Age-Related Survival Differences in Patients With Inflammatory Bowel Disease-Associated Colorectal Cancer: A Population-Based Cohort Study

Epidemiology of Cancer in Older Adults: A Systematic Review

PURPOSE OF REVIEW

What are the prevalence, incidence and mortality rates of cancer among individuals aged 60 or older on a national, regional, and global scale? What factors affect differences in cancer survival between older and younger adults?

RECENT FINDINGS

The epidemiological literature on cancer in older adults, particularly in low- and middle-income countries (LMICs) and that focusing on the oldest adults, is expanding. These studies consistently show increasing global cancer incidence rates in older populations. Recent research also highlights a widening survival gap between middle-aged and older adults, with the stage at diagnosis being the primary driver. More research is needed to describe the cancer burden in older adults, especially focusing on the oldest population and LMICs, to better understand global healthcare challenges. Additionally, further exploring patient-related, clinical, and tumour-related factors which drive age-related survival differences could improve cancer outcomes in older adults.

Artificial intelligence for dysplasia detection during surveillance colonoscopy in patients with ulcerative colitis: A cross-sectional, non-inferiority, diagnostic test comparison study

BACKGROUND AND STUDY AIM

High-definition virtual chromoendoscopy, along with targeted biopsies, is recommended for dysplasia surveillance in ulcerative colitis patients at risk for colorectal cancer. Computer-aided detection (CADe) systems aim to improve colonic adenoma detection, however their efficacy in detecting polyps and adenomas in this context remains unclear. This study evaluates the CADe Discovery™ system's effectiveness in detecting colonic dysplasia in ulcerative colitis patients at risk for colorectal cancer.

PATIENTS AND METHODS

A prospective cross-sectional, non-inferiority, diagnostic test comparison study was conducted on ulcerative colitis patients undergoing colorectal cancer surveillance colonoscopy between January 2021 and April 2021. Patients underwent virtual chromoendoscopy (VCE) with iSCAN 1 and 3 with optical enhancement. One endoscopist, blinded to CADe Discovery™ system results, examined colon sections, while a second endoscopist concurrently reviewed CADe images. Suspicious areas detected by both techniques underwent resection. Proportions of dysplastic lesions and patients with dysplasia detected by VCE or CADe were calculated.

RESULTS

Fifty-two patients were included, and 48 lesions analyzed. VCE and CADe each detected 9 cases of dysplasia (21.4% and 20.0%, respectively; p=0.629) in 8 patients and 7 patients (15.4% vs. 13.5%, respectively; p=0.713). Sensitivity, specificity, positive and negative predictive values, and diagnostic accuracy for dysplasia detection using VCE or CADe were 90% and 90%, 13% and 5%, 21% and 2%, 83% and 67%, and 29.2% and 22.9%, respectively.

CONCLUSIONS

The CADe Discovery™ system shows similar diagnostic performance to VCE with iSCAN in detecting colonic dysplasia in ulcerative colitis patients at risk for colorectal cancer.

Obesity and early-onset colorectal cancer risk: emerging clinical evidence and biological mechanisms

Early-onset colorectal cancer (EOCRC) is defined as diagnosed at younger than 50 years of age and indicates a health burden globally. Patients with EOCRC have distinct risk factors, clinical characteristics, and molecular pathogenesis compared with older patients with CRC. Further investigations have identified different roles of obesity between EOCRC and late-onset colorectal cancer (LOCRC). Most studies have focused on the clinical characteristics of obesity in EOCRC, therefore, the mechanism involved in the association between obesity and EOCRC remains inconclusive. This review further states that obesity affects the carcinogenesis of EOCRC as well as its development and progression, which may lead to obesity-related metabolic syndrome, intestinal dysbacteriosis, and intestinal inflammation.

