Interval colorectal cancers in inflammatory bowel disease: the grim statistics and true stories

Cancer Biology or Ineffective Surveillance? A Multicentre Retrospective Analysis of Colitis-Associated Post-Colonoscopy Colorectal Cancers

BACKGROUND AND AIMS

Inflammatory bowel disease [IBD] is associated with high rates of post-colonoscopy colorectal cancer [PCCRC], but further in-depth qualitative analyses are required to determine whether they result from inadequate surveillance or aggressive IBD cancer evolution.

METHODS

All IBD patients who had a colorectal cancer [CRC] diagnosed between January 2015 and July 2019 and a recent [<4 years] surveillance colonoscopy at one of four English hospital trusts underwent root cause analyses as recommended by the World Endoscopy Organisation to identify plausible PCCRC causative factors.

RESULTS

In total, 61% [n = 22/36] of the included IBD CRCs were PCCRCs. They developed in patients with high cancer risk factors [77.8%; n = 28/36] requiring annual surveillance, yet 57.1% [n = 20/35] had inappropriately delayed surveillance. Most PCCRCs developed in situations where [i] an endoscopically unresectable lesion was detected [40.9%; n = 9/22], [ii] there was a deviation from the planned management pathway [40.9%; n = 9/22], such as service-, clinician- or patient-related delays in acting on a detected lesion, or [iii] lesions were potentially missed as they were typically located within areas of active inflammation or post-inflammatory change [36.4%; n = 8/22].

CONCLUSIONS

IBD PCCRC prevention will require more proactive strategies to reduce endoscopic inflammatory burden, and to improve lesion optical characterization, adherence to recommended surveillance intervals, and patient acceptance of prophylactic colectomy. However, the significant proportion appearing to originate from non-adenomatous-looking mucosa which fail to yield neoplasia on biopsy yet display aggressive cancer evolution highlights the limitations of current surveillance. Emerging molecular biomarkers may play a role in enhancing cancer risk stratification in future clinical practice.

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.

Performance measures for colonoscopy in inflammatory bowel disease patients: European Society of Gastrointestinal Endoscopy (ESGE) Quality Improvement Initiative

The European Society of Gastrointestinal Endoscopy (ESGE) presents a short list of performance measures for colonoscopy in inflammatory bowel disease (IBD) patients. Current performance measures for colonoscopy mainly focus on detecting (pre)malignant lesions. However, these performance measures are not relevant for all colonoscopy indications in IBD patients. Therefore, our aim was to provide endoscopy services across Europe and other interested countries with a tool for quality monitoring and improvement in IBD colonoscopy. Eight key performance measures and one minor performance measure were recommended for measurement and evaluation in daily endoscopy practice.

Differentially Deregulated MicroRNAs as Novel Biomarkers for Neoplastic Progression in Ulcerative Colitis

INTRODUCTION

Colorectal cancer (CRC) is a potentially life-threatening complication of long-standing ulcerative colitis (UC). MicroRNAs (miRNA) are epigenetic regulators that have been involved in the development of UC-associated CRC. However, their role as potential mucosal biomarkers of neoplastic progression has not been adequately studied.

METHODS

In this study, we analyzed the expression of 96 preselected miRNAs in human formalin-fixed and paraffin-embedded tissue of 52 case biopsies (20 normal mucosa, 20 dysplasia, and 12 UC-associated CRCs) and 50 control biopsies (10 normal mucosa, 21 sporadic adenomas, and 19 sporadic CRCs) by using Custom TaqMan Array Cards. For validation of deregulated miRNAs, we performed individual quantitative real-time polymerase chain reaction in an independent cohort of 50 cases (13 normal mucosa, 25 dysplasia, and 12 UC-associated CRCs) and 46 controls (7 normal mucosa, 19 sporadic adenomas, and 20 sporadic CRCs).

RESULTS

Sixty-four miRNAs were found to be differentially deregulated in the UC-associated CRC sequence. Eight of these miRNAs were chosen for further validation. We confirmed miR-31, -106a, and -135b to be significantly deregulated between normal mucosa and dysplasia, as well as across the UC-associated CRC sequence (all P < 0.01). Notably, these miRNAs also confirmed to have a significant differential expression compared with sporadic CRC (all P < 0.05).

