Dynamic Prediction of Advanced Colorectal Neoplasia in Inflammatory Bowel Disease

BACKGROUND & AIMS

Colonoscopic surveillance is recommended in patients with colonic inflammatory bowel disease (IBD) given their increased risk of colorectal cancer (CRC). We aimed to develop and validate a dynamic prediction model for the occurrence of advanced colorectal neoplasia (aCRN, including high-grade dysplasia and CRC) in IBD.

METHODS

We pooled data from 6 existing cohort studies from Canada, The Netherlands, the United Kingdom, and the United States. Patients with IBD and an indication for CRC surveillance were included if they underwent at least 1 follow-up procedure. Exclusion criteria included prior aCRN, prior colectomy, or an unclear indication for surveillance. Predictor variables were selected based on the literature. A dynamic prediction model was developed using a landmarking approach based on Cox proportional hazard modeling. Model performance was assessed with Harrell's concordance-statistic (discrimination) and by calibration curves. Generalizability across surveillance cohorts was evaluated by internal-external cross-validation.

RESULTS

The surveillance cohorts comprised 3731 patients, enrolled and followed-up in the time period from 1973 to 2021, with a median follow-up period of 5.7 years (26,336 patient-years of follow-up evaluation); 146 individuals were diagnosed with aCRN. The model contained 8 predictors, with a cross-validation median concordance statistic of 0.74 and 0.75 for a 5- and 10-year prediction window, respectively. Calibration plots showed good calibration. Internal-external cross-validation results showed medium discrimination and reasonable to good calibration.

CONCLUSIONS

The new prediction model showed good discrimination and calibration, however, generalizability results varied. Future research should focus on formal external validation and relate predicted aCRN risks to surveillance intervals before clinical application.

Smoking and colorectal neoplasia in patients with inflammatory bowel disease: Dose-effect relationship

BACKGROUND AND AIMS

Prior studies on the effect of smoking on the risk of colitis-associated colorectal neoplasia (CRN) have reported conflicting results. We aimed to further elucidate the association between smoking, including possible dose-effects, and the development of colorectal neoplasia in patients with inflammatory bowel disease (IBD).

METHODS

We performed a prospective multicenter cohort study including patients with colonic IBD enrolled in a surveillance program in four academic hospitals between 2011 and 2021. The effects of smoking status and pack-years at study entry on subsequent recurrent events of CRN (including indefinite, low- and high-grade dysplasia, and colorectal cancer [CRC]) were evaluated using uni- and multivariable Prentice, Williams, and Peterson total-time Cox proportional hazard models. Adjustment was performed for extensive disease, prior/index dysplasia, sex, age, first-degree relative with CRC, primary sclerosing cholangitis, and endoscopic inflammation.

RESULTS

In 501 of the enrolled 576 patients, at least one follow-up surveillance was performed after the study index (median follow-up 5 years). CRN occurred at least once in 105 patients. Ever smoking was not associated with recurrent CRN risk (adjusted hazard ratio [aHR] 1.04, 95% confidence interval [CI] 0.75-1.44), but an increasing number of pack-years was associated with an increased risk of recurrent CRN (aHR per 10 pack-years 1.17, 95% CI 1.03-1.32; p < 0.05). Separate analyses per IBD type did not reveal differences.

CONCLUSIONS

This study found that an increase in pack-years is associated with a higher risk of recurrent CRN in patients with IBD, independent of established CRN risk factors (NCT01464151).

Consecutive negative findings on colonoscopy during surveillance predict a low risk of advanced neoplasia in patients with inflammatory bowel disease with long-standing colitis: results of a 15-year multicentre, multinational cohort study

OBJECTIVES

Surveillance colonoscopy is thought to prevent colorectal cancer (CRC) in patients with long-standing colonic IBD, but data regarding the frequency of surveillance and the findings thereof are lacking. Our aim was to determine whether consecutive negative surveillance colonoscopies adequately predict low neoplastic risk.

