Management Considerations for Immune Checkpoint Inhibitor-Induced Enterocolitis Based on Management of Inflammatory Bowel Disease

Novel endoscopic scoring system for immune mediated colitis: a multicenter retrospective study of 674 patients

BACKGROUND AND AIMS

No endoscopic scoring system has been established for immune-mediated colitis (IMC). This study aimed to establish such a system for IMC and explore its utility in guiding future selective immunosuppressive therapy (SIT) use compared to clinical symptoms.

METHODS

This retrospective, international, 14-center study included 674 patients who developed IMC after immunotherapy and underwent endoscopic evaluation. Ten endoscopic features were selected by group consensus and assigned 1 point each to calculate an IMC endoscopic score (IMCES). IMCES cutoffs were chosen to maximize specificity for SIT use. This specificity was compared between IMCESs, and clinical symptoms were graded according to a standardized instrument.

RESULTS

A total of 309 (45.8%) patients received SIT. IMCES specificity for SIT use was 82.8% with a cutoff of 4. The inclusion of ulceration as a mandatory criterion resulted in higher specificity (85.0% for a cutoff of 4). In comparison, the specificity of a Mayo endoscopic subscore of 3 was 74.6%, and the specificity of clinical symptom grading was much lower at 27.4% and 12.3%, respectively. Early endoscopy was associated with timely SIT use (P < .001; r = 0.4084).

CONCLUSIONS

This is the largest multicenter study to devise an endoscopic scoring system to guide IMC management. An IMCES cutoff of 4 has a higher specificity for SIT use than clinical symptoms, supporting early endoscopic evaluation for IMC.

The JAK-STAT Pathway as a Therapeutic Strategy in Cancer Patients with Immune Checkpoint Inhibitor-Induced Colitis: A Narrative Review

Immunotherapy has emerged as a pivotal component in the treatment of various malignancies, encompassing lung, skin, gastrointestinal, and head and neck cancers. The foundation of this therapeutic approach lies in immune checkpoint inhibitors (ICI). While ICIs have demonstrated remarkable efficacy in impeding the neoplastic progression of these tumours, their use may give rise to substantial toxicity, notably in the gastrointestinal domain, where ICI colitis constitutes a significant aspect. The optimal positioning of Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway inhibitors in the therapeutic management of ICI colitis remains unclear. Numerous reports have highlighted notable improvements in ICI colitis through the application of pan-JAK-STAT inhibitors, with tofacitinib, in particular, reporting evident clinical remission of colitis. The precise mechanism by which JAK-STAT inhibitors may impact the pathogenetic process of ICI colitis remains inadequately understood. However, there is speculation regarding their potential role in modulating memory resident CD8+ T lymphocytes. The elucidation of this mechanism requires further extensive and robust evidence, and ongoing JAK-STAT-based trials are anticipated to contribute valuable insights.

Gut microbiome on immune checkpoint inhibitor therapy and consequent immune-related colitis: a review

Immune checkpoint inhibitors have dramatically revolutionized the therapeutic landscape for patients with advanced malignancies. Recently, convincing evidence has shown meaningful influence of gut microbiome on human immune system. With the complex link between gut microbiome, host immunity and cancer, the variations in the gut microbiota may influence the efficacy of immune checkpoint inhibitors. Indeed, some bacterial species have been reported to be predictive for cancer outcome in patients treated with immune checkpoint inhibitors. Although immune checkpoint inhibitors are currently proven to be an effective anti-tumor treatment, they can induce a distinct form of toxicity, termed immune-related adverse events. Immune-related colitis is one of the common toxicities from immune checkpoint inhibitors, and it might preclude the cancer therapy in severe or refractory cases. The manipulation of gut microbiome by fecal microbiota transplantation or probiotics administration has been suggested as one of the methods to enhance anti-tumor effects and decrease the risk of immune-related colitis. Here we review the role of gut microbiome on immune checkpoint inhibitor therapy and consequent immune-related colitis to provide a new insight for better anti-cancer therapy.

Immune-Related Colitis Induced by Camrelizumab: A Case Report

In recent years, immunotherapy has become a major research focus in the field of cancer treatment. Because of its good efficacy and lasting immune response, immune checkpoint inhibitors have benefited the long-term survival of many types of cancer patients. However, overactivation of the immune system may attack normal organs and cause a series of immune related adverse reactions. Among them, due to the high incidence of immune-related colitis, it deserves special attention. Camrelizumab is a programmed cell death 1 (PD-1) inhibitor that was developed by Jiangsu Hengrui Medicine Company. We reported the clinical data of a case of hepatocellular carcinoma with immune-related colitis after treatment with camrelizumab. A 63-year-old man with hepatocellular carcinoma developed diarrhea and hematochezia after receiving 4 cycles of camrelizumab. Endoscopy showed multiple flake congestion and edema in the terminal ileum and total colon mucosa with bright red surface. Pathological evaluation showed chronic inflammation of colonic mucosa. After giving 0.25g bid of enteric-coated sulfasalazine tablets orally for 6 weeks, his colitis improved. Camrelizumab can induce immune-related colitis. Sulfasalazine could be used to reduce adverse reactions of glucocorticoids.