DISCUSSION

UC-associated and sporadic CRCs have distinct miRNA expression patterns, and some miRNAs indicate early neoplastic progression.

Possible Earlier Diagnosis of Ulcerative Colitis-Associated Neoplasia: A Retrospective Analysis of Interval Cases during Surveillance

Background: Early detection of ulcerative colitis-associated neoplasia (UCAN) is often difficult. The aim of this study was to clarify the morphology of initial UCAN. Methods: White-light colonoscopy images obtained within the 2 years before UCAN diagnosis were retrospectively reviewed. The primary endpoint was the frequency of visible or invisible neoplasia on the endoscopic images before UCAN diagnosis. The secondary endpoints were comparisons of (1) visible or invisible neoplasia on initial endoscopic images of early-stage and advanced cancers, (2) the clinical backgrounds of patients in whom neoplasia was visible or invisible on initial endoscopic images, and (3) the clinical backgrounds of patients with distinct and indistinct UCAN borders. Results: Of the 27 UCAN lesions (11 early-stage; 16 advanced-stage), 25.9% (n = 7) were initially visible and 74.1% (n = 20) were invisible. The mean interval between the last surveillance colonoscopy and UCAN diagnosis was 14.5 ± 6.7 months. Of early-stage cancers, 18.2% (n = 2) were visible and 81.8% (n = 9) were invisible. Of advanced-stage cancers, 31.3% (n = 5) were visible and 68.8% (n = 11) were invisible. Invisible lesions were significantly more common in the rectum (p = 0.011) and tended to be more common in patients with inflammation and left-sided colitis (p = 0.084, p = 0.068, respectively). Patients with indistinct UCAN borders were significantly more likely to present with inflammation than those with distinct UCAN borders (p = 0.021). Conclusion: More careful surveillance is needed because rectum lesions and inflammation are difficult to identify as neoplasia even within the 2 years before a UCAN diagnosis.

Mutational Analysis Identifies Therapeutic Biomarkers in Inflammatory Bowel Disease-Associated Colorectal Cancers

Purpose: Inflammatory bowel disease-associated colorectal cancers (IBD-CRC) are associated with a higher mortality than sporadic colorectal cancers. The poorly defined molecular pathogenesis of IBD-CRCs limits development of effective prevention, detection, and treatment strategies. We aimed to identify biomarkers using whole-exome sequencing of IBD-CRCs to guide individualized management.Experimental Design: Whole-exome sequencing was performed on 34 formalin-fixed paraffin-embedded primary IBD-CRCs and 31 matched normal lymph nodes. Computational methods were used to identify somatic point mutations, small insertions and deletions, mutational signatures, and somatic copy number alterations. Mismatch repair status was examined.Results: Hypermutation was observed in 27% of IBD-CRCs. All hypermutated cancers were from the proximal colon; all but one of the cancers with hypermutation had defective mismatch repair or somatic mutations in the proofreading domain of DNA POLE Hypermutated IBD-CRCs had increased numbers of predicted neo-epitopes, which could be exploited using immunotherapy. We identified six distinct mutation signatures in IBD-CRCs, three of which corresponded to known mechanisms of mutagenesis. Driver genes were also identified.Conclusions: IBD-CRCs should be evaluated for hypermutation and defective mismatch repair to identify patients with a higher neo-epitope load who may benefit from immunotherapies. Prospective trials are required to determine whether IHC to detect loss of MLH1 expression in dysplastic colonic tissue could identify patients at increased risk of developing IBD-CRC. We identified mutations in genes in IBD-CRCs with hypermutation that might be targeted therapeutically. These approaches would complement and individualize surveillance and treatment programs. Clin Cancer Res; 24(20); 5133-42. ©2018 AACR.

World Endoscopy Organization Consensus Statements on Post-Colonoscopy and Post-Imaging Colorectal Cancer

BACKGROUND & AIMS

Colonoscopy examination does not always detect colorectal cancer (CRC)- some patients develop CRC after negative findings from an examination. When this occurs before the next recommended examination, it is called interval cancer. From a colonoscopy quality assurance perspective, that term is too restrictive, so the term post-colonoscopy colorectal cancer (PCCRC) was created in 2010. However, PCCRC definitions and methods for calculating rates vary among studies, making it impossible to compare results. We aimed to standardize the terminology, identification, analysis, and reporting of PCCRCs and CRCs detected after other whole-colon imaging evaluations (post-imaging colorectal cancers [PICRCs]).