DESIGN

A multicentre, multinational database of patients with long-standing IBD colitis without high-risk features and undergoing regular CRC surveillance was constructed. A 'negative' surveillance colonoscopy was predefined as a technically adequate procedure having no postinflammatory polyps, no strictures, no endoscopic disease activity and no evidence of neoplasia; a 'positive' colonoscopy was a technically adequate procedure that included at least one of these criteria. The primary endpoint was advanced colorectal neoplasia (aCRN), defined as high-grade dysplasia or CRC.

RESULTS

Of 775 patients with long-standing IBD colitis, 44% (n=340) had >1 negative colonoscopy. Patients with consecutive negative surveillance colonoscopies were compared with those who had at least one positive colonoscopy. Both groups had similar demographics, disease-related characteristics, number of surveillance colonoscopies and time intervals between colonoscopies. No aCRN occurred in those with consecutive negative surveillance, compared with an incidence rate of 0.29 to 0.76/100 patient-years (P=0.02) in those having >1 positive colonoscopy on follow-up of 6.1 (P25-P75: 4.6-8.2) years after the index procedure.

CONCLUSION

Within this large surveillance cohort of patients with colonic IBD and no additional high-risk features, having two consecutive negative colonoscopies predicted a very low risk of aCRN occurrence on follow-up. Our findings suggest that longer surveillance intervals in this selected population may be safe.

No Association Between Pseudopolyps and Colorectal Neoplasia in Patients With Inflammatory Bowel Diseases

BACKGROUND & AIMS

Patients with inflammatory bowel diseases who have postinflammatory polyps (PIPs) have an increased risk of colorectal neoplasia (CRN). European guidelines propose that patients with PIPs receive more frequent surveillance colonoscopies, despite limited evidence of this increased risk. We aimed to define the risk of CRN and colectomy in patients with inflammatory bowel diseases and PIPs.

METHODS

We conducted a multicenter retrospective cohort study of patients with inflammatory bowel diseases who underwent colonoscopic surveillance for CRN, from January 1997 through January 2017, at 5 academic hospitals and 2 large nonacademic hospitals in New York or the Netherlands. Eligible patients had confirmed colonic disease with duration of at least 8 years (or any duration, if they also had primary sclerosing cholangitis) and no history of advanced CRN (high-grade dysplasia or colorectal cancer) or colectomy. The primary outcome was occurrence of advanced CRN according to PIP status; secondary outcomes were occurrence of CRN (inclusive of low-grade dysplasia) and colectomy.

RESULTS

Of 1582 eligible patients, 462 (29.2%) had PIPs. PIPs were associated with more severe inflammation (adjusted odds ratio 1.32; 95% confidence interval [CI] 1.13-1.55), greater disease extent (adjusted odds ratio 1.92; 95% CI 1.34-2.74), and lower likelihood of primary sclerosing cholangitis (adjusted odds ratio 0.38; 95% CI 0.26-0.55). During a median follow-up period of 4.8 years, the time until development of advanced CRN did not differ significantly between patients with and those without PIPs. PIPs did not independently increase the risk of advanced CRN (adjusted hazard ratio 1.17; 95% CI 0.59-2.31). The colectomy rate was significantly higher in patients with PIPs (P = .01).

CONCLUSIONS

In a retrospective analysis of data from 2 large independent surveillance cohorts, PIPs were associated with greater severity and extent of colon inflammation and higher rates of colectomy, but were not associated with development of any degree of CRN. Therefore, intervals for surveillance should not be shortened based solely on the presence of PIPs.

High Risk of Advanced Colorectal Neoplasia in Patients With Primary Sclerosing Cholangitis Associated With Inflammatory Bowel Disease

BACKGROUND & AIMS

Patients with inflammatory bowel disease (IBD) and primary sclerosing cholangitis (PSC, termed PSC-IBD) are at increased risk for colorectal cancer, but their risk following a diagnosis of low-grade dysplasia (LGD) is not well described. We aimed to determine the rate of advanced colorectal neoplasia (aCRN), defined as high-grade dysplasia and/or colorectal cancer, following a diagnosis of indefinite dysplasia or LGD in this population.

