High Risk of Anal and Rectal Cancer in Patients With Anal and/or Perianal Crohn's Disease

Role of innate immunity in tumor microenvironment of HPV-associated anal cancer: The hypothetical beneficial role of γδ T cells

HPV infection plays a crucial role in the formation of the tumor microenvironment, especially in tumors associated with the genital tract, anus, and oropharyngeal region. In this manuscript, we will discuss the main genetic characteristics of HPV and its transmission mechanisms, with a specific focus on the expression of the oncogenes E6 and E7. We will also address the major tumors HPV can generate and their associated epidemiology. In particular, persistent HPV infection induces the release of pro-inflammatory cytokines (such as IL-6 and IL-8), which promote angiogenesis and the recruitment of immunosuppressive immune cells. We will describe on the immune response to the infection, specifically in adaptive immunity, where the virus reduces the expression of MHC class I molecules on infected cells, preventing recognition by cytotoxic T cells. The innate immune response against HPV infection is often ineffective, allowing the virus to persist and contribute to tumor progression. The focus of this work will be on the innate response mediated by γδ T lymphocytes, a subset of CD3 + T cell. Indeed, they recognize HPV-infected cells without the need for antigen presentation by MHC molecules, secrete pro-inflammatory cytokines like IFN-γ and TNF-α, and directly kill HPV-infected cells through cytotoxic mechanisms. In summary, γδ T lymphocytes play an important role in the innate and adaptive immune response against HPV, but the effectiveness of their action can be reduced by the immune evasion mechanisms mediated by the virus. This may occur through the creation of an immunosuppressive environment with the release of immunosuppressive cytokines (such as IL-10 and TGF-β) that inhibit the function of these cells, allowing the virus to persist and contribute to tumor progression. This mechanism has not been well studied in the emerging anal cancer induced by HPV infection, so tracing the state of the art on these aspects could lead to an increase in research in this area and promote the creation of specific immunotherapies that enhance the role of these cells.

Perianal Fistulizing Crohn's Disease-Associated Anorectal and Fistula Cancers: Systematic Review and Expert Consensus

BACKGROUND & AIMS

Perianal fistulizing Crohn's disease (PFCD)-associated anorectal and fistula cancers are rare but often devastating diagnoses. However, given the low incidence and consequent lack of data and clinical trials in the field, there is little to no guidance on screening and management of these cancers. To inform clinical practice, we developed consensus guidelines on PFCD-associated anorectal and fistula cancers by multidisciplinary experts from the international TOpClass consortium.

METHODS

We conducted a systematic review by standard methodology, using the Newcastle-Ottawa Scale quality assessment tool. We subsequently developed consensus statements using a Delphi consensus approach.

RESULTS

Of 561 articles identified, 110 were eligible, and 76 articles were included. The overall quality of evidence was low. The TOpClass consortium reached consensus on 6 structured statements addressing screening, risk assessment, and management of PFCD-associated anorectal and fistula cancers. Patients with long-standing (>10 years) PFCD should be considered at small but increased risk of developing perianal cancer, including squamous cell carcinoma of the anus and anorectal carcinoma. Risk factors for squamous cell carcinoma of the anus, notably human papilloma virus, should be considered. New, refractory, or progressive perianal symptoms should prompt evaluation for fistula cancer. There was no consensus on timing or frequency of screening in patients with asymptomatic perianal fistula. Multiple modalities may be required for diagnosis, including an examination under anesthesia with biopsy. Multidisciplinary team efforts were deemed central to the management of fistula cancers.

CONCLUSIONS

Inflammatory bowel disease clinicians should be aware of the risk of PFCD-associated anorectal and fistula cancers in all patients with PFCD. The TOpClass consortium consensus statements outlined herein offer guidance in managing this challenging scenario.

British Society of Gastroenterology guidelines on colorectal surveillance in inflammatory bowel disease

Patients with inflammatory bowel disease (IBD) remain at increased risk for colorectal cancer and death from colorectal cancer compared with the general population despite improvements in inflammation control with advanced therapies, colonoscopic surveillance and reductions in environmental risk factors. This guideline update from 2010 for colorectal surveillance of patients over 16 years with colonic inflammatory bowel disease was developed by stakeholders representing UK physicians, endoscopists, surgeons, specialist nurses and patients with GRADE (Grading of Recommendations Assessment, Development and Evaluation) methodological support.An a priori protocol was published describing the approach to three levels of statement: GRADE recommendations, good practice statements or expert opinion statements. A systematic review of 7599 publications, with appraisal and GRADE analysis of trials and network meta-analysis, where appropriate, was performed. Risk thresholding guided GRADE judgements.We made 73 statements for the delivery of an IBD colorectal surveillance service, including outcome standards for service and endoscopist audit, and the importance of shared decision-making with patients.Core areas include: risk of colorectal cancer, IBD-related post-colonoscopy colorectal cancer; service organisation and supporting patient concordance; starting and stopping surveillance, who should or should not receive surveillance; risk stratification, including web-based multivariate risk calculation of surveillance intervals; colonoscopic modalities, bowel preparation, biomarkers and artificial intelligence aided detection; chemoprevention; the role of non-conventional dysplasia, serrated lesions and non-targeted biopsies; management of dysplasia, both endoscopic and surgical, and the structure and role of the multidisciplinary team in IBD dysplasia management; training in IBD colonoscopic surveillance, sustainability (green endoscopy), cost-effectiveness and patient experience. Sixteen research priorities are suggested.

Patients' Attitudes to Magnetic Resonance Imaging in Perianal Fistulizing Crohn's Disease: A Global Survey

Background

There is limited patient involvement in radiological research for perianal fistulizing Crohn's disease (pfCD), despite magnetic resonance imaging (MRI)'s critical role in diagnosis and management. Patient and public involvement is essential for aligning research with patient priorities. This study aimed to gather patient perspectives on the use of MRI in pfCD.

Methods

A mixed-methods approach was used, following Guidance for Reporting Involvement of Patients and the Public (GRIPP2) guidelines. An online survey, co-developed with a patient representative, included open and closed questions on MRI experiences, advantages, challenges, and the potential for Artificial Intelligence (AI)-generated reports. This was followed by a virtual session for further exploration of patient views. Thematic analysis was conducted on the data.

Results

Forty-seven patients with Crohn's disease (37 with pfCD) from 6 countries participated, with 28/37 (76%) completing the survey. Key themes included patient expectations for MRI, preferences for scan intervals, and report content. Most (93%) wanted MRI reports to compare with previous scans, highlighting fistula changes and new abscesses. A majority (57%) preferred MRI scans annually when well, and more frequently after surgery (64.3% preferred scans at 3 months). Emotional relief was associated with MRI improvements, though access to services and report clarity remained challenging. Interest in AI-generated reports was expressed if clearly explained and validated by professionals.