METHODS

A 20-member international team of gastroenterologists, pathologists, and epidemiologists; a radiologist; and a non-medical professional met to formulate a series of recommendations, standardize definitions and categories (to align with interval cancer terminology), develop an algorithm to determine most-plausible etiologies, and develop standardized methodology to calculate rates of PCCRC and PICRC. The team followed the Appraisal of Guidelines for Research and Evaluation II tool. A literature review provided 401 articles to support proposed statements; evidence was rated using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) system. The statements were voted on anonymously by team members, using a modified Delphi approach.

RESULTS

The team produced 21 statements that provide comprehensive guidance on PCCRCs and PICRCs. The statements present standardized definitions and terms, as well as methods for qualitative review, determination of etiology, calculation of PCCRC rates, and non-colonoscopic imaging of the colon.

CONCLUSIONS

A 20-member international team has provided standardized methods for analysis of etiologies of PCCRCs and PICRCs and defines its use as a quality indicator. The team provides recommendations for clinicians, organizations, researchers, policy makers, and patients.

Incidence and Classification of Postcolonoscopy Colorectal Cancers in Inflammatory Bowel Disease: A Dutch Population-Based Cohort Study

BACKGROUND AND AIMS

Patients with inflammatory bowel disease [IBD] colitis are at increased risk for colorectal cancer [CRC]. We examined the proportion and most likely aetiology of potentially preventable postcolonoscopy CRCs [PCCRCs] in a population-based cohort. Furthermore, adherence to IBD surveillance guidelines was evaluated in both PCCRCs and the remainder of prevalent CRCs.

METHODS

All IBD patients diagnosed from 1991 to 2011 in the South Limburg region of The Netherlands [i.e. IBDSL cohort] were included. CRC cases were cross-checked with the Dutch pathology database and cancer registry. PCCRCs were defined as cancers diagnosed within 6-60 months after a colonoscopy and were classified as attributable to 'inappropriate surveillance interval', 'inadequate bowel examination', 'incomplete resection', 'missed lesion' or 'newly developed cancer'.

RESULTS

Twenty CRC cases were identified during 25,931 patient years of follow-up in 2,801 patients. The proportion of PCCRCs was 45.0%. Of these, 55.6% could be considered a 'missed lesion', while other possible aetiologies occurred only once. Considering both PCCRCs [n=9] and prevalent CRCs [n=11], ten were detected after publication of the surveillance guideline, but only three patients were enrolled. Moreover, 6 CRCs [30.0%] were detected before the recommended start of surveillance.

CONCLUSIONS

In the IBDSL cohort, 45.0% of all CRCs were considered to be PCCRCs, mainly classified as missed lesions. Additionally, a large proportion of CRCs in our cohort were observed before a surveillance endoscopy was performed. Therefore, stringent adherence to IBD surveillance guidelines, improving endoscopy techniques and adjusting the surveillance program may lead to a decrease in CRC incidence.

Interval colorectal cancer: a challenging field in colorectal cancer

Accumulated evidence has shown that colonoscopy may not be a perfect tool in screening and reducing the incidence of the colorectal cancer (CRC), because interval CRC (I-CRC), a specific subgroup of CRCs, has been challenging the traditional detection technology in recent years. I-CRC is accounting for an increasing proportion in CRCs. However, the effective procedures to prevent and supervise I-CRC need to be explored. In this review, we summarized the incidence, causes, risk factors, characteristics and management of I-CRC. It would promote the awareness of the special value in the education and training for the gastroenterologists, which plays an important role in conquering CRC.

Modern Endoscopic Imaging in Diagnosis and Surveillance of Inflammatory Bowel Disease Patients

Endoscopy remains the most important diagnostic and monitoring modality in the management of inflammatory bowel disease. Advances in imaging have progressively added new tools into the armamentarium of endoscopists with the goal of more accurate, sensitive, and accessible visual diagnoses for the benefit of patients with gastrointestinal diseases. Here, we review the relevant literature regarding commonly used endoscopic techniques (dye-based and digital chromoendoscopy, high-definition endoscopy, capsule endoscopy, and endosonography), as well as advanced and experimental technologies (full-spectrum endoscopy, endocytoscopy, autofluorescence, laser endoscopy, and endomicroscopy, including molecular imaging), applicable to inflammatory bowel diseases and emerging for implementation into everyday practice. Additionally, we discuss future directions and techniques as candidates for a superior inflammation imaging in the diagnosis and prediction of therapeutic response.