METHODS

We performed a retrospective, longitudinal study of 1911 patients with colonic IBD (293 with PSC and 1618 without PSC) who underwent more than 2 surveillance colonoscopies from 2000 through 2015 in The Netherlands or the United States (9265 patient-years of follow-up evaluation). We collected data on clinical and demographic features of patients, as well as data from each surveillance colonoscopy and histologic report. For each surveillance colonoscopy, the severity of active inflammation was documented. The primary outcome was a diagnosis of aCRN during follow-up evaluation. We also investigated factors associated with aCRN in patients with or without a prior diagnosis of indefinite dysplasia or LGD.

RESULTS

Patients with PSC-IBD had a 2-fold higher risk of developing aCRN than patients with non-PSC IBD. Mean inflammation scores did not differ significantly between patients with PSC-IBD (0.55) vs patients with non-PSC IBD (0.56) (P = .89), nor did proportions of patients with LGD (21% of patients with PSC-IBD vs 18% of patients with non-PSC IBD) differ significantly (P = .37). However, the rate of aCRN following a diagnosis of LGD was significantly higher in patients with PSC-IBD (8.4 per 100 patient-years) than patients with non-PSC IBD (3.0 per 100 patient-years; P = .01). PSC (adjusted hazard ratio [aHR], 2.01; 95% CI, 1.09-3.71), increasing age (aHR 1.03; 95% CI, 1.01-1.05), and active inflammation (aHR, 2.39; 95% CI, 1.63-3.49) were independent risk factors for aCRN. Dysplasia was more often endoscopically invisible in patients with PSC-IBD than in patients with non-PSC IBD.

CONCLUSIONS

In a longitudinal study of almost 2000 patients with colonic IBD, PSC remained a strong independent risk factor for aCRN. Once LGD is detected, aCRN develops at a higher rate in patients with PSC and is more often endoscopically invisible than in patients with only IBD. Our findings support recommendations for careful annual colonoscopic surveillance for patients with IBD and PSC, and consideration of colectomy once LGD is detected.

Low Rate of Dysplasia Detection in Mucosa Surrounding Dysplastic Lesions in Patients Undergoing Surveillance for Inflammatory Bowel Diseases

BACKGROUND & AIMS

When dysplastic lesions are encountered during surveillance colonoscopy of patients with inflammatory bowel disease (IBD), guidelines recommend collection of additional biopsies from the surrounding mucosa to ensure the lesion has been adequately circumscribed. We aimed to determine the rate of dysplasia in mucosa biopsies collected from tissues surrounding dysplastic lesions during IBD surveillance.

METHODS

In a retrospective study, we collected endoscopy and pathology reports from 1065 patients undergoing colonoscopic surveillance for IBD from 2000 through 2015 at 3 centers in the Netherlands. We analyzed reports from all patients with dysplastic lesions from whom biopsies of surrounding mucosa were collected. Among 194 patients with 1 or more visible dysplastic lesions, mucosal biopsies were collected from tissues adjacent to 140 dysplastic lesions from 71 patients (63% male; 48% with ulcerative colitis, 42% with Crohn's disease, and 10% with indeterminate colitis).

RESULTS

The mean number of surrounding mucosa biopsies collected per lesion was 3.4 (range, 1-6). Dysplasia was detected in 7 biopsies surrounding 140 areas of dysplasia (5.0%) and 5 biopsies surrounding 136 areas of low-grade dysplasia (3.7%). Dysplasia in biopsies of surrounding mucosa could be observed during 5 of 87 white light endoscopies and during 2 of 53 chromoendoscopies. In patients with dysplasia in mucosa surrounding lesions of low-grade dysplasia, post-resection surveillance did not reveal high-grade dysplasia or colorectal cancer.

CONCLUSIONS

Dysplasia is detected in only 5% of biopsies collected from mucosa surrounding dysplastic lesions. This observation indicates that endoscopists accurately delineate the borders of dysplastic lesions during surveillance of patients with IBD. The lack of clinical consequences from routinely collecting biopsies from areas surrounding dysplastic lesions casts doubt on the usefulness and cost-effectiveness of this practice.

