Reduced Risk of Inflammatory Bowel Disease-associated Colorectal Neoplasia with Use of Thiopurines: a Systematic Review and Meta-analysis

Innovations in colorectal cancer treatment: trifluridine and tipiracil with bevacizumab for improved outcomes - a review

Colorectal cancer ranks second in cancer-related deaths throughout the world. At the time of diagnosis, at least 20% of the patients with CRC had already developed metastases. Treating and effectively managing metastatic colorectal cancer remains an unsolved task for the health sector. Research and clinical trials have been done to find the best possible solution for patients diagnosed with metastatic colorectal cancer. The approval of the combination therapy of trifluridine and tipiracil with bevacizumab for previously treated metastatic colorectal cancer (CRC) by the Food and Drug Administration (FDA) is a remarkable breakthrough in CRC treatment. Our goal through this article is to give detailed knowledge about the pathogenesis of CRC, its prevalence, and its clinical features. Here, we have also discussed the past medical treatments that have been used for treating mCRC, including the anti-EGFR therapy, aflibercept, ramucirumab, and regorafenib. However, the focus of this document is to assess the combination of LONSURF (trifluridine/tipiracil) and bevacizumab by reviewing the clinical trials and relevant research.

Additional Yield of Random Biopsy in Patients With Inflammatory Bowel Disease: A Systematic Review and Meta-Analysis

BACKGROUND

There are limited clinical data regarding the additional yields of random biopsies (RBs) during colorectal cancer surveillance in patients with inflammatory bowel disease. To assess the additional yield of RB, a systematic review and meta-analysis was conducted.

METHODS

PubMed, Embase, Web of Science, and the Cochrane Library were searched for studies investigating the preferred colonoscopy surveillance approach for inflammatory bowel disease patients. The additional yield, detection rate, procedure time, and withdrawal time were pooled.

RESULTS

Thirty-seven studies (48 arms) were included in the meta-analysis with 9051 patients. The additional yields of RB were 10.34% in per-patient analysis and 16.20% in per-lesion analysis. The detection rates were 1.31% and 2.82% in per-patient and per-lesion analysis, respectively. Subgroup analysis showed a decline in additional yields from 14.43% to 0.42% in the per-patient analysis and from 19.20% to 5.32% in the per-lesion analysis for studies initiated before and after 2011. In per-patient analysis, the additional yields were 4.83%, 10.29%, and 56.05% for primary sclerosing cholangitis (PSC) proportions of 0% to 10%, 10% to 30%, and 100%, respectively. The corresponding detection rates were 0.56%, 1.40%, and 19.45%. In the per-lesion analysis, additional yields were 11.23%, 21.06%, and 45.22% for PSC proportions of 0% to 10%, 10% to 30%, and 100%, respectively. The corresponding detection rates were 2.09%, 3.58%, and 16.24%.

CONCLUSIONS

The additional yields of RB were 10.34% and 16.20% for per-patient and per-lesion analyses, respectively. Considering the decreased additional yields in studies initiated after 2011, and the influence of PSC, endoscopy centers lacking full high-definition equipment should consider incorporating RB in the standard colonoscopy surveillance for inflammatory bowel disease patients, especially in those with PSC.

Colorectal Neoplasia in the Setting of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is associated with an increased risk of colorectal cancer (colorectal adenocarcinoma [CRC]) compared with the general population. IBD-related CRC is related to poorer outcomes than non-IBD-related CRC, and it accounts for 10% to 15% of death in patients with IBD. As such, screening guidelines have been made specific to this population recommending shorter intervals of endoscopic screening to detect dysplasia and CRC relative to the general population. Advances in endoscopic technology allow for improved visualization of dysplasia, which has led to widespread adoption of dye-spray chromoendoscopy with targeted biopsy.

Chemoprophylaxis of precancerous lesions in patients who are at a high risk of developing colorectal cancer (Review)

The diagnostics of colorectal cancer (CRC) and precancerous lesions in the colon is one of the most urgent matters to be considered for the modern protocols of complex examination, recommended for use from the age of 45 years, and including both instrumental and laboratory methods of research: Colonoscopy, CT colonography, flexible sigmoidoscopy, fecal occult blood test, fecal immunohistochemistry test and stool DNA test Nevertheless, the removal of those precancerous lesions does not solve the issue, and, apart from the regular endoscopic monitoring of patients who are at a high risk of developing CRC, the pharmacological treatment of certain key pathogenic mechanisms leading to the development of CRC is required. The present review to discusses the function of β-catenin in the transformation of precancerous colorectal lesions into CRC, when collaborating with PI3K/AKT/mTOR signaling pathway and other mechanisms. The existing methods for the early diagnostics and prevention of discovered anomalies are described and categorized. The analysis of the approaches to chemoprophylaxis of CRC, depending on the results of endoscopic, morphological and molecular-genetic tests, is presented.

Overcoming cancer risk in inflammatory bowel disease: new insights into preventive strategies and pathogenesis mechanisms including interactions of immune cells, cancer signaling pathways, and gut microbiota

Inflammatory bowel disease (IBD), characterized primarily by gastrointestinal inflammation, predominantly manifests as Crohn's disease (CD) and ulcerative colitis (UC). It is acknowledged that Inflammation plays a significant role in cancer development and patients with IBD have an increased risk of various cancers. The progression from inflammation to carcinogenesis in IBD is a result of the interplay between immune cells, gut microbiota, and carcinogenic signaling pathways in epithelial cells. Long-term chronic inflammation can lead to the accumulation of mutations in epithelial cells and the abnormal activation of carcinogenic signaling pathways. Furthermore, Immune cells play a pivotal role in both the acute and chronic phases of IBD, contributing to the transformation from inflammation to tumorigenesis. And patients with IBD frequently exhibit dysbiosis of the intestinal microbiome. Disruption of the gut microbiota and subsequent immune dysregulation are central to the pathogenesis of both IBD and colitis associated colorectal cancer (CAC). The proactive management of inflammation combined with regular endoscopic and tumor screenings represents the most direct and effective strategy to prevent the IBD-associated cancer.

Stromal inflammation, fibrosis and cancer: An old intuition with promising potential

It is now well established that the biology of cancer is influenced by not only malignant cells but also other components of the tumour microenvironment. Chronic inflammation and fibrosis have long been postulated to be involved in carcinogenesis. Chronic inflammation can promote tumorigenesis via growth factor/cytokine-mediated cellular proliferation, apoptotic resistance, immunosuppression; and free-radical-induced oxidative deoxyribonucleic acid damage. Fibrosis could cause a perturbation in the dynamics of the tumour microenvironment, potentially damaging the genome surveillance machinery of normal epithelial cells. In this review, we will provide an in-depth discussion of various diseases characterised by inflammation and fibrosis that have been associated with an increased risk of malignancy. In particular, we will present a comprehensive overview of the impact of alterations in stromal composition on tumorigenesis, induced as a consequence of inflammation and/or fibrosis. Strategies including the application of various therapeutic agents with stromal manipulation potential and targeted cancer screening for certain inflammatory diseases which can reduce the risk of cancer will also be discussed.