Pathology and Clinical Significance of Inflammatory Bowel Disease-Associated Colorectal Dysplastic Lesions

Timely diagnosis and effective management of colorectal dysplasia play a vital role in preventing mortality from colorectal cancer in patients with chronic inflammatory bowel disease. This review provides a contemporary overview of the pathologic and endoscopic classification of dysplasia in inflammatory bowel disease, their roles in determining surveillance and management algorithms, and emerging diagnostic and therapeutic approaches that might further enhance patient management.

Causal linkage between type 2 diabetes mellitus and inflammatory bowel disease: an integrated Mendelian randomization study and bioinformatics analysis

Background

Observational studies have indicated associations between type 2 diabetes mellitus (T2DM) and both colorectal cancer (CRC) and inflammatory bowel disease (IBD). However, the underlying causality and biological mechanisms between these associations remains unclear.

Methods

We conducted a bidirectional Mendelian randomization (MR) analysis employing summary statistics from genome-wide association studies involving European individuals. The inverse variance weighting (IVW) method was the primary method used to assess causality. Additionally, we applied MR Egger, Weighted median, Simple mode, and Weighted mode to evaluate the robustness of the results. Outliers were identified and eliminated using the MR-PRESSO, while the MR-Egger intercept was used to assess the horizontal pleiotropic effects of single nucleotide polymorphisms (SNPs). The heterogeneity was evaluated using the Cochrane Q test, and sensitivity analysis was performed using leave-one-out method. The F statistic was calculated to evaluate weak instrumental variable bias. Finally, a pilot bioinformatics analysis was conducted to explore the underlying biological mechanisms between T2DM and IBD/UC.

Results

The IVW results demonstrated that T2DM significantly reduced risks of IBD (OR=0.885, 95% CI: 0.818-0.958, P=0.002) and ulcerative colitis (UC) (OR=0.887, 95% CI: 0.812-0.968, P=0.007). Although the 95% CIs of MR Egger, Weighted median, Simple mode, and Weighted mode were broad, the majority of their estimates were consistent with the direction of IVW. Despite significant heterogeneity among SNPs, no horizontal pleiotropy was observed. The leave-one-out analysis showed that the causality remained consistent after each SNP was removed, underscoring the reliability of the results. Reverse MR analysis indicated that genetic susceptibility to both CRC and IBD had no significant effect on the relative risk of T2DM. Ten hub genes were identified, which mainly enriched in pathways including maturity onset diabetes of the young, thyroid cancer, gastric acid secretion, longevity regulating pathway, melanogenesis, and pancreatic secretion.

Conclusion

The presence of T2DM does not increase the risk of CRC or IBD. Moreover, T2DM might reduce risk of IBD, including UC. Conversely, the occurrence of CRC or IBD does not influence the risk of T2DM. The association between T2DM and IBD/UC may be related to the changes in multiple metabolic pathways and CTLA-4-mediated immune response.

Focal Cancer in Colitis

Colorectal cancer (CRC) is a known complication of inflammatory bowel disease (IBD). Widely accepted guidelines recommend that patients with ulcerative colitis diagnosed with CRC undergo total proctocolectomy with or without ileal pouch-anal anastomosis, and that patients with Crohn's disease and CRC undergo either total colectomy or proctocolectomy. These approaches are ideal for preventing synchronous and metachronous cancer, minimizing risk of refractory colitis requiring reoperation, and is the appropriate treatment for the vast majority of patients with IBD who are diagnosed with CRC and require surgical intervention. Segmental colectomy, however, may be considered in select patients with IBD and CRC, specifically in elderly patients with short disease duration, in patients with mild colitis identified preoperatively, in patients with high operative risk and prohibitive comorbidities, and in patients whose CRC appears to be sporadic as opposed to colitis-associated. Patients undergoing segmental resection must be closely surveilled postoperatively for dysplasia, recurrent cancer, and refractory colitis.

Colitis-Associated Colorectal Cancer Survival is Comparable to Sporadic Cases after Surgery: a Matched-Pair Analysis

BACKGROUND

Inflammatory bowel disease (IBD) confers an increased lifetime risk of colorectal cancer (CRC). The pathogenesis of colitis-associated CRC is considered distinct from sporadic CRC, but existing is mixed on long-term oncologic outcomes. This study aims to compare clinicopathological characteristics and survival between colitis-associated and sporadic CRC.

