Immune checkpoint inhibitor-induced colitis: A comprehensive review

Early identification and multidisciplinary management of immune checkpoint inhibitors associated colitis can improve patient outcomes

Currently, the use of immune checkpoint inhibitors (ICIs) has shown notable clinical efficacy in treating various malignant tumors, significantly improving patient prognosis. However, while ICIs enhance the body’s anti-tumor effects, they can also trigger immune-related adverse events (irAEs), with ICI-associated colitis being one of the more prevalent forms. This condition can disrupt treatment, necessitate drug discontinuation, and adversely affect therapeutic outcomes. In severe cases, irAEs may even become life-threatening. A recent case report by Hong et al highlights the importance of vigilance for ICI-associated colitis in patients experiencing symptoms such as diarrhea and abdominal pain, which can arise both during and even after completion of ICI treatment. Early identification, multidisciplinary management, and continuous monitoring of patients are essential steps to further improve outcomes.

Baseline colitogenicity and acute perturbations of gut microbiota in immunotherapy-related colitis

Immunotherapy-related colitis (irC) frequently emerges as an immune-related adverse event during immune checkpoint inhibitor therapy and is presumably influenced by the gut microbiota. We longitudinally studied microbiomes from 38 ICI-treated cancer patients. We compared 13 ICI-treated subjects who developed irC against 25 ICI-treated subjects who remained irC-free, along with a validation cohort. Leveraging a preclinical mouse model, predisease stools from irC subjects induced greater colitigenicity upon transfer to mice. The microbiota during the first 10 days of irC closely resembled inflammatory bowel disease microbiomes, with reduced diversity, increased Proteobacteria and Veillonella, and decreased Faecalibacterium, which normalized before irC remission. These findings highlight the irC gut microbiota as functionally distinct but phylogenetically similar to non-irC and healthy microbiomes, with the exception of an acute, transient disruption early in irC. We underscore the significance of longitudinal microbiome profiling in developing clinical avenues to detect, monitor, and mitigate irC in ICI therapy cancer patients.

Cross-sectional imaging of mimics of inflammatory bowel disease: not everything is Crohn's disease or ulcerative colitis

Acute and chronic bowel pathologies can often be mistaken for manifestations of inflammatory bowel disease (IBD), and there are many entities with imaging and clinical features that overlap with IBD, making diagnosis difficult. We describe multiple inflammatory, infectious, neoplastic, and vascular entities with imaging and clinical features that may mimic IBD, and highlight differentiating features to assist in diagnosis.

Incidence and risk factors of immune checkpoint inhibitor-induced colitis in Korean patients with cancer

BACKGROUND/AIMS

Immune checkpoint inhibitors (ICIs) are effective in treating cancer. However, various immune-related adverse events (irAEs) have become prevalent, with ICI-induced colitis being the most common gastrointestinal irAE. Thus, we aimed to investigate the incidence and risk factors of ICI-induced colitis in Korean patients with cancer.

METHODS

This retrospective study included patients treated with ICIs between October 2015 and June 2022 in two tertiary referral centers in Daegu, Korea. The incidence of ICI-induced colitis was determined using electronic medical records. Risk factors for ICI-induced colitis were identified using univariate and multivariate logistic regression analyses.

RESULTS

We included 1,478 patients with ICI-treated cancer. The incidence of ICI-induced colitis was 3.5% (n = 52/1,478). Multivariate logistic regression analysis showed that the combination of nivolumab and ipilimumab was a risk factor for ICI-induced colitis (p = 0.006; odds ratio, 9.768; 95% confidence interval, 1.93-49.30).

CONCLUSION

ICI-induced colitis had an incidence rate of 3.5% and was associated with the combination of nivolumab and ipilimumab. Most patients with ICI-induced colitis developed mild symptoms that improved with supportive care alone, making ICI therapy resumption possible.

Immune checkpoint inhibitor-associated gastrointestinal adverse events in patients with colorectal cancer

Background

Immune checkpoint inhibitors (ICI) target microsatellite instability-high (MSI-H) tumors with success. The incidence and characteristics of ICI-related colitis (IMC) in patients with MSI-H colorectal cancers (CRC) are unclear.