Post-colonoscopy colorectal cancers in Sweden: room for quality improvement

OBJECTIVE

Post-colonoscopy colorectal cancer (PCCRC), a cancer occurring within a short interval of a colonoscopy, might be partly explained as missed or incompletely resected lesions. Associated risk factors are age, sex, comorbidity, cancer location, and colonoscopy volume. There is a gap in the knowledge of prevalence of PCCRC and the impact of different risk factors in Sweden.

METHODS

This is a retrospective population-based observational cohort study of the colonoscopies performed on adults during the years 2001-2010 that were identified from Swedish health registers. The rate of PCCRC (diagnosed 6-36 months after the first colonoscopy) was defined as the number of PCCRCs divided by the number of colorectal cancers (CRC) in the interval of 0-36 months. Univariate and multivariate Poisson regression analyses examined associations with PCCRC.

RESULTS

There were 289 729 colonoscopies performed on 249 079 individuals included in the study. There were 16 319 individuals with a colorectal cancer diagnosis 0-36 months after a colonoscopy. Of these, 1286 (7.9%) were PCCRCs. In the multivariate analysis, young age (18-30 years) and former polyp diagnosis had the highest risks [relative risk (RR)=3.3; 95% confidence interval: 2.1-5.2 and RR=3.1; 95% confidence interval: 2.7-3.6]. The impact of other risk factors, such as female sex, comorbidity, right sided colorectal cancer location, and time period, was consistent with the finding in other studies.

CONCLUSION

The prevalence of PCCRC in Sweden seems to be relatively high, indicating that there is room for improvement in colonoscopy quality. The high RR of PCCRC in the youngest age group, even though there were only a few cases, has not been described in other studies.

Crohn's disease: risk factor for colorectal cancer

Background Crohn's disease is an inflammatory disease that can reach any part of the gastrointestinal tract. This disease has been associated with an increased neoplastic risk, including colorectal carcinoma.

Objective The objective of this work is to describe the mechanisms present in two diseases, and that are responsible for the increased risk in Crohn's disease.

Methods A bibliographic research was conducted in PubMed database. In addition to the articles obtained with an inserted query in Pubmed, other references relevant to the topic in question were included.

Results Colorectal cancer risk varies according to the presence of certain factors, and an example of this is Crohn's disease. Chronic inflammation seems to be an important contribution to carcinogenesis, since it creates a microenvironment suitable for the onset and progression of the disease. There are molecular changes that are common to two conditions, thus justifying the fact of Crohn's disease being a risk factor for colorectal carcinoma. The disease control with an appropriate therapy and with surveillance are two ways to control this risk.

Conclusions A proinflammatory state is the cornerstone in the association between Crohn's disease and colorectal carcinoma. The implementation of surveillance strategies allowed a decrease in morbidity and mortality associated with this cancer.

Endoscopy in the Diagnosis and Management of Complications of Inflammatory Bowel Disease

The role of endoscopy in inflammatory bowel disease (IBD) has grown over the last decade in both diagnostic and therapeutic realms. It aids in the initial diagnosis of the disease and also in the assessment of the extent and severity of disease. IBD is associated with development of multiple complications such as strictures, fistulae, and colon cancers. Endoscopy plays a pivotal role in the diagnosis of colon cancer in patients with IBD through incorporation of chromoendoscopy for surveillance. In addition, endoscopic resection with surveillance is recommended in the management of polypoid dysplastic lesions without flat dysplasia. IBD-associated benign strictures with obstructive symptoms amenable to endoscopic intervention can be managed with endoscopic balloon dilation both in the colon and small intestine. In addition, endoscopy plays a major role in assessing the neoterminal ileum after surgery to risk-stratify patients after ileocolonic resection and assessment of a patient with ileoanal pouch anastomosis surgery and management of postsurgical complications. Our article summarizes the current evidence in the role of endoscopy in the diagnosis and management of complications of IBD.