METHODS

Data was retrospectively extracted and analyzed from a single institutional database of patients with surgically resected CRC between 2004 and 2015. Patients with IBD were identified as having colitis-associated CRC. The remainder were classified as sporadic CRC. Propensity score matching was performed. Univariate and survival analyses were carried out to estimate the differences between the two groups.

RESULTS

Of 2275 patients included in this analysis, 65 carried a diagnosis of IBD (2.9%, 33 Crohn's disease, 29 ulcerative colitis, 3 indeterminate colitis). Average age at CRC diagnosis was 62 years for colitis-associated CRC and 65 for sporadic CRC. The final propensity score matched cohort consisted of 65 colitis-associated and 130 sporadic CRC cases. Patients with colitis-associated CRC were more likely to undergo total proctocolectomy (p < 0.01) and had higher incidence of locoregional recurrence (p = 0.026) compared to sporadic CRC patients. There were no significant differences in time to recurrence, tumor grade, extramural vascular invasion, perineural invasion, or rate of R0 resections. Overall survival and disease-free survival did not differ between groups. On multiple Cox regression, IBD diagnosis was not a significant predictor of survival.

CONCLUSIONS

Patients with colitis-associated CRC who undergo surgical resection have comparable overall and disease-free survival to patients with sporadic CRC.

Colorectal Cancer in Inflammatory Bowel Diseases: Epidemiology and Prevention: A Review

Simple Summary

Colorectal cancer (CRC) is one of the most serious potential complications of inflammatory bowel diseases (IBDs). The aging of patients affected by IBDs makes this issue a challenge that will increasingly be faced by clinicians in clinical practice, especially in light of the poorer prognosis for CRC in this group of people when compared with the general population. In this review, we summarize the current epidemiology, risk factors and various prevention strategies proposed for CRC in patients with IBDs.

Abstract

Colorectal cancer (CRC) is currently the third most frequent form of malignancy and the second in terms of mortality. Inflammatory bowel diseases (IBDs) are recognized risk factors for this type of cancer. Despite a worldwide increase in the incidence of CRC, the risk of CRC-related death in IBD patients has declined over time, probably because of successful surveillance strategies, the use of more effective drugs in the management of remission and improved indications to colectomy. This notwithstanding, CRC 5-year survival in patients with IBD is poorer than in the general population. This review provides a summary of the epidemiological features, risk factors and various prevention strategies proposed for CRC in IBD patients. Moreover, there is a special focus on reporting and highlighting the various prevention strategies proposed by the most important international scientific societies, both in terms of chemoprevention and endoscopic surveillance. Indeed, in conducting the analysis, we have given attention to the current primary, secondary and tertiary prevention guidelines, attempting to emphasize unresolved research and clinical problems related to this topic in order to improve diagnostic strategies and management.

Outcomes of colorectal cancer resection in patients with inflammatory bowel disease: a national population-based analysis in England and Wales

AIM

The aim was to compare early postoperative outcomes and 2-year cancer-specific mortality following colorectal cancer (CRC) resection in patients with and without inflammatory bowel disease (IBD) in England and Wales.

METHOD

Records for patients in the National Bowel Cancer Audit who had major CRC resection between April 2014 and December 2017 were linked to routinely collected hospital level administrative datasets and chemotherapy and radiotherapy datasets. Multivariable regression models were used to compare outcomes with adjustment for patient and tumour characteristics.