Conclusions

This is the first study exploring patient views on MRI use in pfCD, emphasizing the need for patient-centred MRI reporting and clearer communication. Future work should enhance patient access and validate AI-generated MRI reports.

Cancer Characteristics, Prognoses, and Mortality of Colorectal Cancer in Patients With Crohn's Disease-A Danish Nationwide Cohort Study, 2009-2019

BACKGROUND AND AIMS

The aim of this study was to investigate the impact of Crohn's disease (CD) on patient and cancer characteristics and mortality in patients with colorectal cancer (CRC).

METHODS

This was a nationwide cohort study of patients diagnosed with CRC in Denmark from 1 January, 2009 to 31 December, 2019. Cancer characteristics were retrieved from the Danish Colorectal Cancer Group registry and merged with a nationwide cohort for inflammatory bowel disease. The main outcome was all-cause mortality in CRC patients with and without CD, comparing CD patients with CRC with those in the general CRC population (non-CD CRC), evaluated by adjusted Cox regression analysis and propensity score matching.

RESULTS

Of 38 077 CRC patients, 245 (0.6%) had CD. The median age at cancer diagnosis was 69 years (interquartile range [IQR]: 60-76) for CD-CRC and 71 years (IQR: 64-78) for non-CD CRC (p < 0.001). Most cancers were located in the right colon in the CD-CRC group. CD was not associated with increased all-cause mortality in the cohort overall. CD patients with colon and rectal cancers and UICC Stage III tumors had a higher mortality rate in both multivariate {hazard ratio (HR) 1.60 (95% confidence interval [95% CI], 1.13-2.27), p = 0.008} and univariate analyses (HR 1.57 [95% CI, 1.11-2.22], p = 0.011). In the propensity score-matched analysis, CD was not associated with increased mortality for colon cancer (HR 1.06 [0.82-1.36], p = 0.7) or rectal cancer (HR 1.25 [0.79-1.98], p = 0.3).

CONCLUSIONS

This nationwide study identified distinct features of colon and rectal cancers in patients with CD that have implications for the timing of diagnoses, disease course, and mortality specifically in UICC Stage III disease.

Nonfistulizing Perianal Crohn's Disease

Perianal Crohn's disease (CD) includes a wide range of nonfistulizing sequela, including fissures and ulcers, skin tags, anal stricture, and anal cancer. Symptoms related to perianal manifestations of CD are often disabling and have a significant impact on patients' quality of life. They include pain, drainage, bleeding, difficulty with hygiene and may cause secondary difficulties with sexual and defecatory dysfunction. The care of patients with perianal CD requires a thoughtful approach, including detailed history taking, physical examination, and often multidisciplinary care teams to maximize quality of life and ameliorate symptoms.

Quaternized Molecular Brush-Grafted Injectable Microgel with Anti-Inflammatory and Drainage Properties for Efficient Therapy of Anal Fistula

Anal fistula is a common disease with recurrent inflammation and accumulated exudate. Traditional treatments often fail to effectively eliminate inflammation and ensure adequate drainage, leading to prolonged healing time and a high recurrence rate. Herein, a new class of quaternized molecular brush-grafted injectable microgel (denoted as GAA@CNT-g-PVBTMA) is developed through thermal polymerization and mechanical fragmentation to promote the healing process of anal fistula. Benefiting from the fragmented morphology with a porous structure, the microgel can effectively fill the fistula and facilitate the drainage of exudate. Owing to the electrostatic interactions between the positively charged quaternized carbon nanotube molecular brush (CNT-g-PVBTMA) and the negatively charged inflammatory cytokines, GAA@CNT-g-PVBTMA microgel exhibits excellent anti-inflammatory properties with scavenging rates of 92.6% for tumor necrosis factor-α (TNF-α) and 92.5% for interleukin-1β (IL-1β). Rat inflammatory anal fistula model demonstrates that the microgel can effectively reduce inflammation and epithelialization of the fistula, thereby promoting the healing of the anal fistula. By integrating effective filling, adequate drainage, and excellent anti-inflammatory properties, GAA@CNT-g-PVBTMA microgel provides a promising new direction for the treatment of anal fistula.

Tumor necrosis factor receptor-associated factor 5 enhances perianal fistulizing Crohn's disease through epithelial-mesenchymal transition

Objective

Crohn's disease (CD) is a chronic inflammatory condition of the bowel that remarkably impairs a patient's quality of life and often has a poor prognosis. Perianal fistulizing CD (PFCD) is one of the most common parenteral symptoms of CD and a huge challenge for the management of this illness. This study aimed to elucidate the molecular mechanisms underlying PFCD and identify potential biomarkers to advance our understanding and management of this condition.

Material and Methods

Transcriptome sequencing was performed using the control and PFCD groups to investigate the mechanisms of PFCD development. The expression of tumor necrosis factor receptor-associated factor 5 (TRAF5), nuclear factor-kappa B (NF-κB), and interleukin 13 (IL-13) messenger ribonucleic acid (mRNAs) was detected by quantitative polymerase chain reaction (qPCR). Pathological morphology was observed using hematoxylin and eosin staining. The expression of TRAF5, Epithelial Cadherin (E-cadherin), Snail family transcriptional repressor 1 (SNAIL1), and vimentin protein was detected by immunohistochemistry. Following the knockdown of TRAF5 in human tumor-29 (HT-29) cells, the effects on cell proliferation and migration were assessed using the cell counting kit-8 and Transwell assays. The expression levels of crucial markers were analyzed by qPCR, Western blot, and immunohistochemistry.

Results

Transcriptomic sequencing revealed a significant upregulation of TRAF5 in the PFCD group, accompanied by elevated mRNA levels of NF-κB and IL-13 compared with those in the control group. In addition, the PFCD group exhibited increased expression of TRAF5, SNAIL, and vimentin and marked reduction in E-cadherin levels, indicating that PFCD may facilitate epithelial-mesenchymal transition (EMT). Knocking down TRAF5 in HT-29 cells reduced cell proliferation and migration; inhibited NF-κB and IL-13 mRNAs, SNAIL1, and vimentin levels; and promoted E-cadherin levels.

Conclusions

The development of PFCD was associated with EMT, and TRAF5 was a key gene of PFCD. Knocking down TRAF5 alleviated the EMT promotion of PFCD, indicating that TRAF5 drove the development of PFCD through EMT.

Prevalence of HPV in anal cancer: exploring the role of infection and inflammation

Anal cancer incidence is rising globally, driven primarily by human papillomavirus (HPV) infection. HPV, especially high-risk types 16 and 18, is considered a necessary cause of anal squamous cell carcinoma. Certain populations like people living with HIV, men who have sex with men, inflammatory bowel disease patients, smokers, and those with compromised immunity face elevated risk. Chronic inflammation facilitates viral persistence, cell transformation, and immune evasion through pathways involving the PD-1/PD-L1 axis. HIV coinfection further increases risk by impairing immune surveillance and epithelial integrity while promoting HPV oncogene expression. Understanding these inflammatory processes, including roles of CD8 + T cells and PD-1/PD-L1, could guide development of immunotherapies against anal cancer. This review summarizes current knowledge on inflammation's role in anal cancer pathogenesis and the interplay between HPV, HIV, and host immune factors.