Barriers in inflammatory bowel disease care in Central and Eastern Europe: a region-specific analysis

Inflammatory bowel diseases (IBD), including Crohn's disease and ulcerative colitis, are chronic immune-mediated diseases with a high incidence and prevalence in Europe. Since these are diseases with associated disability, they require complex management and the availability of high-quality healthcare resources. We focused on the analysis of IBD care in selected countries of Central and Eastern Europe (Croatia, the Czech Republic, Hungary, Moldova, Poland, Romania and Slovakia) targeting the availability and reimbursement of diagnostic and therapeutic modalities, the role of IBD centers and also education and research in IBD. As part of the analysis, we created a questionnaire of 73 statements organized in three topics: (1) diagnostics, follow-up and screening, (2) medications and (3) IBD centers. The questionnaire was filled out by co-authoring IBD experts from individual countries, and then the answers and comments on the questionnaire were analyzed. We identified that despite the financial burden, which still partially persists in the region, the availability of some of the cost-saving tools (calprotectin test, therapeutic drug monitoring) differs among countries, mainly due to variable reimbursement from country to country. In most participating countries, there also remains a lack of dedicated dietary and psychological counseling, which is often replaced by recommendations offered by gastroenterologists. However, there is adequate availability of most of the currently recommended diagnostic methods and therapies in each participating country, as well as the implementation of established IBD centers in the region.

Inflammation-Driven Colorectal Cancer Associated with Colitis: From Pathogenesis to Changing Therapy

Patients affected by inflammatory bowel disease (IBD) have a two-fold higher risk of developing colorectal cancer (CRC) than the general population. IBD-related CRC follows a different genetic and molecular pathogenic pathway than sporadic CRC and can be considered a complication of chronic intestinal inflammation. Since inflammation is recognised as an independent risk factor for neoplastic progression, clinicians strive to modulate and control disease, often using potent therapy agents to achieve mucosal healing and decrease the risk of colorectal cancer in IBD patients. Improved therapeutic control of inflammation, combined with endoscopic advances and early detection of pre-cancerous lesions through surveillance programs, explains the lower incidence rate of IBD-related CRC. In addition, current research is increasingly focused on translating emerging and advanced knowledge in microbiome and metagenomics into personalised, early, and non-invasive CRC screening tools that guide organ-sparing therapy in IBD patients. This review aims to summarise the existing literature on IBD-associated CRC, focusing on new insights into the alteration of the intestinal barrier and the interactions with the gut microbiome as the initial promoter. In addition, the role of OMIC techniques for precision medicine and the impact of the available IBD therapeutic armamentarium on the evolution to CRC will be discussed.

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.

Advances in research on the effectiveness and mechanism of Traditional Chinese Medicine formulas for colitis-associated colorectal cancer

Inflammatory bowel disease (IBD) can progress into colitis-associated colorectal cancer (CAC) through the inflammation-cancer sequence. Although the mechanism of carcinogenesis in IBD has not been fully elucidated, the existing research indicates that CAC may represent a fundamentally different pathogenesis pattern of colorectal cancer. At present, there is no proven safe and effective medication to prevent IBD cancer. In recent years, Chinese medicine extracts and Chinese medicine monomers have been the subject of numerous articles about the prevention and treatment of CAC, but their clinical application is still relatively limited. Traditional Chinese Medicine (TCM) formulas are widely applied in clinical practice. TCM formulas have demonstrated great potential in the prevention and treatment of CAC in recent years, although there is still a lack of review. Our work aimed to summarize the effects and potential mechanisms of TCM formulas for the prevention and treatment of CAC, point out the issues and limitations of the current research, and provide recommendations for the advancement of CAC research in the future. We discovered that TCM formulas regulated many malignant biological processes, such as inflammation-mediated oxidative stress, apoptosis, tumor microenvironment, and intestinal microecology imbalance in CAC, through a review of the articles published in databases such as PubMed, SCOPUS, Web of Science, Embase, and CNKI. Several major signal transduction pathways, including NF-κB, STAT3, Wnt/β-catenin, HIF-1α, and Nrf2, were engaged. TCM formula may be a promising treatment candidate to control the colitis-cancer transformation, however further high-quality research is required.

Risk of Cancer in Patients with Inflammatory Bowel Diseases and Keys for Patient Management

Chronic inflammation in patients with Inflammatory Bowel Disease (IBD) leads to an increased risk of colorectal cancer, small bowel cancer, intestinal lymphoma and cholangiocarcinoma. However, treatments for IBD have also been associated with an increased risk of neoplasms. Patients receiving Thiopurines (TPs) have an increased risk of hematologic malignancies, non-melanoma skin cancer, urinary tract neoplasms and cervical cancer. Anti-TNFs have been associated with a higher risk of neoplasms, mainly lymphomas and melanomas; however, the data are controversial, and some recent studies do not confirm the association. Nevertheless, other biologic agents, such as ustekinumab and vedolizumab, have not shown an increased risk of any neoplasm to date. The risk of malignancies with tofacitinib exists, but its magnitude and relationship with previous treatment with TPs is not defined, so more studies from daily clinical practice are needed. Although biologic therapy seems to be safe for patients with current cancer or a prior history of cancer, as has been demonstrated in other chronic inflammatory conditions, prospective studies in this specific population are needed. Until that time, it is crucial to manage such conditions via the combined clinical expertise of the gastroenterologist and oncologist.

The Appendix Orchestrates T-Cell Mediated Immunosurveillance in Colitis-Associated Cancer

BACKGROUND & AIMS

Although appendectomy may reduce colorectal inflammation in patients with ulcerative colitis (UC), this surgical procedure has been suggested to be associated with an increased risk of colitis-associated cancer (CAC). Our aim was to explore the mechanism underlying the appendectomy-associated increased risk of CAC.

METHODS

Five-week-old male BALB/c mice underwent appendectomy, appendicitis induction, or sham laparotomy. They were then exposed to azoxymethane/dextran sodium sulfate (AOM/DSS) to induce CAC. Mice were killed 12 weeks later, and colons were taken for pathological analysis and immunohistochemistry (CD3 and CD8 staining). Human colonic tumors from 21 patients with UC who underwent surgical resection for CAC were immunophenotyped and stratified according to appendectomy status.