RESULTS

In all, 63 365 patients were included. 1285 (2.0%) had an IBD diagnosis: 839 (65.3%) ulcerative colitis, 435 (33.9%) Crohn's disease and 11 (0.9%) were indeterminate. IBD patients were younger, had more advanced cancer staging and a higher proportion of right-sided tumours. They also had a higher proportion of emergency resection, total/subtotal colectomy, open surgery and stoma formation at resection, with longer hospital admissions and higher rates of unplanned readmission and reoperation. Fewer rectal cancer patients with IBD received neoadjuvant radiotherapy (24.8% vs. 36.0%, P = 0.005) whilst similar proportions of Stage III colon cancer patients received adjuvant chemotherapy. Ninety-day postoperative mortality was similar, but unadjusted 2-year cancer-specific mortality was significantly higher in patients with IBD (subdistribution hazard ratio 1.35, 95% CI 1.18-1.55). Risk adjustment for patient and tumour factors reduced this association (adjusted subdistribution hazard ratio 1.22, 95% CI 1.05-1.43).

CONCLUSION

Patients with IBD and CRC are a distinct patient group who develop CRC at a younger age and undergo more radical surgery. They have worse cancer survival, with the difference in prognosis appearing after the early postoperative period.

Colorectal Cancer Screening in Inflammatory Bowel Diseases-Can Characterization of GI Microbiome Signatures Enhance Neoplasia Detection?

Current noninvasive methods for colorectal cancer (CRC) screening are not optimized for persons with inflammatory bowel diseases (IBDs), requiring patients to undergo frequent interval screening via colonoscopy. Although colonoscopy-based screening reduces CRC incidence in IBD patients, rates of interval CRC remain relatively high, highlighting the need for more targeted approaches. In recent years, the discovery of disease-specific microbiome signatures for both IBD and CRC has begun to emerge, suggesting that stool-based biomarker detection using metagenomics and other culture-independent technologies may be useful for personalized, early, noninvasive CRC screening in IBD patients. Here we discuss the utility of the stool microbiome as a noninvasive CRC screening tool. Comparing the performance of multiple microbiome-based CRC classifiers, including several multi-cohort meta-analyses, we find that noninvasive detection of colorectal adenomas and carcinomas from microbial biomarkers is an active area of study with promising early results.

Rectal Cancer Incidence is Low Following Rectal Diversion or Subtotal Colectomy for IBD: Results of a Population-based Study

BACKGROUND AND AIMS

Following subtotal colectomy or diversion for medically refractory inflammatory bowel disease [IBD], completion proctectomy has been recommended to reduce the risk of rectal cancer. However, this recommendation is based on low-quality evidence. Our objectives were to estimate the cumulative incidence of rectal cancer and evaluate if surveillance endoscopy reduces the risk of rectal cancer.

METHODS

We performed a population-based retrospective cohort study in Ontario, Canada, of all patients undergoing either subtotal colectomy or diversion for medically refractory IBD over 1991-2015. We excluded patients with a previous history of colorectal cancer or previous rectal resection, and those with <1 year of observation. We calculated the rate of incident rectal cancer using a competing risks model, and evaluated the effect of surveillance endoscopy on the rate of rectal cancer.

RESULTS

In all, 3700 patients were included with a median follow-up of 4.3 years. Of this cohort, 47% underwent rectal resection or restoration of gastrointestinal [GI] continuity during the observation period; 40 patients were diagnosed with rectal cancer, with a cumulative incidence of rectal cancer of 0.81% (95% confidence interval [CI] 0.53%, 1.20%) and 1.86% [95% CI 1.29%, 2.61%] at 10 and 20 years, respectively. Surveillance endoscopy was associated with a lower rate of rectal cancer (subhazard ratio [sHR] 0.37, 95% CI 0.16, 0.82, p = 0.014].

CONCLUSIONS

Among patients with a retained rectum following surgery for IBD, the risk of rectal cancer is low and appears to be lower when surveillance endoscopy is performed. Expectant management with surveillance endoscopy may be a reasonable alternative to completion proctectomy in selected patients.