Clinical implications of low grade dysplasia found during inflammatory bowel disease surveillance: a retrospective study comparing chromoendoscopy and white-light endoscopy

Background and study aims Current guidelines recommend the use of pancolonic chromoendoscopy for surveillance of patients with inflammatory bowel disease (IBD). It is currently unknown whether low grade dysplasia (LGD) found using chromoendoscopy carries a similar risk of high grade dysplasia (HGD) or colorectal cancer (CRC) compared with LGD detected using white-light endoscopy (WLE). The aim of this study was to compare the risk of advanced neoplasia, a combined endpoint of HGD and CRC, during follow-up after detection of lesions containing LGD identified with either chromoendoscopy or WLE. Patients and methods A retrospective cohort was established to identify patients who underwent IBD surveillance for ulcerative colitis or colonic Crohn's disease between 2000 and 2014. Subgroups were identified, based on the endoscopic technique (standard definition resolution WLE, high definition resolution WLE or chromoendoscopy). LGD detected in random biopsies was considered invisible LGD. Patients were followed until detection of advanced neoplasia, colectomy, death, or the last known surveillance colonoscopy. Results Of 1065 patients undergoing IBD surveillance, 159 patients underwent follow-up for LGD, which was visible in 133 cases and invisible in 26 cases. On follow-up, five cases of HGD and five cases of CRC were detected. The overall incidence rate of advanced neoplasia was 1.34 per 100 patient-years with a median follow-up of 4.7 years and a median time to advanced neoplasia of 3.3 years. There were no significant differences in the incidence of advanced neoplasia between chromoendoscopy-detected and WLE-detected LGD. Conclusion Advanced neoplasia was found to develop infrequently after detection of LGD in patients undergoing endoscopic surveillance for IBD. LGD lesions detected with either chromoendoscopy or WLE carry similar risks of advanced neoplasia over time.

Incidence of Interval Colorectal Cancer Among Inflammatory Bowel Disease Patients Undergoing Regular Colonoscopic Surveillance

BACKGROUND & AIMS

Surveillance is recommended for patients with long-term inflammatory bowel disease because they have an increased risk of colorectal cancer (CRC). To study the effectiveness of surveillance, we determined the incidence of CRC after negative findings from surveillance colonoscopies (interval CRC).

METHODS

We collected data from 1273 patients with ulcerative colitis or Crohn's disease, enrolled in a surveillance program at 7 hospitals in The Netherlands, who underwent 4327 surveillance colonoscopies from January 1, 2000, through January 1, 2014. Patients were followed up from their first surveillance colonoscopy until the last surveillance colonoscopy, colectomy, or CRC. Factors that might have contributed to the occurrence of CRC were categorized as inadequate procedures (ie, inadequate bowel preparation), inadequate surveillance (CRC occurring outside the appropriate surveillance interval), or inadequate management of dysplasia (CRC diagnosed in the same colonic segment as a previous diagnosis of dysplasia). The remaining CRC cases were classified as true interval CRCs.

RESULTS

CRC was diagnosed in 17 patients (1.3%), with an incidence of 2.5 per 1000 years of follow-up evaluation. Factors that might account for the occurrence of CRC were identified in 12 patients (70%). These were inadequate colonoscopies in 4 patients (24%), inadequate surveillance intervals in 9 patients (53%), and inadequate management of dysplasia in 2 patients (12%). The remaining 5 cases of CRC (30%) were classified as true interval CRCs.

CONCLUSIONS

In a retrospective analysis of patients with inflammatory bowel disease participating in a surveillance program, the incidence of CRC was only 1%, which supports the implementation of longer surveillance intervals. However, the fact that 30% of CRC cases were interval cancers indicates the need for variable surveillance intervals based on risk factors for CRC.