Establishment of a surveillance program for anal cancer in Crohn's disease

This letter discusses the incidence of anal cancer among Crohn's disease (CD)-related malignancies. Patients with CD have been demonstrated to be at a higher risk of developing small bowel and colorectal cancers than healthy individuals. Although CD-associated anal cancer is relatively rare, patients with CD accompanied by anal or perianal lesions are at increased risk of anal cancer. Additionally, compared to ulcerative colitis, which is also an inflammatory disease, CD-related anal cancer is often detected at an advanced stage owing to the complexity of CD and is associated with a poor prognosis with frequent local recurrences. Therefore, the detection of early-stage cancer is crucial for improving the prognosis. However, the surveillance methods recommended for CD-related malignancies in the United States and Europe are similar to those for ulcerative colitis. They are not appropriate for detecting CD-related malignancies in the recto-anal region. Therefore, there is an urgent need for surveillance programs aimed at the early detection of malignant anorectal lesions in patients with CD.

Navigating the complexities of perianal Crohn's disease: Diagnostic strategies, treatment approaches, and future perspectives

This article discusses the literature review article by Pacheco et al published in July 2024; the authors provided good reviews of perianal Crohn's disease (CD), and challenges faced by clinicians in the management. CD, characterized by its chronic and relapsing nature, is an idiopathic condition that can involve any segment of the gastrointestinal tract. Perianal disease impacts up to 40% of patients with CD, with perianal fistulas constituting up to 80% of perianal lesions. Perianal CD can be highly incapacitating and profoundly diminish the overall well-being of patients. The management focuses on controlling the perianal sepsis and treating luminal CD. Biologics are crucial to the treatment approach, and results have been encouraging. The surgery focuses on controlling the sepsis, with more definitive treatments being fistula surgery, fecal diversion, and proctectomy as the last resort. This manuscript briefly describes the burden of CD, the challenges posed by perianal CD, and the role of different treatment modalities from colorectal surgeon's perspective.

Persistence, effectiveness and safety of ustekinumab and vedolizumab therapy for complex perianal fistula in Crohn's disease: The HEAL study from GETECCU

BACKGROUND

The efficacy of ustekinumab and vedolizumab for treating complex perianal fistula in Crohn's disease has been barely studied. We aimed to assess treatment persistence, clinical remission, and safety of these drugs in this context.

METHODS

Crohn's disease patients who had received ustekinumab or vedolizumab for the indication of active complex perianal fistula, were included. Clinical remission was defined according to Fistula Drainage Assessment Index (no drainage through the fistula upon gentle pressure) based on physicians' assessment.

RESULTS

Of 155 patients, 136 received ustekinumab, and 35 vedolizumab (16 received both). Median follow-up for ustekinumab was 27 months. Among those on ustekinumab, 54 % achieved remission, and within this group, 27 % relapsed during follow-up. The incidence rate of relapse was 11 % per patient-year. Multivariate analysis found no variables associated with treatment discontinuation or relapse. Median follow-up time for patients receiving vedolizumab was 19 months. Remission was achieved in 46 % of the patients receiving vedolizumab, and among them, 20 % relapsed during follow-up. The incidence rate of relapse was 7 % per patient-year. Adverse events were mild in 6 % on ustekinumab and 8 % on vedolizumab.

CONCLUSION

Ustekinumab and vedolizumab appear effective, achieving remission in around half of complex perianal fistula patients, with favorable safety profiles.

Review article: Measuring disease severity in inflammatory bowel disease - Beyond treat to target

BACKGROUND

Inflammatory bowel disease (IBD) follows a heterogenous disease course and predicting a patient's prognosis is challenging. There is a wide burden of illness in IBD and existing tools measure disease activity at a snapshot in time. Comprehensive assessment of IBD severity should incorporate disease activity, prognosis, and the impacts of disease on a patient. This review investigates the concept of disease severity in adults with IBD to highlight key components contributing to this.

METHODS

To perform this narrative review, a Medline search was conducted for full-text articles available at 1st March 2024 using search terms which encompassed disease activity assessment, disease severity, prognosis, natural history of Crohn's disease (CD) and ulcerative colitis (UC), and the burden of IBD.

RESULTS

Current methods of disease assessment in IBD have evolved from a focus on the burden of symptoms to one that includes inflammatory targets, genetic, serological, and proteomic profiles, and assessments of quality-of-life (QoL), disability, and psychosocial health. Longitudinal studies of IBD suggest that the burden of illness is driven by disease phenotype, clinical markers of complicated disease course (previous intestinal resection, corticosteroid use, perianal disease in CD, recent hospitalisations in UC), gut inflammation, and the impact of IBD on the patient.

CONCLUSIONS

Disease severity in IBD can be difficult to conceptualise due to the multitude of factors that contribute to IBD outcomes. Measurement of IBD severity may better encapsulate the full burden of illness rather than gut inflammation alone at a single timepoint and may be associated with longitudinal outcomes.

Perianal Crohn's disease: Still more questions than answers

In this editorial we comment on the article by Pacheco et al published in a recent issue of the World Journal of Gastroenterology. We focus specifically on the burden of illness associated with perianal fistulizing Crohn's disease (PFCD) and the diagnostic and therapeutic challenges in the management of this condition. Evolving evidence has shifted the diagnostic framework for PFCD from anatomical classification systems, to one that is more nuanced and patient-focused to drive ongoing decision making. This editorial aims to reflect on these aspects to help clinicians face the challenge of PFCD in day-to-day clinical practice.

Management of Perianal Fistulizing Crohn's Disease

Perianal fistulizing Crohn's disease (CD) represents a severe phenotype of CD that is associated with significant morbidity and reduction in quality of life. Perianal fistulizing CD is caused by a complex interplay of genetic predisposition, immune dysregulation, gut dysbiosis, and various unknown physiological and mechanical factors. A multidisciplinary approach is hence required for optimal management . A detailed anatomical description and classification of perianal fistula, including comprehensive clinical, endoscopic, and radiological diagnostic workup, is an important prerequisite to treatment. For simple perianal fistulas, use of antibiotics and immunomodulators, with or without fistulotomy, are appropriate measures. The medical management of complex perianal fistula, on the other hand, requires adequate control of infection before initiation of therapy with immunomodulators. In active complex perianal fistula, anti-tumor necrosis factors remain the most accepted therapy, with concomitant use of antibiotics or immunomodulators enhancing the efficacy. For patients refractory to anti-tumor necrosis factors, treatment with anti-integrins, anti-interleukins, and small molecules is being evaluated. Mesenchymal stem cells, hyperbaric oxygen therapy, and exclusive enteral nutrition have also been investigated as adjunct therapies. Despite the expansion of the medical armamentarium, a large proportion of the patients require surgical interventions. In this review, we provide an up-to-date overview of the pathophysiology, clinical presentation, diagnosis, and medical management of perianal fistulizing CD. A brief overview of the surgical management of perianal fistulizing CD is also provided.