RESULTS

Whereas appendectomy significantly reduced colitis severity and increased CAC number, appendicitis induction without appendectomy led to opposite results. Intratumor CD3+ and CD8+ T-cell densities were lower after appendectomy and higher after appendicitis induction compared with the sham laparotomy group. Blocking lymphocyte trafficking to the colon with the anti-α4β7 integrin antibody or a sphingosine-1-phosphate receptor agonist suppressed the inducing effect of the appendectomy on tumors' number and on CD3+/CD8+ intratumoral density. CD8+ or CD3+ T cells isolated from inflammatory neo-appendix and intravenously injected into AOM/DSS-treated recipient mice increased CD3+/CD8+ T-cell tumor infiltration and decreased tumor number. In UC patients with a history of appendectomy, intratumor CD3+ and CD8+ T-cell densities were decreased compared with UC patients without history of appendectomy.

CONCLUSIONS

In UC, appendectomy could suppress a major site of T-cell priming, resulting in a less efficient CAC immunosurveillance.

Global research trends on inflammatory bowel diseases and colorectal cancer: A bibliometric and visualized study from 2012 to 2021

Inflammatory bowel disease (IBD) is a chronic non-specific inflammatory disease of intestinal tract and a common digestive system disease. Current studies have shown that IBD significantly increases the incidence of colorectal cancer (CRC), and is positively correlated with the degree and extent of inflammation of IBD. The relationship between IBD and CRC has attracted extensive attention. However, the relationship between IBD and CRC has not been systematically studied by bibliometrics and visual analysis. This study conducted bibliometric analysis based on 3528 publications from the Core Collection of Web of Science to determine the research status, research hotspots and frontiers of this field. The results show that the number of publications has increased significantly over the past 10 years. The cooperative network analysis shows that the United States, Mayo Clin and Bo Shen are the country, institution and author with the most publications respectively. Belgium, Icahn Sch Med Mt Sinai and Erik Mooiweer are the most collaborative country, institution and author respectively. Analysis of keywords and references showed that inflammation, intestinal flora, and obesity were hot topics in this field. Analysis of keyword outbreaks shows that the gut microbiome and metabolism will be an emerging new research area and a potential hot spot for future research. This study is the first to visually examine the association between IBD and CRC using bibliometrics and visual analysis, and to predict potential future research trends.

Chemoprevention of Colitis-Associated Dysplasia or Cancer in Inflammatory Bowel Disease

The association between inflammatory bowel disease and colorectal cancer is well known. Although the overall incidence of inflammatory bowel disease has declined recently, patients with this disease still have a 1.7-fold increased risk of colorectal cancer. The risk factors for developing colorectal cancer include extensive colitis, young age at diagnosis, disease duration, primary sclerosing cholangitis, chronic colonic mucosal inflammation, dysplasia lesion, and post-inflammatory polyps. In patients with inflammatory bowel disease, control of chronic inflammation and surveillance colonoscopies are important for the prevention of colorectal cancer. The 2017 guidelines from the European Crohn's and Colitis Organisation suggest that colonoscopies to screen for colorectal cancer should be performed when inflammatory bowel disease symptoms have lasted for 8 years. Current evidence supports the use of chemoprevention therapy with mesalamine to reduce the risk of colorectal cancer in patients with ulcerative colitis. Other compounds, including thiopurine, folic acid, statin, and tumor necrosis factor-α inhibitor, are controversial. Large surveillance cohort studies with longer follow-up duration are needed to evaluate the impact of drugs on colorectal cancer risks.

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

Simple Summary

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

Abstract

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

Impact of Anti-tumour Necrosis Factor Agents on the Risk of Colorectal Cancer in Patients with Ulcerative Colitis: Nationwide French Cohort Study

BACKGROUND AND AIMS

Patients with ulcerative colitis [UC] are at increased risk of colorectal cancer. Anti-tumour necrosis factor agents [anti-TNF] aim to reduce chronic colonic inflammation and may lower the risk of colorectal cancer [CRC], but the impact of anti-TNF exposure has not yet been assessed in population-based cohort studies. The aim of this nationwide study was to assess the risk of CRC in patients with UC exposed to anti-TNF.

METHODS

Based on the French health insurance database, patients aged 18 years or older with a diagnosis of UC, previously exposed to or initiating immunosuppressive treatment, were followed from January 1, 2009, until December 31, 2018. The risk of CRC associated with anti-TNF exposure was assessed using marginal structural Cox proportional hazard models adjusting for baseline and time-varying comorbidities including primary sclerosing cholangitis, UC disease activity, colonoscopic surveillance, and other medications.

RESULTS

Among 32 403 patients with UC, 15 542 [48.0%] were exposed to anti-TNF. During a median follow-up of 6.1 years [198 249 person-years], 246 incident CRC occurred (incidence rate per 1000 person-years, 1.24; 95% confidence intrval [CI], 1.10-1.41). Whereas the risk of CRC associated with anti-TNF exposure was not decreased in the overall group of patients with UC (hazard ratio [HR], 0.85; 95% CI, 0.58-1.26), anti-TNF exposure was associated with a decreased risk of CRC in patients with long-standing colitis [disease duration ≥10 years] [HR, 0.41; 95% CI, 0.20-0.86].

CONCLUSIONS

In a nationwide cohort of patients with UC, anti-TNF exposure was associated with a decreased risk of CRC in patients with long-standing colitis.

Oral Conventional Synthetic Disease-Modifying Antirheumatic Drugs with Antineoplastic Potential: a Review

There is an increasing trend of malignancy worldwide. Disease-modifying antirheumatic drugs (DMARDs) are the cornerstones for the treatment of immune-mediated inflammatory diseases (IMIDs), but risk of malignancy is a major concern for patients receiving DMARDs. In addition, many IMIDs already carry higher background risks of neoplasms. Recently, the black box warning of malignancies has been added for Janus kinase inhibitors. Also, the use of biologic DMARDs in patients with established malignancies is usually discouraged owing to exclusion of such patients in pivotal studies and, hence, lack of evidence. In contrast, some conventional synthetic DMARDs (csDMARDs) have been reported to show antineoplastic properties and can be beneficial for patients with cancer. Among the csDMARDs, chloroquine and hydroxychloroquine have been the most extensively studied, and methotrexate is an established chemotherapeutic agent. Even cyclosporine A, a well-known drug associated with cancer risk, can potentiate the effect of some chemotherapeutic agents. We review the possible mechanisms behind and clinical evidence of the antineoplastic activities of csDMARDs, including chloroquine and hydroxychloroquine, cyclosporine, leflunomide, mycophenolate mofetil, mycophenolic acid, methotrexate, sulfasalazine, and thiopurines. This knowledge may guide physicians in the choice of csDMARDs for patients with concurrent IMIDs and malignancies.

Azathioprine with Allopurinol Is a Promising First-Line Therapy for Inflammatory Bowel Diseases

BACKGROUND

Beneficial response to first-line immunosuppressive azathioprine in patients with inflammatory bowel disease (IBD) is low due to high rates of adverse events. Co-administrating allopurinol has been shown to improve tolerability. However, data on this co-therapy as first-line treatment are scarce.