Low interobserver agreement among endoscopists in differentiating dysplastic from non-dysplastic lesions during inflammatory bowel disease colitis surveillance

OBJECTIVES

During endoscopic surveillance in patients with longstanding colitis, a variety of lesions can be encountered. Differentiation between dysplastic and non-dysplastic lesions can be challenging. The accuracy of visual endoscopic differentiation and interobserver agreement (IOA) has never been objectified.

MATERIAL AND METHODS

We assessed the accuracy of expert and nonexpert endoscopists in differentiating (low-grade) dysplastic from non-dysplastic lesions and the IOA among and between them. An online questionnaire was constructed containing 30 cases including a short medical history and an endoscopic image of a lesion found during surveillance employing chromoendoscopy.

RESULTS

A total of 17 endoscopists, 8 experts, and 9 nonexperts assessed all 30 cases. The overall sensitivity and specificity for correctly identifying dysplasia were 73.8% (95% confidence interval (CI) 62.1-85.4) and 53.8% (95% CI 42.6-64.7), respectively. Experts showed a sensitivity of 76.0% (95% CI 63.3-88.6) versus 71.8% (95% CI 58.5-85.1, p = 0.434) for nonexperts, the specificity 61.0% (95% CI 49.3-72.7) versus 47.1% (95% CI 34.6-59.5, p = 0.008). The overall IOA in differentiating between dysplastic and non-dysplastic lesions was fair 0.24 (95% CI 0.21-0.27); for experts 0.28 (95% CI 0.21-0.35) and for nonexperts 0.22 (95% CI 0.17-0.28). The overall IOA for differentiating between subtypes was fair 0.21 (95% CI 0.20-0.22); for experts 0.19 (95% CI 0.16-0.22) and nonexpert 0.23 (95% CI 0.20-0.26).

CONCLUSION

In this image-based study, both expert and nonexpert endoscopists cannot reliably differentiate between dysplastic and non-dysplastic lesions. This emphasizes that all lesions encountered during colitis surveillance with a slight suspicion of containing dysplasia should be removed and sent for pathological assessment.

Low fecal calprotectin predicts sustained clinical remission in inflammatory bowel disease patients: a plea for deep remission

BACKGROUND AND AIMS

Mucosal healing has become the treatment goal in patients with ulcerative colitis (UC) and Crohn's disease (CD). Whether low fecal calprotectin levels and histological healing combined with mucosal healing is associated with a further reduced risk of relapses is unknown.

METHODS

Patients with CD, UC or inflammatory bowel disease-unclassified (IBD-U) scheduled for surveillance colonoscopy collected a stool sample prior to bowel cleansing. Only patients with mucosal healing (MAYO endoscopic score of 0) were included. Fecal calprotectin was measured using a quantitative enzyme-linked immunosorbent assay (R-Biopharm, Germany). Biopsies were obtained from four colonic segments, and histological disease severity was assessed using the Geboes scoring system. Patients were followed until the last outpatient clinic visit or the development of a relapse, which was defined as IBD-related hospitalization, surgery or step-up in IBD medication.

RESULTS

Of the 164 patients undergoing surveillance colonoscopy, 92 patients were excluded due to active inflammation or missing biopsies. Of the remaining 72 patients (20 CD, 52 UC or IBD-U), six patients (8%) relapsed after a median follow-up of 11 months (range 5-15 months). Median fecal calprotectin levels at baseline were significantly higher for patients who relapsed compared with patients who maintained remission (284 mg/kg vs. 37 mg/kg. p < 0.01). Fecal calprotectin below 56 mg/kg was found to optimally predict absence of relapse during follow-up with 64% sensitivity, 100% specificity, 100% negative predictive value and 20% positive predictive value. The presence or absence of active inflammation determined by Geboes cut-off score of 3.1 was less strongly associated with the risk of relapse (64% sensitivity, 33% specificity, 9% negative predictive value and 92% positive predictive value.

CONCLUSION

Low calprotectin levels identify IBD patients who remain in stable remission during follow-up.