Characteristics of appendicitis after immune checkpoint inhibitor therapy among cancer patients

PURPOSE

Immune checkpoint inhibitor (ICI) therapy has revolutionized cancer care but is associated with immune-related adverse events (irAEs). Recent case reports raised the concern that acute appendicitis may be an irAE. In this study, we sought to describe the disease course of post-ICI therapy appendicitis and its associated complications.

METHODS

Adult patients who had an International Classification of Diseases code for appendicitis within the first 2 years after initiating ICI therapy from January 2010 to April 2021 and who had imaging evidence of appendicitis were studied retrospectively.

RESULTS

13,991 patients were identified who had ICI exposure during the study period, 44 had codes for appendicitis, 10 of whom met the inclusion criteria. Their median age at the time of diagnosis was 59 years. The median time from ICI therapy initiation to appendicitis onset was 188 days. The most common presenting symptoms were abdominal pain (70%) and fever (40%). Abscesses were present in two patients, and a perforation was present in one. All 10 patients received broad-spectrum antibiotics. Five patients needed surgery or interventional radiology drainage. Nine patients had resolution of appendicitis symptoms after treatment.

CONCLUSION

Post-ICI therapy appendicitis is rare but presents similarly to and has similar complications rates as conventional appendicitis. Appendectomy remains the mainstay of treatment, but its use can be limited in cancer patients. The decision to continue ICI therapy remains at the discretion of the clinician. Further studies are needed to bring awareness to and advance the understanding of this clinical entity.

Pharmacological Interventions for the Prevention and Treatment of Immune Checkpoint Inhibitor-Associated Enterocolitis: A Systematic Review

BACKGROUND

Patients treated with immune checkpoint inhibitors (ICIs) may develop ICI-associated enterocolitis, for which there is no approved treatment.

AIMS

We aimed to systematically review the efficacy and safety of medical interventions for the prevention and treatment of ICI-associated enterocolitis.

METHODS

MEDLINE, EMBASE, and the Cochrane Library were searched to identify randomized controlled trials (RCTs), cohort and case-control studies, and case series/reports, evaluating interventions (including corticosteroids, biologics, aminosalicylates, immunosuppressants, and fecal transplantation) for ICI-associated enterocolitis. Clinical, endoscopic, and histologic efficacy endpoints were evaluated. The Grading of Recommendations, Assessment, Development, and Evaluation criteria were used to assess overall quality of evidence.

RESULTS

A total of 160 studies (n = 1514) were included (one RCT, 3 retrospective cohort studies, 156 case reports/case series). Very low quality evidence from one RCT suggests budesonide is not effective for prevention of ICI-associated enterocolitis in ipilimumab-treated patients (relative risk 0.93 [95% confidence interval 0.56, 1.56]). Very low quality evidence suggests that corticosteroids, infliximab, and vedolizumab may be effective for treatment of ICI-associated enterocolitis by inducing clinical response and remission. No validated indices for measuring disease activity were used. Biologic treatment was used in 42% (641/1528) of patients, as reported in 97 studies. ICIs were discontinued in 65% (457/702) of patients, as reported in 63 studies.

CONCLUSIONS

Current treatment recommendations for ICI-associated enterocolitis are based on very low quality evidence, primarily from case reports and case series. Large-scale prospective cohort studies and RCTs are needed to develop prophylactic and therapeutic treatments to minimize interruption or discontinuation of oncological therapies.

Immune‐mediated inflammatory diseases of the gastrointestinal tract: Beyond Crohn's disease and ulcerative colitis

Immune‐mediated inflammatory diseases (IMIDs) are a diverse group of complex inflammatory diseases that result from dysregulated immune pathways and can involve any system of the human body. Inflammatory bowel disease (IBD) is one such disease involving the gastrointestinal (GI) system. With high prevalence in the West and increasing incidence in newly industrialized countries, IBD poses a significant burden on health care. IMIDs of the GI system other than IBD can have similar clinical features, causing diagnostic and therapeutic challenges. Although these disorders share a common pathophysiology, the defects can occur anywhere in the complex network of cytokines, inflammatory mediators, and innate and adaptive systems, leading to unregulated inflammation. Precise knowledge about them will help determine the possible targeted therapy. Thus, it is essential to distinguish these disorders from IBD. This review describes various IMIDs of the GI tract that mimic IBD.