AIM

Retrospective comparison of long-term effectiveness and safety of first-line low-dose azathioprine-allopurinol co-therapy (LDAA) with first-line azathioprine monotherapy (AZAm) in patients with IBD without metabolite monitoring.

METHODS

Clinical benefit was defined as ongoing therapy without initiation of steroids, biologics or surgery. Secondary outcomes included CRP, HBI/SCCAI, steroid withdrawal and adverse events.

RESULTS

In total, 166 LDAA and 118 AZAm patients (median follow-up 25 and 27 months) were evaluated. Clinical benefit was more frequently observed in LDAA patients at 6 months (74% vs. 53%, p = 0.0003), 12 months (54% vs. 37%, p = 0.01) and in the long-term (median 36 months; 37% vs. 24%, p = 0.04). Throughout follow-up, AZAm patients were 60% more likely to fail therapy, due to a higher intolerance rate (45% vs. 26%, p = 0.001). Only 73% of the effective AZA dose was tolerated in AZAm patients, while LDAA could be initiated and maintained at its target dose. Incidence of myelotoxicity and elevated liver enzymes was similar in both cohorts, and both conditions led to LDAA withdrawal in only 2%. Increasing allopurinol from 100 to 200-300 mg/day significantly lowered liver enzymes in 5/6 LDAA patients with hepatotoxicity.

CONCLUSIONS

Our poor AZAm outcomes emphasize that optimization of azathioprine is needed. We demonstrated a long-term safe and more effective profile of first-line LDAA. This co-therapy may therefore be considered standard first-line immunosuppressive.

5-Aminosalicylic Acid Chemoprevention in Inflammatory Bowel Diseases: Is It Necessary in the Age of Biologics and Small Molecules?

BACKGROUND

Due to the increased incidence of colorectal cancer in inflammatory bowel diseases (IBDs), the value of chemoprevention for this patient group has been repeatedly debated in the past decade. This review describes available evidence and the current recommendations for chemoprevention in national and international guidelines IBD guidelines.

SUMMARY

5-Aminosalicylic acid (5-ASA) compounds are the preferred therapeutic option for mild to moderate ulcerative colitis (UC). Aside from the known anti-inflammatory effects, their chemopreventive abilities have been described in vitro and in vivo. Pooling the increasing number of retrospective and population-based clinical studies over the last 15 years, 7 consecutive meta-analyses revealed partially conflicting results for the chemopreventive efficacy of 5-ASA, and thus, not all IBD guidelines currently recommend chemoprevention with mesalamine compounds. Accumulating evidence for decreasing the colorectal cancer (CRC) risk in support of thiopurines more recently shows a protective effect. This effect seems solely mediated by control of intestinal inflammation since, for this drug class, another mechanistic interference in IBD-associated CRC pathogenesis is not known. The results regarding chemopreventive efficacy for ursodeoxycholic acid or folic acid are equivocal, and the use of these medications to prevent CRC is not firmly established. Like UC, the risk of CRC is also significantly increased in patients with Crohn's disease (CD), especially Crohn's colitis. However, no published studies exclusively assess the effects of surveillance on the early detection of cancer or CRC chemoprevention in CD patients. In meta-analyses, which predominantly included UC patients, 5-ASA or thiopurines were not beneficial in small CD subgroups. The level of evidence for anti-TNFα agents, anti-integrin (e.g., vedolizumab), or anti-IL-12/IL-23 agents (e.g., ustekinumab) and Janus kinase inhibitors is currently too low or nonexistent to use them solely for chemoprevention in UC or CD patients.

KEY MESSAGE

Intestinal inflammation is one of the main risk factors for developing CRC in IBD, and all drugs that induce and maintain mucosal healing most likely also decrease the IBD-associated CRC risk. Thus, a therapeutic strategy of adding a 5-ASA therapy to a successfully mucosal healing-inducing therapy, for example, with a biologic or a small molecule merely to prevent CRC appears to be obsolete.

The association between pre-colectomy thiopurine use and risk of neoplasia after ileal pouch anal anastomosis in patients with ulcerative colitis or indeterminate colitis: a propensity score analysis

BACKGROUND

The risk of neoplasia of the pouch or residual rectum in patients with ulcerative colitis (UC) who undergo total proctocolectomy (TPC) with ileal pouch anal anastomosis (IPAA) is incompletely investigated. Thiopurine use is associated with a reduced risk of colorectal neoplasia in patients with UC. We tested the hypothesis that thiopurine use prior to TPC may be associated with a reduced risk of primary neoplasia after IPAA.

METHODS

We conducted a retrospective cohort analysis of patients from a tertiary referral center from January 2008 to December 2017. Eligible patients with UC or IC underwent TPC with IPAA and had at least two pouchoscopies with biopsies ≥ 6 months after surgery. Propensity score analysis was conducted to match thiopurine exposed vs unexposed groups based on clinical covariates. Multivariable Cox regression analysis estimated the risk of neoplasia.

RESULTS

A total of 284 patients with UC or IC (57.4% male, median age 35.6 years) were analyzed. Ninety-seven patients (34.2%) were confirmed to have thiopurine exposure ≥ 12 weeks immediately prior to TPC ("exposed") and 187 (65.8%) were confirmed to have no thiopurine exposure for at least 365 days prior to TPC ("non-exposed"). Compared to non-exposed patients, patients with thiopurine exposure less often had dysplasia (7.2% vs 23.0%, p = 0.001) and had lower grades of dysplasia before colectomy. After IPAA, patients with neoplasia were older (44.0 vs 34.8 years, p = 0.03), more likely to have had dysplasia as colectomy indication (44.4% vs 15.4%, p = 0.007), and more likely to require pouch excision (55.6% vs 10.2%, p < 0.0001), compared to patients without neoplasia. On propensity-matched cohort analysis, no factors were significantly associated with risk of primary neoplasia.

CONCLUSION

Thiopurine exposure for at least the 12 weeks prior to TPC in patients with UC or IC does not appear to be independently associated with risk of primary neoplasia following IPAA.

The Role of the Immune System in IBD-Associated Colorectal Cancer: From Pro to Anti-Tumorigenic Mechanisms

Patients with inflammatory bowel disease (IBD) have increased incidence of colorectal cancer (CRC). IBD-associated cancer follows a well-characterized sequence of intestinal epithelial changes, in which genetic mutations and molecular aberrations play a key role. IBD-associated cancer develops against a background of chronic inflammation and pro-inflammatory immune cells, and their products contribute to cancer development and progression. In recent years, the effect of the immunosuppressive microenvironment in cancer development and progression has gained more attention, mainly because of the unprecedented anti-tumor effects of immune checkpoint inhibitors in selected groups of patients. Even though IBD-associated cancer develops in the background of chronic inflammation which is associated with activation of endogenous anti-inflammatory or suppressive mechanisms, the potential role of an immunosuppressive microenvironment in these cancers is largely unknown. In this review, we outline the role of the immune system in promoting cancer development in chronic inflammatory diseases such as IBD, with a specific focus on the anti-inflammatory mechanisms and suppressive immune cells that may play a role in IBD-associated tumorigenesis.