A risk-profiling approach for surveillance of inflammatory bowel disease-colorectal carcinoma is more cost-effective: a comparative cost-effectiveness analysis between international guidelines

BACKGROUND

Colonoscopic surveillance for neoplasia is recommended for patients with inflammatory bowel disease (IBD)-related colitis. However, data on cost-effectiveness predate current international guidelines.

OBJECTIVE

To compare cost-effectiveness based on contemporary data between the surveillance strategies of the American Gastroenterological Association (AGA) and British Society of Gastroenterology (BSG).

DESIGN

We constructed a Markov decision model to simulate the clinical course of IBD patients.

SETTING

We compared the 2 surveillance strategies for a base case of a 40-year-old colitis patient who was followed for 40 years.

PATIENTS

AGA surveillance distinguishes 2 groups: a high-risk group with annual surveillance and an average-risk group with biannual surveillance. BSG surveillance distinguishes 3 risk groups with yearly, 3-year, or 5-year surveillance.

INTERVENTIONS

Patients could move from a no-dysplasia state with colonoscopic surveillance to 1 of 3 states for which proctocolectomy was indicated: (1) dysplasia/local cancer, (2) regional/metastasized cancer, or (3) refractory disease. After proctocolectomy, a patient moved to a no-colon state without surveillance.

MAIN OUTCOME MEASUREMENTS

Direct costs of medical care, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios.

RESULTS

BSG surveillance dominated AGA surveillance with $9846 per QALY. Both strategies were equally effective with 24.16 QALYs, but BSG surveillance was associated with lower costs because of fewer colonoscopies performed. Costs related to IBD, surgery, or cancer did not affect cost-effectiveness.

LIMITATIONS

The model depends on the accuracy of derived data, and the assumptions that were made to reflect real-life situations. Study conclusions may only apply to the U.S. health care system.

CONCLUSION

The updated risk-profiling approach for surveillance of IBD colorectal carcinoma by the BSG guideline appears to be more cost-effective.

Disease severity does not affect the interval between IBD diagnosis and the development of CRC: results from two large, Dutch case series

BACKGROUND

The increased risk of colorectal cancer (CRC) in patients with inflammatory bowel disease (IBD) is well established. The incidence of IBD-related CRC however, differs markedly between cohorts from referral centers and population-based studies. In the present study we aimed to identify characteristics potentially explaining these differences in two cohorts of patients with IBD-related CRC.

METHODS

PALGA, a nationwide pathology network and registry in The Netherlands, was used to search for patients with IBD-associated CRC between 1990 and 2006. Patients from 7 referral hospitals and 78 general hospitals were included. Demographic and disease specific parameters were collected retrospectively using patient charts.

RESULTS

A total of 281 patients with IBD-associated CRC were identified. Patients from referral hospitals had a lower median age at IBD diagnosis (26 years vs. 28 years (p=0.02)), while having more IBD-relapses before CRC diagnosis than patients from general hospitals (3.8 vs. 1.5 (p<0.01)). In patients from referral hospitals, CRC was diagnosed at a younger age (47 years vs. 51 years (p=0.01)). However, the median interval between IBD diagnosis and diagnosis of CRC was similar in both cohorts (19 years in referral hospitals vs. 17 years in general hospitals (p=0.13)).

CONCLUSIONS

IBD patients diagnosed with CRC treated in referral hospitals in The Netherlands are younger at both the diagnosis of IBD and CRC than IBD patients with CRC treated in general hospitals. Although patients from referral centers appeared to have a more severe course of IBD, the interval between IBD and CRC diagnosis was similar.

Endovascular treatment of a patient with an aneurysm of the proper hepatic artery and a duodenal fistula

Aneurysms of the proper hepatic artery comprise a rare but potentially dangerous entity for which treatment is performed both surgically and endovascularly. Covered stents are generally used for endovascular treatment of such aneurysms. When the aneurysm is contaminated due to an enteric fistula, however, use of a covered stent is considered inappropriate. This case report describes the endovascular repair of a proper hepatic artery aneurysm using overlapping bare metal stents after the patient was surgically treated for duodenal hemorrhage.