Mucinous Rectal Adenocarcinoma-Challenges in Magnetic Resonance Imaging Interpretation

ABSTRACT

Mucinous rectal cancer (MRC) is defined by the World Health Organization as an adenocarcinoma with greater than 50% mucin content. Classic teaching suggests that it carries a poorer prognosis than conventional rectal adenocarcinoma. This poorer prognosis is thought to be related to mucin dissecting through tissue planes at a higher rate, thus increasing the stage of disease at presentation. Developments in immunotherapy have bridged much of this prognostic gap in recent years. Magnetic resonance imaging is the leading modality in assessing the locoregional spread of rectal cancer. Mucinous rectal cancer carries unique imaging challenges when using this modality. Much of the difficulty lies in the inherent increased T2-weighted signal of mucin on magnetic resonance imaging. This creates difficulty in differentiating mucin from the adjacent background fat, making the detection of both the primary disease process as well as the locoregional spread challenging. Computed tomography scan can act as a valuable companion modality as mucin tends to be more apparent in the background fat. After therapy, diagnostic challenges remain. Mucin is frequently present, and distinguishing cellular from acellular mucin can be difficult. In this article, we will discuss each of these challenges and present examples of such situations and strategies that can be used to overcome them.

Outcomes of Watch-and-Wait Versus Abdominoperineal Resection in Lower Rectal Adenocarcinoma Post Neoadjuvant Therapy: An Iraqi Cohort Study

BACKGROUND

Rectal malignancy ranks among the most prevalent malignancies in humans. Neoadjuvant chemoradiotherapy (nCRT) is advocated as the standard treatment for locally advanced rectal cancer. In patients who achieve complete clinical response (cCR), successive surgical intervention may result in favorable immediate and long-lasting results; however, it may be associated with decreased quality of life. This study aims to evaluate the incidence of local recurrence in rectal adenocarcinoma between patients who underwent a watch-and-wait approach and those who underwent abdominoperineal resection following the achievement of a cCR after nCRT.

METHODS

This is an analytic cohort study that included 68 patients and was conducted in Baghdad Teaching Hospital/Medical City, Baghdad. The data were collected from the 1st of April 2021 to the 1st of October 2023. All patients with stage II and III rectal adenocarcinoma who achieved cCR after receiving nCRT were included in the study.

RESULTS

There was no statistically significant difference between the two study groups regarding non-regrowth disease-free survival (p-value = 0.708). Cox-regression multivariate analysis revealed that baseline T stage and serum carcinoembryonic antigen (CEA) were significantly associated with locoregional failure.

CONCLUSION

The present study reveals that implementing the watch-and-wait strategy had the benefit of avoiding major surgery, stoma, and their complications without coming at the cost of reduced locoregional recurrence.

Perianal disease in inflammatory bowel disease: Broadening treatment and surveillance strategies for anal cancer

The perianal disease affects up to one-third of individuals with Crohn's disease (CD), causing disabling symptoms and significant impairment in quality of life, particularly for those with perianal fistulising CD (PFCD). The collaborative effort between gastroenterologists and surgeons is essential for addressing PFCD to achieve fistula closure and promote luminal healing. Limited fistula healing rates with conventional therapies have prompted the emergence of new biological agents, endoscopic procedures and surgical techniques that show promising results. Among these, mesenchymal stem cells injection is a particularly hopeful therapy. In addition to the burden of fistulas, individuals with perianal CD may face an increased risk of developing anal cancer. This underscores the importance of surveillance programmes and timely interventions to prevent late diagnoses and poor outcomes. Currently, there is no established formal anal screening programme. In this review, we provide an overview of the current state of the art in managing PFCD, including novel medical, endoscopic and surgical approaches. The discussion also focuses on the relevance of establishing an anal cancer screening programme in CD, intending to propose a risk-based surveillance algorithm. The validation of this surveillance programme would be a significant step forward in improving patient care and outcomes.

AGA Clinical Practice Update on Management of Inflammatory Bowel Disease in Patients With Malignancy: Commentary

DESCRIPTION

The purpose of this American Gastroenterological Association (AGA) Institute Clinical Practice Update (CPU) Commentary is to discuss the risks of various malignancies in patients with inflammatory bowel diseases (IBD) and the impact of the available medical therapies on these risks. The CPU will also guide the approach to the patient with IBD who develops a malignancy or the patient with a history of cancer in terms of IBD medication management.

METHODS

This CPU was commissioned and approved by the AGA Institute CPU committee and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership and underwent internal peer review by the CPU committee and external peer review through standard procedures of Clinical Gastroenterology and Hepatology. This communication incorporates important and recently published studies in the field, and it reflects the experiences of the authors who are experts in the diagnosis and management of IBD.

Cancer in Anal Fistulas

Fistula-associated anal cancer in Crohn's disease (CD) can be challenging to diagnose and treat. Patients with longstanding fistulas in the setting of CD who present with a sudden change in their symptoms should undergo biopsy under anesthesia with extensive sampling, followed by staging imaging. Pelvic magnetic resonance imaging (MRI) can be helpful in identifying the extent of the disease locally. Patients often present in the later stages due to the challenges associated with diagnosing these patients. Two subtypes of this disease include squamous cell carcinoma and adenocarcinoma, and treatment depends on diagnosis. Small sample size and lack of uniform data on treatments make it difficult to say which treatment modalities are optimal, but aggressive combined therapy is likely the best approach for survival. This will include chemotherapy and radiation and often radical resection as well. Despite this, survival is poor, although more recent data suggest that outcomes are improving.

Monitoring Patients With Inflammatory Bowel Disease at High Risk of Anal Cancer

Anal cancer is a rare but deadly disease that disproportionately affects patients with inflammatory bowel disease (IBD). Rates of adenocarcinoma and human papillomavirus-related squamous cell carcinoma have been consistently demonstrated to be higher in patients with ulcerative colitis and Crohn's disease. Despite this increased risk, uniform screening, diagnosis, and treatment algorithms are lacking. This review describes the most recent literature surrounding anal cancer in the IBD population as well as the unique challenges inherent in diagnosing and treating this population. We conclude by proposing a new screening motif based off literature review and multidisciplinary clinical experience that aims to increase early detection of anal cancers in the IBD population.

Clinical and magnetic resonance imaging spectrum of complex perianal fistulizing Crohn's disease: A cohort study from northern India

BACKGROUND

Fistulizing perianal Crohn's disease (CD) is a debilitating condition associated with significant morbidity and reduction in the quality of life. Magnetic resonance imaging (MRI) of the pelvis is the preferred imaging modality for the comprehensive assessment of the perianal fistula. There is a paucity of data from India on the MRI spectrum of complex perianal fistula in CD.