Inflammatory Bowel Disease and Risk of Colorectal Cancer: An Overview From Pathophysiology to Pharmacological Prevention

Increased risk of colorectal cancer (CRC) in inflammatory bowel disease (IBD) patients has been attributed to long-standing chronic inflammation, with the contribution of genetic alterations and environmental factors such as the microbiota. Moreover, accumulating data indicate that IBD-associated CRC (IBD-CRC) may initiate and develop through a pathway of tumorigenesis distinct from that of sporadic CRC. This mini-review summarizes the current knowledge of IBD-CRC, focusing on the main mechanisms underlying its pathogenesis, and on the important role of immunomodulators and biologics used to treat IBD patients in interfering with the inflammatory process involved in carcinogenesis.

Surveillance and management of colorectal dysplasia and cancer in inflammatory bowel disease: Current practice and future perspectives

Patients with inflammatory bowel disease (IBD) are at increased risk of developing colorectal cancer (CRC). Current guidelines recommend frequent surveillance colonoscopies for patients with at least left-sided ulcerative colitis, or Crohn's disease involving more than 30% of the colon. Surveillance allows for early detection and treatment of colorectal dysplasia and cancer. The first colonoscopy should be performed 8 to 10 years after onset of disease symptoms. European and British guidelines employ a risk-stratification algorithm that assigns patients to surveillance intervals of one, three or five years, whereas American guidelines recommend to perform surveillance every 1 to 3 years based on the (combined) presence of risk factors. Patients with concomitant primary sclerosing cholangitis are at an additionally increased risk, and should undergo annual surveillance starting immediately after the diagnosis. The current practice of surveillance is based on limited evidence, is resource intensive and cannot preclude the occurrence of interval carcinomas. Fortunately, advances in endoscopic techniques for mucosal visualisation, along with better control of inflammation, have resulted in a declining incidence of CRC in patients with IBD. Furthermore, advanced endoscopic resection techniques can be expected to result in a shift from surgical to endoscopic management of dysplastic lesions. In this review, we provide an up-to-date overview of colitis-associated CRC pathophysiology, epidemiology, surveillance practices, and management of dysplasia.

Lower Rates of Colorectal Cancer in Patients With Inflammatory Bowel Disease Using Anti-TNF Therapy

BACKGROUND

Chronic inflammation is a key factor for the development of colorectal cancer (CRC) among patients with inflammatory bowel disease (IBD). Despite the increased use of biologic agents in patients with IBD, their impact on colorectal carcinogenesis remains unclear. With the use of a large database, we sought to describe the effect of biologics on CRC among patients with IBD.

METHODS

We evaluated a multicenter database (Explorys) consisting of electronic medical records from several U.S. hospitals between 1999 and 2020. A cohort of patients with a diagnosis of IBD was identified. We performed a multivariate analysis to adjust for multiple factors including medical and surgical therapies.

RESULTS

There were a total of 62,007,510 patients in the database between 1999 and 2020. Amongst those, 225,090 (0.36%) individuals had Crohn's disease and 188,420 (0.30%) had ulcerative colitis. After adjusting for confounding factors using multivariate analysis, patients with IBD were more likely to develop CRC. Among the IBD cohort, patients treated with anti-TNF agents were less likely to develop CRC; patients with Crohn's disease: odds ratio, 0.69; 95% confidence interval, 0.66-0.73; P < 0.0001 vs patients with ulcerative colitis: odds ratio, 0.78; 95% confidence interval, 0.73-0.83; P < 0.0001.

CONCLUSIONS

Patients with IBD who were treated with anti-tumor necrosis factor agents were less likely to develop CRC. Prospective studies are needed to evaluate whether anti-tumor necrosis factor drugs provide a chemoprotective effect in patients with IBD by inflammation control and mucosal healing.

Predicting Colorectal Cancer Occurrence in IBD

Patients with colonic inflammatory bowel disease (IBD) are at an increased risk of developing colorectal cancer (CRC), and are therefore enrolled into a surveillance programme aimed at detecting dysplasia or early cancer. Current surveillance programmes are guided by clinical, endoscopic or histological predictors of colitis-associated CRC (CA-CRC). We have seen great progress in our understanding of these predictors of disease progression, and advances in endoscopic technique and management, along with improved medical care, has been mirrored by the falling incidence of CA-CRC over the last 50 years. However, more could be done to improve our molecular understanding of CA-CRC progression and enable better risk stratification for patients with IBD. This review summarises the known risk factors associated with CA-CRC and explores the molecular landscape that has the potential to complement and optimise the existing IBD surveillance programme.

Temporal trend in inpatient mortality in inflammatory bowel disease-associated colorectal cancer vs non-inflammatory colorectal cancer: a nationwide retrospective study

BACKGROUND

Early detection and advancement in therapy have successfully achieved a steady decrease in colorectal cancer (CRC) mortality over the last two decades. On the other hand, studies investigating mortality trends in inflammatory bowel disease-associated CRC (IBD-CRC) are scarce and inconclusive. We conducted a retrospective analysis aiming to identify differences between inpatient mortality trends in IBD-CRC vs non-IBD-CRC and possible contributing factors.

METHODS

The National Inpatient Sample (NIS) database from 2006-2014 was queried to identify all patients admitted with a diagnosis of CRC. The main outcome was the prevalence and trend of mortality among IBD-CRC and non-IBD-CRC. The secondary outcome was the evaluation of predictors of inpatient mortality.

RESULTS

A total of 1,190,759 weighted cases with the admission diagnosis of CRC were included in the study. Of which 10,997 (0.9%) had a co-diagnosis of IBD. The population with non-IBD-CRC had a statistically significant downward temporal trend in mortality (p < 0.001), while patients with IBD-CRC did not have any statistically significant temporal trend in inpatient mortality (p = 0.067). After subgroup analysis, patients with Crohn's disease-CRC had an upward temporal trend in mortality (p = 0.183) compared to patients with ulcerative colitis-CRC with a downward trend in mortality (p = 0.001). Sepsis resulted to be a stronger predictor of mortality for CD-CRC, while VTE for UC-CRC.

CONCLUSION

Multiples strategies established to prevent morbidity and mortality in CRC have been fruitful in non-IBD-CRC population, but have not been enough for IBD-CRC population to cause the same effect. Further strategies are needed to achieve a reduction in IBD-CRC mortality trend.

Effects of 5-aminosalicylates or thiopurines on the progression of low-grade dysplasia in patients with inflammatory bowel disease: a systematic review and meta-analysis

PURPOSE

Although 5-aminosalicylates and thiopurines may have an antineoplastic effect on colorectal neoplasia in patients with inflammatory bowel disease (IBD), their impact on the progression of low-grade dysplasia (LGD) in IBD is uncertain. Therefore, we performed a systematic review and meta-analysis to evaluate whether 5-aminosalicylates or thiopurines can protect against the progression of LGD in patients with IBD.

