI, 0.37-1.00) than early-stage CRC (adjusted HR, 0.70; 95% CI, 0.50-0.98), but the difference was not significant.

CONCLUSIONS

In a nationwide population-based study of men with a diagnosis of benign colorectal neoplasm in Sweden, we found evidence that use of PDE5 inhibitors is associated with a reduced risk of CRC. Further studies are needed to confirm the observed association.