Advances in Understanding Early-Onset Colorectal Cancer

Since the 1990s, the incidence of early-onset colorectal cancer (at <50 years of age) in the US has increased by more than 50%; similar increases have also been observed internationally. These increases are found particularly among individuals born during and after the 1960s, raising the possibility that the increased rates of early-onset colorectal cancer are attributable to changes in risk-factor patterns throughout successive generations. The reasons for these alarming epidemiologic patterns for early-onset colorectal cancer worldwide are only recently being investigated and major gaps in our knowledge remain. In the current issue of this journal, Arif and colleagues differentiated characteristics and outcomes of early-onset colorectal cancer in patients with the predisposing conditions of inflammatory bowel disease or hereditary genetic syndromes, compared with patients who have sporadic disease. Also, in this issue, Schumacher and colleagues investigated risk factors for early-onset colorectal adenocarcinoma in a nested case-control study among Kaiser Permanente Southern California (KPSC) health plan members. The research presented on characteristics and outcomes points to the importance of sporadic disease in the rise of early-onset colorectal cancer, while the research presented on risk factors points to the importance of obesity as a potential explanatory factor for this rise.See related articles by Arif et al., p. 1785 and by Schumacher et al., p. 1792.

Extent of Surgical Resection in Inflammatory Bowel Disease Associated Colorectal Cancer: a Population-Based Study

BACKGROUND

The extent of surgical resection in inflammatory bowel disease (IBD) patients who develop colorectal cancer (CRC) is not prescribed by guidelines. We aim to evaluate, at a population level, the association of extent of surgical resection with survival outcomes.

METHODS

Using a validated Ontario registry of Crohn's disease (CD) and ulcerative colitis (UC) patients, we identified patients who underwent colorectal cancer resection between 2007 and 2015. Patient, tumor, and treatment factors, including type of surgical resection, were collected. Resections were grouped as segmental, total colectomy, and proctocolectomy. Multivariable cox proportional hazard regression was performed to identify factors associated with survival, including extent of surgical resection.

RESULTS

Between 2007 and 2015, 84,694 patients had resections for CRC in the province of Ontario, 599 had ulcerative colitis (UC), and 366 had Crohn's disease (CD). Segmental resection was the most common operation performed and was more common in CD patients compared to UC (68% vs. 45.6%, p < 0.001). Five-year survival was 63.7% (95% CI 59.5-67.7) in UC patients and 57.5% (95% CI 51.9-62.7) in CD patients (p = 0.033). Multivariable analysis showed worse survival in patients undergoing total colectomy, compared to segmental resection [HR 1.70 (95% CI 1.31-2.21), p < 0.001]. There was no significant difference in survival between patients undergoing segmental resection and proctocolectomy [HR 0.99 (95% CI 0.78-1.27)]. This pattern was similar within the subtypes of IBD.

CONCLUSION

In the setting of IBD-associated CRC, segmental resection and proctocolectomy are associated with similar survival outcomes in both UC and CD patients. Prospective study is essential to explore these findings.

Hereditary and Inflammatory Bowel Disease-Related Early Onset Colorectal Cancer Have Unique Characteristics and Clinical Course Compared with Sporadic Disease

BACKGROUND

Early onset colorectal cancer (EoCRC), diagnosed in those <50 years old, is increasing in incidence. We sought to differentiate characteristics and outcomes of EoCRC in patients with sporadic disease or preexisting conditions.

METHODS

We evaluated 2,135 patients with EoCRC in a population-based cohort from the Canadian province of British Columbia. Patients were identified on the basis of presence of hereditary syndromes (n = 146) or inflammatory bowel disease (IBD; n = 87) and compared with patients with sporadic EoCRC (n = 1,902).