METHODS

Systematic searches of PubMed, EMBASE, Cochrane Library databases, and major conference proceedings were conducted to identify all eligible studies through March 2020. Data were pooled using a random effects model. Study quality was assessed using the Newcastle-Ottawa Scale.

RESULTS

Five studies comprising 776 IBD patients with LGD were included. Overall, 5-aminosalicylates (Hazard ratio (HR) = 0.91, 95% confidence interval (CI) 0.55-1.51) and thiopurines (HR = 0.64, 95% CI 0.23-1.79) did not significantly reduce the risk of advanced colorectal neoplasia (high-grade dysplasia/cancer) in IBD patients with LGD. Moreover, the effects of 5-aminosalicylates or thiopurines on risk of advanced colorectal neoplasia in IBD patients with LGD were not significant by different primary sclerosing cholangitis status, study quality, sample size, and IBD type.

CONCLUSIONS

In this study, we did not find a significant protective effect of 5-aminosalicylates or thiopurines on the progression of LGD in patients with IBD.

Thiopurines and non-melanoma skin cancer: partners in crime in inflammatory bowel diseases

INTRODUCTION

Several studies have shown that inflammatory bowel diseases (IBD) patients treated with thiopurines have an increased risk of developing skin cancer.

SOURCES OF DATA

This review is based on recent published literature regarding the use of thiopurines in IBD and skin malignancies.

AREAS OF AGREEMENT

Exposure to thiopurines is significantly associated with nonmelanoma skin cancer, but not with melanoma. Primary and secondary prevention including sun-protective measures and regular dermatologic screening are recommended in IBD patients, particularly in those exposed to thiopurines.

AREAS OF CONTROVERSY

Both when and how immunosuppressive therapy should be resumed in patients with a prior history of skin cancer still remain debatable topics.

GROWING POINTS

The benefit-risk balance between thiopurine therapy and risk of skin cancer should be evaluated in the drug decision process.

AREAS TIMELY FOR DEVELOPING RESEARCH

The approval of new effective strategies requires the re-evaluation of the positioning of thiopurines within the therapeutic algorithm based on an increasingly individualized approach.

Differential regulation of JAK/STAT-signaling in patients with ulcerative colitis and Crohn’s disease

In 2018, the pan-Janus kinase (JAK) inhibitor tofacitinib was launched for the treatment of ulcerative colitis (UC). Although tofacitinib has proven efficacious in patients with active UC, it failed in patients with Crohn’s disease (CD). This finding strongly hints at a different contribution of JAK signaling in both entities. Here, we review the current knowledge on the interplay between the JAK/signal transducer and activator of transcription (STAT) pathway and inflammatory bowel diseases (IBD). In particular, we provide a detailed overview of the differences and similarities of JAK/STAT-signaling in UC and CD, highlight the impact of the JAK/STAT pathway in experimental colitis models and summarize the published evidence on JAK/STAT-signaling in immune cells of IBD as well as the genetic association between the JAK/STAT pathway and IBD. Finally, we describe novel treatment strategies targeting JAK/STAT inhibition in UC and CD and comment on the limitations and challenges of the new drug class.

Review article: withdrawal of 5-aminosalicylates in inflammatory bowel disease

BACKGROUND

5-aminosalicylates (5-ASA) are widely used in inflammatory bowel disease (IBD), but emerging evidence suggests that they may be safely withdrawn in significant subsets of patients. This is important to address: 5-ASA therapy accounts for up to 25% of total healthcare costs in ulcerative colitis (UC), while almost a third of patients with Crohn's disease (CD) receive long-term 5-ASA despite no clear evidence of benefit. Further, rationalising medication burden may improve overall adherence and outcome.

AIMS

To summarise the rationale for 5-ASA withdrawal, review the current evidence in both UC and CD and consider the data surrounding colorectal cancer (CRC) prevention, guiding an evidence-based withdrawal strategy.

METHODS

PubMed was searched to identify relevant studies. Only papers published in English were reviewed, with priority given to randomised clinical trials and meta-analyses.

RESULTS

For patients with UC, consideration of 5-ASA withdrawal should be made on a case-by-case basis, but it appears safest for those in deep remission without any of the following risk factors: younger age (<40 years), remission for less than 2 years, a history of multiple flares, extensive disease. 5-ASA withdrawal should also be considered in patients with UC escalated to biologic therapy who have achieved remission and in all patients with CD. Although 5-ASA therapy may have chemopreventive benefits for CRC, the cost-benefit ratio appears significant, and this indication is not justified by evidence in those who have achieved remission and are continuing therapy with other agents, or in those in sustained remission without a history of extensive disease.

CONCLUSIONS

Although the majority of patients with IBD receive 5-ASA during their disease course, safe withdrawal appears possible in many, with important implications for both health economics and patient experience. A number of unanswered questions, however, remain.

Limited added value of laboratory monitoring in thiopurine maintenance monotherapy in inflammatory bowel disease patients

BACKGROUND

To timely detect myelotoxicity and hepatotoxicity, laboratory monitoring at 3-month intervals is advised throughout thiopurine maintenance treatment for IBD. However, reported incidence rates of myelotoxicity and hepatotoxicity in maintenance treatment are low.

AIM

To assess incidence rates and clinical consequences of myelotoxicity and hepatotoxicity in thiopurine maintenance therapy after at least 1 year of thiopurine treatment.

METHODS

Retrospective analysis of therapy adjustment for laboratory toxicity in adult IBD patients after 12 consecutive months of azathioprine (AZA) or mercaptopurine monotherapy (ie baseline) between 2000 and 2016. Incidence rates of laboratory toxicity (ie myelotoxicity [leucocyte count <4.0 × 10e9/L, and/or platelet count <150 × 10e9/L] and/or hepatotoxicity (gamma-glutamyltransferase [GGT], alkaline phosphatase [AP], ALT and/or AST above ULN, excluding isolated increased AST/AP]) and associated diagnostic procedures and complications were assessed.

RESULTS

In total, 12,391 laboratory assessments were performed on 1132 patients (56% female, AZA 74%) during 3.3 years of median follow-up. Median monitoring frequency was 3.1 assessments/treatment year. Only 83/12,391 (0.7%) assessments resulted in therapy adjustment, dose reduction in 46 patients, cessation in 28 and allopurinol initiation in nine; risk of therapy adjustment was 1.9% per treatment year. Incidence rates of myelotoxicity were 7.1% (5.1% mild/1.8% moderate/0.1% severe) and hepatotoxicity 5.1% (3.8% mild/1.1% moderate/0.2% severe) per treatment year. Treatment-related complications with concurrent laboratory toxicity occurred in 12 patients (1.1%) and would not have been prevented by monitoring.