Hallmarks of response, resistance, and toxicity to immune checkpoint blockade

Unprecedented advances have been made in cancer treatment with the use of immune checkpoint blockade (ICB). However, responses are limited to a subset of patients, and immune-related adverse events (irAEs) can be problematic, requiring treatment discontinuation. Iterative insights into factors intrinsic and extrinsic to the host that impact ICB response and toxicity are critically needed. Our understanding of the impact of host-intrinsic factors (such as the host genome, epigenome, and immunity) has evolved substantially over the past decade, with greater insights on these factors and on tumor and immune co-evolution. Additionally, we are beginning to understand the impact of acute and cumulative exposures-both internal and external to the host (i.e., the exposome)-on host physiology and response to treatment. Together these represent the current day hallmarks of response, resistance, and toxicity to ICB. Opportunities built on these hallmarks are duly warranted.

Immune checkpoint inhibitor-mediated colitis in gastrointestinal malignancies and inflammatory bowel disease

Immune checkpoint inhibitors (ICI) have markedly changed the landscape of cancer therapy. By re-invigorating the immune system against tumors, ICI provide novel therapeutic options for a broad variety of malignancies, including many gastrointestinal (GI) cancers. However, these therapies can also induce autoimmune-like side effects in healthy tissue across the body. One of the most common of these side effects is ICI-mediated colitis and diarrhea (IMC). Here, we review the incidence and risk of IMC in ICI therapy, with a focus on what is known regarding IMC in patients with GI malignancies. We also discuss data available on the use of ICI and risk of IMC in patients with pre-existing inflammatory bowel disease, as these patients may have increased risk of IMC due to their underlying intestinal pathology.

PD-L1 upregulation is associated with activation of the DNA double-strand break repair pathway in patients with colitic cancer

Ulcerative colitis (UC) is a DNA damage-associated chronic inflammatory disease; the DNA double-strand break (DSB) repair pathway participates in UC-associated dysplasia/colitic cancer carcinogenesis. The DSB/interferon regulatory factor-1 (IRF-1) pathway can induce PD-L1 expression transcriptionally. However, the association of PD-L1/DSB/IRF-1 with sporadic colorectal cancer (SCRC), and UC-associated dysplasia/colitic cancer, remains elusive. Therefore, we investigated the significance of the PD-L1/DSB repair pathway using samples from 17 SCRC and 12 UC patients with rare UC-associated dysplasia/colitic cancer cases by immunohistochemical analysis. We compared PD-L1 expression between patients with SCRC and UC-associated dysplasia/colitic cancer and determined the association between PD-L1 and the CD8+ T-cell/DSB/IRF-1 axis in UC-associated dysplasia/colitic cancer. PD-L1 expression in UC and UC-associated dysplasia/colitic cancer was higher than in normal mucosa or SCRC, and in CD8-positive T lymphocytes in UC-associated dysplasia/colitic cancer than in SCRC. Moreover, PD-L1 upregulation was associated with γH2AX (DSB marker) and IRF-1 upregulation in UC-associated dysplasia/colitic cancer. IRF-1 upregulation was associated with γH2AX upregulation in UC-associated dysplasia/colitic cancer but not in SCRC. Multicolour immunofluorescence staining validated γH2AX/IRF-1/PD-L1 co-expression in colitic cancer tissue sections. Thus, immune cell-induced inflammation might activate the DSB/IRF-1 axis, potentially serving as the primary regulatory mechanism of PD-L1 expression in UC-associated carcinogenesis.

Repeated Fecal Microbial Transplantations and Antibiotic Pre-Treatment Are Linked to Improved Clinical Response and Remission in Inflammatory Bowel Disease: A Systematic Review and Pooled Proportion Meta-Analysis

The response of patients with inflammatory bowel disease (IBD) to fecal microbial transplantation (FMT) has been inconsistent possibly due to variable engraftment of donor microbiota. This failure to engraft has resulted in the use of several different strategies to attempt optimization of the recipient microbiota following FMT. The purpose of our study was to evaluate the effects of two distinct microbial strategies-antibiotic pre-treatment and repeated FMT dosing-on IBD outcomes. A systematic literature review was designed and implemented in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A medical librarian conducted comprehensive searches in MEDLINE, Embase, Scopus, Web of Science Core Collection, and Cochrane Library on 25 November 2019 and updated on 29 January 2021. Primary outcomes of interest included comparing relapse and remission rates in patients with IBD for a single FMT dose, repeated FMT dosages, and antibiotic pre-treatment groups. Twenty-eight articles (six randomized trials, 20 cohort trials, two case series) containing 976 patients were identified. Meta-analysis revealed that both repeated FMT and antibiotic pre-treatment strategies demonstrated improvements in pooled response and remission rates. These clinical improvements were associated with increases in fecal microbiota richness and α-diversity, as well as the enrichment of several short-chain fatty acid (SCFA)-producing anaerobes including Bifidobacterium, Roseburia, Lachnospiraceae, Prevotella, Ruminococcus, and Clostridium related species.