Cancer surveillance in ulcerative colitis and Crohn's disease: new strategies

PURPOSE OF REVIEW

Inflammatory bowel disease (IBD) patients have a higher incidence of colon cancer than the general population. Colon cancer surveillance has traditionally involved taking numerous random biopsies to provide sufficient yield to detect dysplasia. Recently, consensus guidelines have been published which promote the use of chromoendoscopy for IBD colon cancer surveillance. This presents a new set of opportunities and challenges in the evaluation and management of dysplasia in IBD.

RECENT FINDINGS

Dysplasia, previously thought to be 'invisible' to the endoscopist, is now considered to be 'visible' in the majority of cases with the advent of the use of high-definition endoscopy and chromoendoscopy. This changes how we manage dysplastic lesions, providing the patient options for endoscopic resection rather than promoting total proctocolectomy.

SUMMARY

Implemention of chromoendoscopy may require additional training for endoscopists unfamiliar with the technique. However, if this proves to be cost-effective and provides a higher sensitivity in dysplasia detection, then widespread education and implementation will be well worth the efforts. To do so, future studies will need to prove its benefits in preventing or reducing colon cancer morbidity and mortality in this high-risk patient population.

Interval colorectal carcinoma: An unsolved debate

Colorectal carcinoma (CRC), as the third most common new cancer diagnosis, poses a significant health risk to the population. Interval CRCs are those that appear after a negative screening test or examination. The development of interval CRCs has been shown to be multifactorial: location of exam-academic institution versus community hospital, experience of the endoscopist, quality of the procedure, age of the patient, flat versus polypoid neoplasia, genetics, hereditary gastrointestinal neoplasia, and most significantly missed or incompletely excised lesions. The rate of interval CRCs has decreased in the last decade, which has been ascribed to an increased understanding of interval disease and technological advances in the screening of high risk individuals. In this article, we aim to review the literature with regard to the multifactorial nature of interval CRCs and provide the most recent developments regarding this important gastrointestinal entity.

Occult and Manifest Colorectal Carcinoma in Ulcerative Colitis: How Does It Influence Surgical Decision Making?

Background

The incidence of colorectal cancer (CRC) among patients with ulcerative colitis (UC) is increased compared to the general population. The diagnosis of CRC potentially influences surgical decision making in patients with UC.

Methods

This review considers clinical studies, systematic reviews, and guidelines on the surgical therapy of CRC in UC. We searched the bibliographic databases The Cochrane Library and Medline (applying MeSH terms such as ‘Colitis, Ulcerative/surgery’, ‘Colorectal Neoplasms’, and ‘Proctocolectomy, Restorative’) with no restriction on language, date, or country. Search results as well as references of relevant publications were independently screened by both authors of this review.

Results

The surgical gold standard for proven CRC in UC is oncological proctocolectomy, if possible preferably as a restorative procedure with formation of an ileal pouch-anal anastomosis. Mucosectomy and hand-sewn anastomosis is the preferred option for fashioning the anastomosis in these patients, especially in case of dysplasia or cancer in the rectum, although the available data is not conclusive. In highly selected cases of patients with histologically confirmed sporadic CRC without dysplasia in multiple random biopsies and without relevant inflammation, a conventional limited oncological resection is adequate. If UC patients with rectal cancer require radiotherapy, it should be performed in a neoadjuvant setting because of the high risk of radiation-induced pouch failure.

Conclusion

Although restorative proctocolectomy is clearly the gold standard therapy for patients with CRC in UC, surgical decision making has to take into account the various settings and patient factors.

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.

Colorectal cancer in colitis: a relic of the past?

The incidence of dysplasia and colorectal cancer in patients with long-standing colitis seems to be decreasing and controversy surrounds our detection and management strategies. Dysplasia is rarer, flatter, and smaller than in previous decades. Current surveillance guidelines, onerous in terms of colonoscopic workload and an emphasis on random biopsies, have yet to be shown to prevent colon cancers and colon cancer death in these patients. The evidence base for adjunct techniques such as chromoendoscopy is strong but adoption has been slow. We need to better risk-stratify patients with colitis and direct diminishing medical resources accordingly. Modulating dysplasia and cancer risk will involve optimizing medical therapies and focusing our colonoscopic efforts on those who will most likely benefit.