CONCLUSION

Severe laboratory toxicity is uncommon after 1 year of thiopurine monotherapy at 4-month monitoring intervals. Therapy adjustments are rare after detection of laboratory toxicity. After 1 year of thiopurine monotherapy, laboratory monitoring may be lowered to less than a 4-month interval.

Cancer incidence in Behçet's disease

BACKGROUND

Previous studies demonstrated an increased cancer risk in autoimmune diseases. Behçet's disease (BD) was also reported to be associated with an increased risk of cancer, although the data is limited.

AIMS

In this study, we aimed to assess cancer incidence in a large cohort of BD patients and to compare with the data of the same age and gender groups.

METHODS

The study cohort consisted of BD patients of > 18 years of age who were prospectively recorded in the Hacettepe University Vasculitis Center. Data on any cancer was collected from the patient files. Cancer incidence was compared with age- and gender-specific cancer incidence rates of the normal population retrieved from the 2014 Turkish National Cancer Registry (TNCR) data using standardized incidence rates (SIR).

RESULTS

Totally, 451 adult cases with BD were included. The median age of the cohort was 43 (20-75), and 52.5% of the patients were males. Eleven cancer cases were observed during a median of 124 months follow-up. Behçet's disease was associated with an increase in cancer risk compared with expected counts in the corresponding age and sex group (SIR 2.84, 95% CI 1.50-4.94, p < 0.001). Patients with papulopustular lesions had a trend toward a decreased risk of cancer (p = 0.060), and patients using azathioprine had a significantly decreased cancer risk (p = 0.031).

CONCLUSION

This study revealed BD patients had approximately three times increased cancer risk compared with corresponding age and sex groups. Besides the routine care, increased attention for cancer surveillance is required in the follow-up of BD patients.

Changing patterns in the epidemiology and outcomes of inflammatory bowel disease in the United Kingdom: 2000-2018

BACKGROUND

Data regarding incidence, prevalence and long-term outcomes of inflammatory bowel diseases in the UK are limited or outdated.

AIMS

To investigate incidence and prevalence of Crohn's disease and ulcerative colitis and risk of colorectal cancer and all-cause mortality in these diseases.

METHODS

Inflammatory bowel disease cases between 2000 and 2018 were identified from a national primary care database. Inflammatory bowel disease prevalence was forecast until 2025. The association between inflammatory bowel disease and colorectal cancer and all-cause mortality was investigated using age/sex-matched retrospective cohort studies. Hazard ratios were adjusted for age, sex, deprivation, comorbidity, smoking status and body mass index.

RESULTS

Ulcerative colitis prevalence increased from 390 to 570 per 100 000 population from 2000 to 2017. Prevalence of Crohn's disease increased from 220 to 400 per 100 000. In 2017 male Crohn's disease prevalence was 0.35% (95% confidence interval 0.34-0.36); female prevalence was 0.44% (0.43-0.45). Prevalence of inflammatory bowel disease is predicted to be 1.1% by 2025. Incidence of ulcerative colitis and Crohn's disease was 23.2 (22.8-23.6) and 14.3 (14.0-14.7) per 100 000 person-years respectively. Subjects with ulcerative colitis were more likely to develop colorectal cancer than controls (adjusted Hazard Ratio 1.40 [1.23-1.59]). Colorectal cancer rates remained stable in inflammatory bowel diseases over time. Ulcerative colitis and Crohn's disease were associated with increased risk of all-cause mortality (1.17 [1.14-1.21] and 1.42 [1.36-1.48] respectively).

CONCLUSIONS

The UK prevalence of inflammatory bowel disease is greater than previous reports suggest and we predict an 11% increase in prevalence by the year 2025. Mortality risk in inflammatory bowel disease and colorectal cancer risk in ulcerative colitis are increased compared to matched controls.

Gastrointestinal neoplasia in patients with inflammatory bowel disease: Opportunities to enhance preventative strategies

Background and Aims

Gastrointestinal (GI) adenocarcinoma, especially colorectal cancer (CRC), is a devastating complication of inflammatory bowel disease (IBD). We sought to examine the role of chronic inflammation and other possible predictors of the development of CRC, as well as assess as yet unexamined factors such as psychological comorbidity and engagement in care.

Methods

This study included all patients involved in a tertiary hospital IBD service diagnosed with CRC between 2007 and 2017. Reports from histological specimens were assessed, and all those with adenocarcinoma, high‐grade dysplasia (HGD), or multifocal low‐grade dysplasia (LGD) originating within IBD‐affected mucosa were included in the study.

Results

A total of 32 patients were included in the study (17 with adenocarcinoma and 15 with HGD/multifocal LGD). The majority had a duration of disease >20 years. Eleven patients (34%, CI 20–52%) had previous disease‐related surgery, and 16 (50%, CI 34–66%) had multiple previous disease‐related admissions. Thirteen patients (62%, CI 41–79%) had >50% of CRP results higher than 8 mg/L. Psychiatric comorbidities were common, with 19 patients (59%, CI 42–74%) having a psychiatric comorbidity or poor engagement in treatment.

Conclusion

In this cohort, we have highlighted poor engagement, hesitation to up‐titrate therapy when indicated, and psychological comorbidities as likely contributors to poor disease control and development of GI adenocarcinoma. Based on our data, these easily identifiable clinical care factors should not be overlooked when addressing IBD‐related GI malignancy prevention. Additional research is required to assess a direct causal relationship, but this study would support the incorporation of psychology services into IBD clinics.

The Role of MicroRNAs upon Epithelial-to-Mesenchymal Transition in Inflammatory Bowel Disease

Increasing evidence suggest the significance of inflammation in the progression of cancer, for example the development of colorectal cancer in Inflammatory Bowel Disease (IBD) patients. Long-lasting inflammation in the gastrointestinal tract causes serious systemic complications and breaks the homeostasis of the intestine, where the altered expression of regulatory genes and miRNAs trigger malignant transformations. Several steps lead from acute inflammation to malignancies: epithelial-to-mesenchymal transition (EMT) and inhibitory microRNAs (miRNAs) are known factors during multistage carcinogenesis and IBD pathogenesis. In this review, we outline the interactions between EMT components and miRNAs that may affect cancer development during IBD.

Comparison of outcomes of continuation/discontinuation of 5-aminosalicylic acid after initiation of anti-tumor necrosis factor-alpha therapy in patients with inflammatory bowel disease

BACKGROUND

Few maintenance therapeutic options are available for inflammatory bowel disease (IBD). Data on the effects of continuing 5-aminosalicylic acid (5-ASA) treatment in patients who commence on biologics as maintenance treatment remain scarce. We evaluated IBD patient outcomes after continuation/discontinuation of 5-ASA when biologics were administered as maintenance treatment.