Challenges in Crohn's Disease Management after Gastrointestinal Cancer Diagnosis

Simple Summary

Crohn’s disease (CD) is a chronic inflammatory bowel disease affecting both young and elderly patients, involving the entire gastrointestinal tract from the mouth to anus. The chronic transmural inflammation can lead to several complications, among which gastrointestinal cancers represent one of the most life-threatening, with a higher risk of onset as compared to the general population. Moreover, diagnostic and therapeutic strategies in this subset of patients still represent a significant challenge for physicians. Thus, the aim of this review is to provide a comprehensive overview of the current evidence for an adequate diagnostic pathway and medical and surgical management of CD patients after gastrointestinal cancer onset.

Abstract

Crohn’s disease (CD) is a chronic inflammatory bowel disease with a progressive course, potentially affecting the entire gastrointestinal tract from mouth to anus. Several studies have shown an increased risk of both intestinal and extra-intestinal cancer in patients with CD, due to long-standing transmural inflammation and damage accumulation. The similarity of symptoms among CD, its related complications and the de novo onset of gastrointestinal cancer raises difficulties in the differential diagnosis. In addition, once a cancer diagnosis in CD patients is made, selecting the appropriate treatment can be particularly challenging. Indeed, both surgical and oncological treatments are not always the same as that of the general population, due to the inflammatory context of the gastrointestinal tract and the potential exacerbation of gastrointestinal symptoms of patients with CD; moreover, the overlap of the neoplastic disease could lead to adjustments in the pharmacological treatment of the underlying CD, especially with regard to immunosuppressive drugs. For these reasons, a case-by-case analysis in a multidisciplinary approach is often appropriate for the best diagnostic and therapeutic evaluation of patients with CD after gastrointestinal cancer onset.

Secondary causes of inflammatory bowel diseases

Inflammatory bowel diseases (IBD), conventionally consist of Crohn’s disease (CD) and ulcerative colitis. They occur in individuals with high risk genotype for the disease in the setting of appropriate environmental factors. The pathogenesis of IBD involves a dysregulated autoimmune response to gut dysbiosis, which in turn is triggered due to exposure to various inciting environmental factors. But there is no clearly defined etiology of IBD and this type of disease is termed as “idiopathic IBD”, “classic IBD”, or “primary IBD”. We reviewed the current medical literature and found that certain etiological factors may be responsible for the development of IBD or IBD-like conditions, and we consider this form of de novo IBD as “secondary IBD”. Currently known factors that are potentially responsible for giving rise to secondary IBD are medications; bowel altering surgeries and transplantation of organs, stem cells or fecal microbiome. Medications associated with the development of secondary IBD include; immunomodulators, anti-tumor necrosis factor alpha agents, anti-interleukin agents, interferons, immune stimulating agents and checkpoint inhibitors. Colectomy can in some cases give rise to de novo CD, pouchitis of the ileal pouch, or postcolectomy enteritis syndrome. After solid organ transplantation or hematopoietic stem cell transplantation, the recipient may develop de novo IBD or IBD flare. Fecal microbiota transplantation has been widely used to treat patients suffering from recurrent Clostridium difficile infection but can also causes IBD flares.

Impacts of High Intra- and Inter-Individual Variability in Tacrolimus Pharmacokinetics and Fast Tacrolimus Metabolism on Outcomes of Solid Organ Transplant Recipients

Tacrolimus is a first-line calcineurin inhibitor (CNI) and an integral part of the immunosuppressive strategy in solid organ transplantation. Being a dose-critical drug, tacrolimus has a narrow therapeutic index that necessitates periodic monitoring to maintain the drug’s efficacy and reduce the consequences of overexposure. Tacrolimus is characterized by substantial intra- and inter-individual pharmacokinetic variability. At steady state, the tacrolimus blood concentration to daily dose ratio (C/D ratio) has been described as a surrogate for the estimation of the individual metabolism rate, where a low C/D ratio reflects a higher rate of metabolism. Fast tacrolimus metabolism (low C/D ratio) is associated with the risk of poor outcomes after transplantation, including reduced allograft function and survival, higher allograft rejection, CNI nephrotoxicity, a faster decline in kidney function, reduced death-censored graft survival (DCGS), post-transplant lymphoproliferative disorders, dyslipidemia, hypertension, and cardiovascular events. In this article, we discuss the potential role of the C/D ratio in a noninvasive monitoring strategy for identifying patients at risk for potential adverse events post-transplant.