RESULTS

Proportions of patients with preexisting conditions were highest in the youngest decile of 18-29 (34.3%, P < 0.0001). Patients with sporadic EoCRC were older, more likely female, and had increased BMI (P < 0.05). IBD-related EoCRC had the highest rates of metastatic disease, poor differentiation, adverse histology, lymphovascular, and perineural invasion (P < 0.05). Survival was lower in patients with IBD (HR, 1.80; 95% CI, 1.54-3.13; P < 0.0001) and higher in hereditary EoCRC (HR, 0.47; 95% CI, 0.45-0.73; P < 0.0001) compared with sporadic. Prognosis did not differ between ulcerative colitis or Crohn's disease but was lower in those with undifferentiated-IBD (HR, 1.87; 95% CI, 1.01-4.05; P = 0.049). Lynch syndrome EoCRC had improved survival over familial adenomatous polyposis (HR, 0.31; 95% CI, 0.054-0.57; P = 0.0037) and other syndromes (HR, 0.43; 95% CI, 0.11-0.99; P = 0.049). In multivariate analysis controlling for prognostic factors, hereditary EoCRC was unchanged from sporadic; however, IBD-related EoCRC had worse overall survival (HR, 2.21; 95% CI, 1.55-3.16; P < 0.0001).

CONCLUSIONS

EoCRC is heterogenous and patients with preexisting conditions have different characteristics and outcomes compared with sporadic disease.

IMPACT

Prognostic differences identified here for young patients with colorectal cancer and predisposing conditions may help facilitate treatment planning and patient counseling.See related commentary by Hayes, p. xxx.

Stage at Diagnosis and Survival of Colorectal Cancer With or Without Underlying Inflammatory Bowel Disease: A Population-based Study

BACKGROUND

Inflammatory bowel disease [IBD] is a risk factor for colorectal cancer [CRC]. The aim of this study is to determine whether stage at diagnosis and survival differ between sporadic, ulcerative colitis [UC]- and Crohn's disease [CD]-related CRC.

METHODS

The English National Cancer Registry [NCIN], Hospital Episode Statistics [HES] and Office for National Statistics [ONS] datasets between 2000 and 2010 were linked, providing data on comorbidities, stage and date of death. A logistic regression model determined whether IBD was associated with an early [I/II] or late [III/IV] cancer. Cox regression analysis was used to examine survival differences between sporadic, UC- and CD-related cancers.

RESULTS

A total of 234 009 patients with CRC were included, of whom 985 [0.4%] and 1922 [0.8%] had CD and UC, respectively. UC, but not CD, was associated with an earlier stage compared with sporadic cancers (odds ratio [OR] 0.88, 95% confidence interval [CI] 0.79 to 0.98, p = 0.02). CD had a significantly worse survival compared with sporadic patients for stage II [HR = 1.71, CI 1.26 to 2.31 p <0.005] and III [1.53, CI 1.20 to 1.96, p <0.005] cancer. UC patients were associated with worse survival compared with the sporadic group for both stage III [1.38, CI 1.17 to 1.63, p <0.0005] and IV [1.13, CI 1.01 to 1.28, p = 0.04] cancer. After excluding sporadic patients, UC was associated with improved survival compared with CD [0.62, CI 0.43 to 0.90, p = 0.01] for stage II cancer.

CONCLUSIONS

Patients with IBD are diagnosed at an earlier stage but tend to have a worse survival compared with sporadic cases of CRC, in particular for nodal disease [stage III].Specifically, patients with CD-related CRC appear to fare worst in terms of survival compared with both the sporadic and UC groups.

Vitexin prevents colitis-associated carcinogenesis in mice through regulating macrophage polarization

BACKGROUND

Patients with inflammatory bowel disease are at increased risks of developing ulcerative colitis-associated colorectal cancer (CAC). Vitexin can suppress the proliferation of colorectal carcinoma cells in vitro orin vivo. However, different from colorectal carcinoma, CAC is more consistent with the transformation from inflammation to cancer in clinical chronic IBD patients. Therefore, we aim to investigated that vitexin whether possess benefic effects on CAC mice.

PURPOSE

We aimed to determine the beneficial effects of vitexin on CAC mice and reveal its underlying mechanism.

METHODS

The mouse CAC model was induced by Azoxymethane and dextran sodium sulfate (AOM/DSS) and CAC mice were treated with vitexin. At the end of this study, inflammatory cytokines of IL-1β, IL-6, TNF-α, IL-10 as well as nitric oxide (NO) were detected by kits after long-term treatment of vitexin. Pathological changes and macrophage polarization were determined by H&E and immunofluorescence in adjacent noncancerous tissue and carcinomatous tissue respectively of CAC mice.