METHODS

A single-centre cross-sectional analysis of patients with fistulizing perianal CD, who underwent pelvic MRI between January 2020 and December 2021, was performed. The clinical (age, sex, disease duration, disease location and behavior, disease activity [Perianal Disease Activity Index, PDAI] and treatment received) and radiological (number and location of fistulae, extensions, number and location of internal and external openings, fistula activity, presence or absence of perianal abscess and associated proctitis) characteristics of complex perianal fistula (defined according to the American Gastroenterological Association classification) were recorded.

RESULTS

Of total 175 patients with CD who attended the gastroenterology clinic during the study period, 27 (15.42%) (mean age 42±15.5 years, 62.96% females and median disease duration four years) had complex perianal fistula and were included in the analysis. The mean PDAI was 5.48±2.53. The median Van Assche Index was 17 (interquartile range [IQR] 13-19). A majority (96.29%) of the fistulae were trans-sphincteric and four (14.81%) fistulae extended into the supralevator space. All fistulae were active on MRI. Concomitant perianal abscess and proctitis were seen in 59.26% (n=16) and 62.96% (n=17) of patients, respectively. Combination therapy with biologics and antibiotics/immune-suppressants were the most commonly prescribed medical therapy. Six (22.22%) patients underwent combined medical and surgical (non-cutting seton, fistulectomy, fecal diversion) treatment.

CONCLUSION

The cumulative risk of the development of fistulizing perianal CD in a northern Indian cohort was similar to the western populations. Complex perianal fistulae were predominantly trans-sphincteric and commoner in females. MRI evaluation is pivotal for the delineation of fistula anatomy, assessment of disease extent and activity and the evaluation of concomitant perianal abscess and other complications.

Crohn's Disease-Associated Anorectal Cancer Has a Poor Prognosis With High Local Recurrence: A Subanalysis of the Nationwide Japanese Study

INTRODUCTION

Colorectal cancer (CRC) is one of the major life-threatening complications in patients with Crohn's disease (CD). Previous studies of CD-associated CRC (CD-CRC) have involved only small numbers of patients, and no large series have been reported from Asia. The aim of this study was to clarify the prognosis and clinicopathological features of CD-CRC compared with sporadic CRC.

METHODS

A large nationwide database was used to identify patients with CD-CRC (n = 233) and sporadic CRC (n = 129,783) over a 40-year period, from 1980 to 2020. Five-year overall survival (OS), recurrence-free survival (RFS), and clinicopathological characteristics were investigated. The prognosis of CD-CRC was further evaluated in groups divided by colon cancer and anorectal cancer (RC). Multivariable Cox regression analysis was used to adjust for confounding by unbalanced covariables.

RESULTS

Compared with sporadic cases, patients with CD-CRC were younger; more often had RC, multiple lesions, and mucinous adenocarcinoma; and had lower R0 resection rates. Five-year OS was worse for CD-CRC than for sporadic CRC (53.99% vs 71.17%, P < 0.001). Multivariable Cox regression analysis revealed that CD was associated with significantly poorer survival (hazard ratio 2.36, 95% confidence interval: 1.54-3.62, P < 0.0001). Evaluation by tumor location showed significantly worse 5-year OS and RFS of CD-RC compared with sporadic RC. Recurrence was identified in 39.57% of CD-RC cases and was mostly local.

DISCUSSION

Poor prognosis of CD-CRC is attributable primarily to RC and high local recurrence. Local control is indispensable to improving prognosis.

Anal High-risk Human Papillomavirus Infection, Squamous Intraepithelial Lesions, and Anal Cancer in Patients with Inflammatory Bowel Disease: A Systematic Review and Meta-analysis

BACKGROUND

Ulcerative colitis [UC] and Crohn's disease [CD] can be associated with severe comorbidities, namely opportunistic infections and malignancies. We present the first systematic review and meta-analysis evaluating the burden of anal human papillomavirus disease in patients with UC and CD.

METHODS

PubMed, Web of Science, and Scopus were searched until November 2022. Meta-analyses were performed using random effects models. The protocol was recorded at PROSPERO register with the number CRD42022356728.

RESULTS

Six studies, including 78 711 patients with UC with a total follow-up of 518 969 person-years, described the anal cancer incidence rate. For anal cancer incidence rate in CD, six studies were selected, including 56 845 patients with a total follow-up of 671 899 person-years. The incidence of anal cancer was 10.2 [95% CI 4.3 - 23.7] per 100 000 person-years in UC and 7.7 [3.5 - 17.1] per 100 000 person-years in CD. A subgroup analysis of anal cancer in perianal CD, including 7105 patients, was calculated with incidence of 19.6 [12.2 - 31.6] per 100 000 person-years [three studies included]. Few studies described prevalence of anal cytological abnormalities [four studies including 349 patients] or high-risk human papillomavirus [three studies including 210 patients], with high heterogeneity. Prevalence of cytological abnormalities or high-risk human papillomavirus was not associated with pharmacological immunosuppression in the studies included.

CONCLUSION

The incidence of anal cancer is higher in UC than in CD, with the exception of perianal CD. There are limited and heterogeneous data on anal high-risk human papillomavirus infection and squamous intraepithelial lesions prevalence in this population.

Mucinous and Signet-Ring Cell Colonic Adenocarcinoma in Inflammatory Bowel Disease: A Case-Control Study

A higher frequency of mucinous and signet-ring cell colonic adenocarcinoma has been reported in inflammatory bowel disease (IBD). The primary aim was to investigate the frequency of mucinous and signet-ring cell colorectal adenocarcinoma in patients with IBD (Cases) versus age-matched non-IBD Controls. The secondary aims were to compare the characteristics of these two histotypes of colorectal cancer (CRC) in IBD patients vs. Controls and to search for specific risk factors in IBD. In a case-control study, all IBD patients with CRC diagnosed from 2000 to 2022 were enrolled and matched for age (1:2) with non-IBD Controls with CRC. The study population included 120 CRC patients (40 IBD, 80 Controls). In IBD, CRC included standard adenocarcinoma in 23 (57.5%) patients mucinous/signet-ring cell adenocarcinoma in 17 (42.5%) patients. The proportion of mucinous/signet-ring cell adenocarcinoma was higher in IBD than in Controls (17 [42.5%] vs. 18 [22.5%]; p = 0.03). In rectal CRC, the proportion of mucinous/signet-ring cell adenocarcinoma was higher than standard adenocarcinoma in IBD (8 [47.1%] vs. 4 [17.4%]; p = 0.04) but not in Controls (4 [22.2%] vs. 20 [32.2%]; p = 0.59). In rectal CRC, the proportion of these two histotypes was higher in Cases than in Controls (8/12 [66.6%] vs. 4/24 [16.6%]; p = 0.008), with no risk factors identified in IBD. CRC was more frequently represented by mucinous/signet-ring cell adenocarcinoma in IBD than in age-matched non-IBD Controls. In IBD, these two CRC histotypes were more frequent in the rectum.