METHODS

We retrospectively reviewed the clinical, laboratory, and imaging data of patients diagnosed with IBD (ulcerative colitis (UC), 763; Crohn's disease (CD), 537) in the Gil Medical Center (GMC) from February 2005 to June 2018. We divided patients administered with biologics as maintenance treatment into those who did and did not continue on 5-ASA and compared the efficacies of the two treatment options using the log-rank test and Cox proportional hazards models.

RESULTS

Of 1300 total IBD patients, 128 (UC, 63; CD, 65) were prescribed biologics as induction and maintenance treatments. The median follow-up period was 109.5 weeks. All cases were divided into those who did or did not combine 5-ASA with biologics as maintenance treatments. Kaplan-Meier analysis showed that the event-free survival (exacerbation of disease activity) of UC patients treated with biologics and 5-ASA (n = 42) was not significantly lower than that of those taking biologics alone (n = 21) (log rank test, P = 0.68). The same was true of CD patients (n = 42, biologics and 5-ASA; n = 23, biologics only) (log rank test, P = 0.87).

CONCLUSIONS

Continuation of 5-ASA after initiation of anti-tumor necrosis factor-alpha agents did not improve prognosis in Korean IBD patients compared with that of those who discontinued 5-ASA during maintenance treatment, particularly in patients who experienced more than two disease aggravations.

Thiopurine Therapy in Patients With Inflammatory Bowel Disease: A Focus on Metabolism and Pharmacogenetics

Thiopurines have been widely used for the maintenance of remission or steroid sparing in patients with inflammatory bowel disease. However, potential drug-related adverse events frequently interfere with their use. Indeed, drug withdrawals associated with adverse reactions have been reported in approximately 25% of patients. To balance the efficacy, safety, and tolerability of thiopurines, regular monitoring of biomarkers (complete blood cell count, liver function test, and metabolic profiles), steady dose escalation, and pretreatment thiopurine S-methyltransferase (TPMT) genotype screening have been routinely recommended. However, the complex thiopurine metabolic pathway and individual differences attributed to pharmacogenetic diversity limit the effectiveness of these strategies in the optimization of thiopurine therapy. Recently, in an effort to facilitate more accurate and personalized prediction of thiopurine response or toxicity, novel genetic markers including NUDT15 and FTO genes were discovered. These discoveries are remarkable because TPMT screening has minimal efficacy for predicting myelosuppression especially in Asian populations, despite the fact that thee populations have a higher frequency of myelosuppression than Western populations. This review focuses on the current understanding of the metabolic pathway and the pharmacogenetics of thiopurines and suggests a personalized preventive strategy against potential adverse drug reactions to optimize their therapeutic application.

Colorectal cancer surveillance in inflammatory bowel disease: Practice guidelines and recent developments

Patients with long-standing inflammatory bowel disease (IBD) involving at least 1/3 of the colon are at increased risk for colorectal cancer (CRC). Advancements in CRC screening and surveillance and improved treatment of IBD has reduced CRC incidence in patients with ulcerative colitis and Crohn’s colitis. Most cases of CRC are thought to arise from dysplasia, and recent evidence suggests that the majority of dysplastic lesions in patients with IBD are visible, in part thanks to advancements in high definition colonoscopy and chromoendoscopy. Recent practice guidelines have supported the use of chromoendoscopy with targeted biopsies of visible lesions rather than traditional random biopsies. Endoscopists are encouraged to endoscopically resect visible dysplasia and only recommend surgery when a complete resection is not possible. New technologies such as virtual chromoendoscopy are emerging as potential tools in CRC screening. Patients with IBD at increased risk for developing CRC should undergo surveillance colonoscopy using new approaches and techniques.

The Evolving Role of Thiopurines in Inflammatory Bowel Disease

PURPOSE OF REVIEW

With the advent of biologic therapies for the treatment of inflammatory bowel disease, the roles of thiopurines have continued to evolve. This review will focus on recent advances in pharmacology and the safety and efficacy of thiopurines as maintenance therapies for steroid-induced remissions and post-surgical maintenance of remission and as combination therapies to reduce immunogenicities of biologic agents.

RECENT FINDINGS

Due to pharmacogenetics of thiopurine S-methyltransferase, thiopurine dosing is more effectively based on monitoring of thiopurine metabolites rather than weight-based dosing. Thiopurines continue to have a role as maintenance therapy after steroid-induced remissions and in combination with biologics to induce and maintain remission. Safety monitoring includes measurements of blood counts, liver chemistries, and dermatologic evaluations and protection from sun exposure. Thiopurines appear to be safe during pregnancies and while very uncommon, lymphomas (including hepatosplenic T cell lymphomas) remain a recognized risk, particularly in younger and older males.

Silibinin Retards Colitis-associated Carcinogenesis by Repression of Cdc25C in Mouse Model

PURPOSE

Silibinin possesses the efficacy of anticancer and anti-inflammation. We aimed to test whether silibinin could prevent colitis-associated carcinogenesis in mouse model.

EXPERIMENTAL DESIGN

Azoxymethane (AOM) and dextran sulfate sodium (DSS) were used to induce colitis-associated tumorigenesis in C57BL mice. Six-to-eight-week-old male mice were gavaged with 350 or 750 mg/kg of silibinin for 10 weeks right after DSS administration. The mice were then sacrificed, and colon tissues were measured for tumor multiplicity and size. Molecular changes about proliferation, apoptosis and inflammation were tested.

RESULTS

Silibinin feeding showed a dose-dependent inhibition on the size of tumor induced by AOM/DSS in mice. In addition, silibinin inhibited cell proliferation evidenced by a decrease (P < 0.05) in Ki-67 and proliferating cell nuclear antigen (PCNA). However, silibinin did not show any significant effect on inflammation, apoptosis, and the mRNA expression of cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), and vascular endothelial growth factor (VEGF). The experiments in vitro showed that silibinin induced cell cycle arrest at G2/M phase in CT-26 cells, a mouse colonic cancer cell line. Furthermore, silibinin reduced the expression of Cdc25C and blocked the dephosphorylation of CDK1 at multiple sites both in vitro and in vivo.

CONCLUSIONS

Silibinin targets Cdc25C/CDK1 pathway and mitigates colitis-associated tumorigenesis in mice. Thus, our findings indicate the chemopreventive potential of silibinin for inflammation-associated colon cancer.

ACG Clinical Guideline: Ulcerative Colitis in Adults

Ulcerative colitis (UC) is an idiopathic inflammatory disorder. These guidelines indicate the preferred approach to the management of adults with UC and represent the official practice recommendations of the American College of Gastroenterology. The scientific evidence for these guidelines was evaluated using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) process. In instances where the evidence was not appropriate for GRADE, but there was consensus of significant clinical merit, "key concept" statements were developed using expert consensus. These guidelines are meant to be broadly applicable and should be viewed as the preferred, but not only, approach to clinical scenarios.