RESULTS

Our results showed that oral administration of vitexin could significantly improve the clinical signs and symptoms of chronic colitis, relieve colon damage, regulate colonic inflammatory cytokines, as well as suppress tumor incidence and tumor burden. Interesting, vitexin caused a significant increase in serum level of NO and a higher content of NO in tumor tissue. In addition, vitexin significantly decreased M1 phenotype macrophages in the adjacent noncancerous tissue, while markedly up-regulated M1 macrophage polarization in the tumor tissue in the colon of CAC mice.

CONCLUSION

Vitexin can attenuate chronic colitis-associated carcinogenesis induced by AOM/DSS in mice and its protective effects are partly associated with its alternations in macrophage polarization in the inflammatory and tumor microenvironment .

The Link between Oral and Gut Microbiota in Inflammatory Bowel Disease and a Synopsis of Potential Salivary Biomarkers

The objective of this review is to provide recent evidence for the oral–gut axis connection and to discuss gastrointestinal (GI) immune response, inflammatory bowel disease (IBD) pathogenesis, and potential salivary biomarkers for determining GI health. IBD affects an estimated 1.3% of the US adult population. While genetic predisposition and environment play a role, abnormal immune activity and microbiota dysbiosis within the gastrointestinal tract are also linked in IBD pathogenesis. It has been inferred that a reduced overall richness of bacterial species as well as colonization of opportunistic bacteria induce systemic inflammation in the GI tract. Currently, there is supporting evidence that both oral and gut microbiota may be related to the development of IBD. Despite this, there are currently no curative therapies for IBD, and diagnosis requires samples of blood, stool, and invasive diagnostic imaging techniques. Considering the relative ease of collection, emerging evidence of association with non-oral diseases may imply that saliva microbiome research may have the potential for gut diagnostic or prognostic value. This review demonstrates a link between saliva and intestinal profiles in IBD patients, suggesting that saliva sampling has the potential to serve as a non-invasive biomarker for gut diseases such as IBD in the oral–gut axis.

Interval Colorectal Cancer in Inflammatory Bowel Disease: The Role of Guideline Adherence

BACKGROUND

Factors associated with interval colorectal cancer (CRC) development in the inflammatory bowel disease (IBD) population remain unclear.

AIMS

Among a cohort of patients with interval CRC, we aimed to evaluate IBD characteristics, colonoscopy quality indicators, and surveillance guideline adherence.

METHODS

We performed a retrospective review of IBD- and non-IBD-associated interval CRCs diagnosed between January 2007 and December 2014 within a large US healthcare system. We evaluated risk factors for CRC among patients with IBD. We assessed adherence to surveillance guidelines according to the American Society for Gastrointestinal Endoscopy (IBD surveillance) and the US Multi-Society Task Force on Colorectal Cancer (polyp surveillance). We compared colonoscopy quality measures between patients with and without IBD.

RESULTS

Among 5345 cases of colonic adenocarcinoma, we detected 15 IBD-associated cases of interval CRC and 230 non-IBD-associated cases of interval CRC. Compared to patients without IBD, IBD patients were younger (54.5 vs. 70.4 years; p < 0.0001) and experienced a shorter interval between index colonoscopy and CRC diagnosis (20.7 vs. 35.1 months; p = 0.0009). Fifty three percent (8/15) of interval CRCs in IBD patients were detected within surveillance guidelines. All IBD patients with interval CRC detected after guideline surveillance interval had high-risk features, including active inflammation, previous low-grade or indefinite dysplasia, multiple pseudopolyps on index colonoscopy, or a first-degree relative with CRC. There were no differences in colonoscopy quality measures between patients with and without IBD.

CONCLUSIONS

This study stresses the importance of strict short-interval surveillance for IBD patients with high-risk features, including active inflammation on index colonoscopy.