Risk of anorectal cancer in patients with Crohn's disease and perianal fistula: a nationwide Danish cohort study

AIM

Patients with Crohn's disease (CD) often suffer from perianal fistulizing disease. Their risk of anorectal cancer remains uncertain. We aimed to examine the long-term risk of anorectal cancer in a population-based cohort of CD patients with anorectal fistula.

METHOD

Our study population covered all individuals (n = 7 987 520) aged 15+ years living in Denmark from 1978 to 2018. We identified all patients with CD and anorectal fistula in the Danish National Patient Register (NPR) and 50 matched noninflammatory bowel disease (IBD) individuals from the general population. Using Cox regression analyses, we examined the risk of anorectal cancer in CD fistula patients versus non-IBD individuals. All patients with CD were identified using codes from the International Classification of Diseases and their data extracted from the NPR. The main outcome measure was cases of anorectal cancer.

RESULTS

A total of 2786 CD patients with anorectal fistula and 139 300 non-IBD individuals were followed for 1 553 917 person-years. During follow-up, anorectal cancer was observed in 19 CD patients (0.68%) and 340 non-IBD individuals (0.24%), corresponding to a 2.9-fold increased hazard ratio (HR) of anorectal cancer in CD fistula patients (95% CI 1.80-4.53), with a particularly high risk of anal cancer (HR 15.13, 95% CI 6.88-33.31) and a mean time from CD fistula diagnosis to anorectal cancer of 6.7 (SD 6.5) years. The risk was slightly higher in women than men and had no apparent relation to treatment with tumour necrosis factor-α inhibitors. Sensitivity analyses using CD nonfistula patients for comparison revealed similar results. Individual data on smoking and infection with human papilloma virus were not available.

CONCLUSION

Patients with CD and anorectal fistula have a three-fold increased risk of anorectal cancer compared with the general population. The number needed to surveil to detect one case of anorectal cancer in this patient population was 2160 patients per year in patients with long-standing fistula (>6 years).

Perianal fistulizing Crohn's disease is associated with a higher prevalence of HPV in the anorectal fistula tract. A comparative study

BACKGROUND & AIMS

Perianal fistulizing Crohn's disease is the main risk factor for anal cancer in patients with inflammatory bowel disease. Whether this occurs due to a higher frequency of human papillomavirus remains unclear. The authors aimed to evaluate the prevalence of HPV and high-risk HPV in patients with perianal Crohn's disease, compared with a control group.

METHODS

The authors conducted a two-center cross-sectional study in which perianal fistulizing Crohn's disease patients were matched for age and sex with patients with anorectal fistula without Crohn's disease. Biopsy specimens were obtained from fistulous tracts during examination under anesthesia for both groups. The samples were sent for HPV detection and genotyping using the INNO-LiPA test.

RESULTS

A total of 108 subjects (54 in each group) were recruited. The perianal fistulizing Crohn's disease group showed a statistically higher frequency of HPV in the fistulous tract than the control group (33.3% vs. 16.7%; p = 0.046). Separate analyses on high-risk types demonstrated that there was a numerically higher frequency of HPV in the perianal fistulizing Crohn's disease group. In multiple logistic regression, patients with perianal fistulizing Crohn's disease were found to have a chance of HPV 3.29 times higher than patients without Crohn's disease (OR = 3.29; 95% CI 1.20‒9.01), regardless of other variables. The types most frequently identified in the perianal fistulizing Crohn's disease group were HPV 11 (12.96%) and HPV 16 (9.26%).

CONCLUSION

Perianal fistulizing Crohn's disease is associated with a higher prevalence of HPV than in patients with anorectal fistula without Crohn's disease.

Malignancy rates in Crohn's disease patients with perianal fistula: A German retrospective cohort study

BACKGROUND

Patients with inflammatory bowel disease are at increased risk of colorectal and extra-intestinal cancer. However, the overall cancer risk in patients with Crohn's disease (CD) with perianal fistulas (PF) (CPF) and those with CD without PF (non-PF CD) is unclear.

OBJECTIVE

To describe the prevalence and incidence of cancer in patients with CPF and non-PF CD, and to estimate incidence rate ratio (IRR) of cancer between CPF and non-PF CD groups.

METHODS

A retrospective cohort study was conducted using the German InGef (Institute for Applied Health Research Berlin) research database. Patients with a CD record and PF from 1 January 2013 to 31 December 2014 were identified and followed up from 1 January 2015 until the first occurrence of cancer, end of health insurance contributing data, death, or end of study period (31 December 2020). Prevalence of any type of cancer including patients with CD diagnosed with cancer in the selection period and incidence of cancer excluding patients with CD diagnosed with cancer in the selection period were calculated.

RESULTS

In total, 10,208 patients with CD were identified. Of 824 patients with CPF (8.1%), 67 had had a malignancy (6-year period crude malignancy prevalence 8.13% [95% confidence interval (CI) 6.36%-10.21%]), which was lower than patients with non-PF CD (19.8% [95% CI 19%-20.6%]). Incidence (per 100,000 person-years) in patients with CPF was 1184 (95% CI 879-1561) and in non-PF CD was 2365 (95% CI 2219-2519). There was no significant difference in the adjusted IRR of cancer for the CPF group compared with the non-PF CD group (0.83 [95% CI 0.62-1.10]; p = 0.219).

CONCLUSION

There was no significant difference in the incidence of any cancer in patients with CPF compared with non-PF CD. However, patients with CPF had a higher numerical risk of cancer than the general German population.

The Optimal Management of Inflammatory Bowel Disease in Patients with Cancer

Patients with inflammatory bowel disease (IBD) have an increased risk of cancer secondary to chronic inflammation and long-term use of immunosuppressive therapy. With the aging IBD population, the prevalence of cancer in IBD patients is increasing. As a result, there is increasing concern about the impact of IBD therapy on cancer risk and survival, as well as the effects of cancer therapies on the disease course of IBD. Managing IBD in patients with current or previous cancer is challenging since clinical guidelines are based mainly on expert consensus. Evidence is rare and mainly available from registries or observational studies. In contrast, excluding patients with previous/or active cancer from clinical trials and short-term follow-up can lead to an underestimation of the cancer or cancer recurrence risk of approved medications. The present narrative review aims to summarize the current evidence and provide practical guidance on the management of IBD patients with cancer.

Perioperative optimization of Crohn's disease

Crohn's disease (CD) is a chronic inflammatory disease mainly affecting the gastrointestinal tract. With the increased availability of modalities in the last two decades, the treatment of CD has advanced remarkably. Although medical treatment is the mainstay of therapy, most patients require surgery during the course of their illness, especially those who experience complications. Nutritional optimization and ERAS implementation are crucial for patients with CD who require surgical intervention to reduce postoperative complications. The increased surgical risk was found to be associated with the use of corticosteroids, but the association of surgical risk with immunomodulators, biologic therapy, such as anti-TNF mediations, anti-integrin medications, and anti-IL 12/23 was low in certainty. Decisions about preoperative medication must be made on an individual case-dependent basis. Preoperative imaging studies can assist in the planning of appropriate surgical strategies and approaches. However, patients must be informed of any alterations to their treatment. In summary, the management of perioperative medications and surgery-related decision-making should be individualized and patient-centered based on a multidisciplinary approach.

Perianal Crohn's disease and the development of colorectal and anal cancer: A systematic review and meta-analysis

BACKGROUND AND AIMS

The aim of this systematic review was to assess the literature on the incidence and risk factors for colorectal cancer and anal cancer in patients with perianal Crohn's disease.

METHOD

A systematic review of the literature was performed using PubMed, Embase and Google Scholar. A meta-analysis was then conducted using a random-effect model.

RESULTS

Five studies were included in the systematic review. Out of all patients, 26.5% had perianal Crohn's Disease. The median follow-up was six years. In total, 127 cases of colorectal cancer were found (0.43% of the included Crohn's disease patients). Perianal involvement was present in 50% of colorectal cancer patients (0.89% of the population). Three of the studies specified the cancer to be rectal or anal, which were present in 68 and 24 cases (0.3% and 0.1% of patients), respectively. In a subgroup analysis of rectal- and anal cancer, perianal involvement was most frequent in anal cancer, accounting for 46% of the cases. In the rectal cancer group, 37% had perianal involvement. The higher incidence of colorectal cancer in patients with perianal Crohn's was confirmed in a meta-analysis.

CONCLUSION

Half of patients with colorectal cancer and anal cancer were found to have perianal Crohn's. In patients with perianal involvement, there was a higher percentage of anal cancer compared with rectal cancer. These results support the theory that patients with perianal Crohn's are at increased risk for developing colorectal- and anal cancer. Studies, collecting more detailed data about patients and their cancers, are necessary to further specify the disease course.

Cancer in Inflammatory Bowel Disease

Inflammatory bowel diseases (IBD), including Crohn disease and ulcerative colitis, are chronic inflammatory conditions of the gastrointestinal tract. Individuals with IBD are at increased risk for several malignancies originating in the intestine, such as colorectal cancer, small bowel adenocarcinoma, intestinal lymphoma, and anal cancer. There are also several extraintestinal malignancies associated with IBD and IBD therapies, including cholangiocarcinoma, skin cancer, hematologic malignancies, genitourinary cancer, cervical cancer, and prostate cancer. The authors summarize the risk of cancer in patients with IBD, diagnosis and management of colorectal neoplasia in IBD, and management of patients with IBD and active or recent cancer.

Risk of Anorectal Cancer Associated with Benign Anal Inflammatory Diseases: A Retrospective Matched Cohort Study

Purpose: The purpose of our study was to evaluate the relationship between benign anal inflammatory diseases and anorectal cancer and assess its risk factors. Methods: A retrospective matched cohort study was conducted that included data from 2002 to 2013. The National Health Insurance Service National Sample Cohort data from 2002 to 2013 was used for the study. Of a total study population of 143,884 individuals, 28,110 individuals with anal fissures were assigned to the case group, while 115,774 individuals without anal fissures were assigned to the control group based on the 1:4 propensity score matching age, sex, and year (case: diagnosed year, control: health service received year). Results: The risk of anorectal cancer was higher in the case group (hazard ratio [HR]: 1.95, 95% confidence interval [CI]: 1.51–2.53) compared to the control group. After grouping anorectal cancers into anal cancer and rectal cancer, the risk remained higher in the case group (anal cancer HR: 2.79, 95% CI: 1.48–5.27; rectal cancer HR: 1.82, 95% CI; 1.37–2.42). The case group was further categorized into patients with fissures and patients with fistulas; patients with fissures showed a higher risk of developing anorectal cancer than patients with fistulas (HR: 2.05, 95% CI: 1.53–2.73 vs. HR: 1.73, 95% CI: 1.13–2.66). Study participants in their 30s and 40s had a 4.19- and 7.39-times higher risk of anorectal cancer compared to those in the higher age groups (0.64–1.84), while patients who did not have inflammatory bowel disease (IBD) had a higher risk of developing anorectal cancer (HR: 2.09, 95% CI: 1.56–2.80). Conclusions and Relevance: Patients with anal fistulas or fissures have an increased risk of being diagnosed with anorectal cancer, especially at a young age and even without IBD.

The Role of Inflammation in Anal Cancer

The aim of this article was to present a summary of the current resources available in the literature regarding the role of inflammation in anal cancer development. Anal cancer is relatively uncommon, accounting for about 2.7% of all reported gastrointestinal cancers in the United States. However, the importance of understanding the pathogenesis and risk factors for anal cancer has been recognized over the last several decades due to a noticed increase in incidence worldwide. Infections, autoimmune diseases, and inflammatory diseases of unknown etiology cause chronic inflammation that promotes tumorigenesis. The association between chronic inflammation and cancer development is widely accepted. It is based on different pathophysiological mechanisms that lead to cellular transformation and changes in immunological response, allowing tumor cells to avoid apoptosis and immune surveillance. However, there are still many molecular and cellular mechanisms that remain largely unexplored. Further studies on this topic could be of tremendous significance in elucidating anal cancer pathogenesis and developing immunotherapeutic approaches for its treatment.

Perianal Crohn's Disease Is Associated With Poor Disease Outcome: A Nationwide Study From the epiIIRN Cohort

BACKGROUND & AIMS

Limited population-based data have explored perianal involvement in Crohn's disease (CD) and compared the disease course between severe and non-severe perianal CD (PCD). We aimed to explore the disease course of these phenotypes in a population-based study of CD.

METHODS

Cases were identified from the epi-IIRN cohort and included 2 Israeli health maintenance organizations covering 78% of the population. We validated specific algorithms to identify fistulizing PCD and to differentiate severe from non-severe disease by medication utilization, International Classification of Disease, 9th Revision codes, and perianal procedures.

RESULTS

A total of 12,904 CD patients were included in an inception cohort from 2005 (2186 pediatric-onset, 17%) providing 86,119 person-years of follow-up. Fistulizing PCD was diagnosed in 1530 patients (12%) (574 with severe PCD, 4%). The prevalence of PCD was 7.9%, 9.4%, 10.3%, and 11.6% at 1, 3, 5, and 10 years from CD diagnosis, respectively. At 5 years, PCD patients were more likely to be hospitalized (36% in non-PCD vs 64% in PCD; P < .001), undergo inflammatory bowel disease-related surgeries (9% vs 38%, respectively; P < .001), and develop anorectal cancer (1.2/10,000 person-years for non-PCD vs 4.2/10,000 for PCD; P = .01). Severe PCD was associated with poorer outcomes compared with non-severe PCD, as shown for hospitalizations (61% in non-severe PCD vs 73% in severe; P = .004) and surgeries (35% vs 43%; P = .001).

CONCLUSIONS

Despite higher utilization of immunomodulators and biologics, PCD is associated with poor disease outcomes, especially in severe PCD.

Anal neoplasia and perianal Crohn's disease: myth or reality?

The association between inflammatory bowel disease (IBD) and anal canal squamous cell carcinoma (SCC) has a low prevalence and is mainly supported by articles that include a series of cases. We describe the clinical, endoscopic and histological findings of a patient with Crohn's disease (CD) who developed SCC while undergoing biological therapy with active disease.

Incident Colorectal Cancer in Inflammatory Bowel Disease

Colorectal cancer (CRC) risk is increased in Inflammatory Bowel Disease (IBD) and surveillance needs to be tailored according to individual risk. The open issues include the role of the characteristics of IBD and CRC in determining the long-term outcome. These issues were assessed in our multicenter study, including a cohort of 56 IBD patients with incident CRC. The clinical and histopathological features of IBD patients and of CRC were recorded. Incident CRC in IBD occurred at a young age (≤40 years) in 25% of patients (median age 55.5 (22-76)). Mucinous signet-ring carcinoma was detected in 6 out of the 56 (10.7%) patients, including 4 with Ulcerative Colitis (UC) and 2 with Crohn's disease (CD). CRC was more frequently diagnosed by colonoscopy in UC (85.4% vs. 50%; p = 0.01) and by imaging in Crohn's Disease CD (5.8% vs. 31.8%; p = 0.02). At onset, CRC-related symptoms occurred in 29 (51.9%) IBD patients. The time interval from the diagnosis of IBD to CRC was shorter in UC and CD patients with >40 years (p = 0.002; p = 0.01). CRC-related death occurred in 10 (29.4%) UC and in 6 (27.2%) CD patients (p = 0.89), with a short time interval from CRC to death (UC vs. CD: 6.5 (1-68) vs. 14.5 (8-40); p = 0.85; IBD: 12 months (1-68)). CRC occurring at a young age, a short time interval from the diagnosis of IBD to CRC-related death in the elderly, CRC-symptoms often mimicking IBD relapse and the observed high mortality rate may support the need of closer surveillance intervals in subgroups of patients.

A Multi-Disciplinary Approach to Perianal Fistulizing Crohn's Disease

Perianal fistulizing Crohn's disease represents a severe phenotype associated with significant morbidity. Patients with perianal fistulizing disease are more likely to have a severe disease course and have significant reductions in quality of life. Moreover, these patients are at risk for the development of distal rectal and anal cancers. Given the complexity and severity of this patient group, the management of perianal Crohn's disease must be undertaken by a multidisciplinary team. The gastroenterologist and colorectal surgeon play a critical role in the diagnosis and management of perianal fistulizing disease. An examination under anesthesia provides critical information and is an essential part of the work-up of complex perianal fistulas. The radiologist also plays a central role in characterizing anatomy and assessing response to treatment. Several imaging modalities are available for these patients with magnetic resonance imaging as the imaging modality of choice. Perianal disease developing after ileal pouch-anal anastomosis represents a particularly challenging form of fistulizing disease and requires a multidisciplinary clinical and radiologic approach to differentiate surgical complications from recurrent Crohn's disease.

Perianal Fistula-Associated Carcinoma in Crohn's Disease: A Multicentre Retrospective Case Control Study

BACKGROUND AND AIMS

Carcinoma associated with perianal fistula in Crohn's disease is a pending threat for patients. This study aimed to improve understanding and facilitate development of diagnostic and therapeutic strategies.

METHODS

A retrospective case-control study was conducted at four German hospitals. The analysis included 40 patients with proven malignancy associated with perianal Crohn's fistulas and 40 randomly selected controls with fistulizing perianal Crohn's disease. Differences between groups were analysed and multivariate calculations were performed to describe risk factors for oncological outcomes.

RESULTS

Histology revealed adenocarcinoma in 33/40 patients and squamous cell carcinoma in 7/40 patients. Compared to fistula patients without carcinoma, patients with malignancies associated with fistula had a diagnosis of Crohn's disease at younger age. Crohn's disease lasted longer in patients with malignancy [25.8 ± 9.0 vs 19.6 ± 10.4; p = 0.006]. Fistula-related findings differed significantly between the two groups. Signs of complicated and severe fistulation including complex anatomy and chronic activity occurred significantly more often in patients with malignancy associated with fistula. Significant multivariate hazard ratios for overall mortality and progression-free survival were shown for histological type of cancer, metastatic disease and R1 resection. Overall survival was 45.1 ± 28.6 months and the 5-year survival rate was 65%.

CONCLUSIONS

In patients with adenocarcinoma or squamous cell carcinoma associated with perianal fistula in Crohn's disease, fistula characteristics determine the risk of malignancy. Early diagnosis influences outcomes, while treatment of chronic fistula activity may be key to preventing malignancy. Expert multimodal therapy is paramount for successful treatment of perianal fistula-associated malignancies.

Diagnosis and classification of ileal pouch disorders: consensus guidelines from the International Ileal Pouch Consortium

Restorative proctocolectomy with ileal pouch-anal anastomosis is an option for most patients with ulcerative colitis or familial adenomatous polyposis who require colectomy. Although the construction of an ileal pouch substantially improves patients' health-related quality of life, the surgery is, directly or indirectly, associated with various structural, inflammatory, and functional adverse sequelae. Furthermore, the surgical procedure does not completely abolish the risk for neoplasia. Patients with ileal pouches often present with extraintestinal, systemic inflammatory conditions. The International Ileal Pouch Consortium was established to create this consensus document on the diagnosis and classification of ileal pouch disorders using available evidence and the panellists' expertise. In a given individual, the condition of the pouch can change over time. Therefore, close monitoring of the activity and progression of the disease is essential to make accurate modifications in the diagnosis and classification in a timely manner.

A Novel Model for Papillomavirus-Mediated Anal Disease and Cancer Using the Mouse Papillomavirus

Up to 95% of all anal cancers are associated with infection by human papillomavirus (HPV); however, no established preclinical model exists for high-grade anal disease and cancer mediated by a natural papillomavirus infection. To establish an infection-mediated model, we infected both immunocompromised NSG and immunocompetent FVB/NJ mice with the recently discovered murine papillomavirus MmuPV1, with and without the additional cofactors of UV B radiation (UVB) and/or the chemical carcinogen 7,12-dimethylbenz(a)anthracene (DMBA). Infections were tracked via lavages and swabs for MmuPV1 DNA, and pathology was assessed at the endpoint. Tissues were analyzed for biomarkers of viral infection and papillomavirus-mediated disease, and the localization of viral infection was investigated using biomarkers to characterize the anal microanatomical zones.