Methods

We performed a retrospective analysis of adult patients with CRC who received ICI between June 1, 2014, and December 31, 2022, including data on IMC observed up to 3 months after the last dose of ICI. Patients' demographics, oncologic profile, endoscopic features, treatment and clinical outcomes were evaluated.

Results

Of 474 patients with CRC receiving ICI during our study period, 18 developed IMC (3.8%). The majority were Caucasian (88.8%), male (61.1%), and their median age was 69.5 years. Of these patients, 50% received combination therapy with anti-PD-1/L1 and CTLA-4; 66.6% had MSI-H colorectal cancer, 11.1% had a second cancer-melanoma, while 61.2% and 66.7% had grade 1-2 colitis and diarrhea respectively. Endoscopic evaluation was used in 5 patients, of whom 2 had ulcerative inflammation necessitating selective immunosuppressive therapy with biologics. Therapy was withheld in 61.1% because of toxicity; 41.4% and 5.8% were noted to have median Common Terminology Criteria for Adverse Events grade 2 liver and pancreas toxicity respectively. The majority of our cohort received steroid therapy.

Conclusions

The lower severity of IMC, compared to toxicity in other ICI-treated cancers, may be influenced by the tumor microenvironment in MSI-H colorectal cancer after ICI exposure. Larger prospective studies are necessary to determine the role of tumor biology and the gut microbiome in the disease profile and severity of IMC.

Treatment of immune checkpoint inhibitor-related colitis: a narrative review

Background and Objective

Cancer is one of the most difficult diseases facing modern medicine, and increasing amounts of research and clinical treatments are being applied to the treatment of cancer. Immunotherapy, particularly immune checkpoint inhibitor (ICI) therapy, has revolutionized the treatment and overall survival of patients with several different types of cancer. Approximately one-third of patients treated with ICIs may experience immune-related adverse events (irAEs). Immune checkpoint inhibitor-associated colitis (ICIC) is the most common irAE with an incidence of approximately 8-10%, ICIC usually presents as watery or bloody diarrhea, and if the symptoms are severe, ICI treatment must be interrupted or even terminated. This review summarizes the epidemiology, pathogenesis, clinical characteristics, and therapies of ICIC, focusing on the use of biologics, in order to propose treatment options in different situations to control immune checkpoint inhibitor-related colitis as soon as possible.

Methods

To find relevant articles for this narrative review paper, a combination of keywords such as immune checkpoint inhibitor-related colitis, corticosteroids, biologics were searched for in PubMed databases.

Key Content and Findings

The pathogenesis of ICIC is complex and primarily involves antitumor effects and indirect damage to colonic tissues, as well as the activation of specific proinflammatory pathways. Corticosteroids (CSs) are the first line of treatment for ICIC, but steroid-refractory or steroid-resistant cases often occur. Patients with irAE colitis respond favorably to biologics, and patients with CS-resistant/refractory enterocolitis can benefit from the early use of biologics.

Conclusions

Biologics are currently recommended for the treatment of ICIC but are usually used as a supplement after the failure of first-line CS therapy. Patients with irAE colitis respond favorably to biologics, and patients with CS-resistant/refractory enterocolitis can benefit from the early use of biologics. Biologics (alone or in combination with CS) should be considered as an early therapy option for high-risk patients rather than just an escalation after a failure to respond to CS.

Inflammation-targeted delivery of Urolithin A mitigates chemical- and immune checkpoint inhibitor-induced colitis

Inflammatory bowel disease (IBD) treatment often involves systemic administration of anti-inflammatory drugs or biologics such as anti-TNF-α antibodies. However, current drug therapies suffer from limited efficacy due to unresponsiveness and adverse side effects. To address these challenges, we developed inflammation-targeting nanoparticles (ITNPs) using biopolymers derived from the gum kondagogu (Cochlospermum gossypium) plant. These ITNPs enable selective drug delivery to inflamed regions, offering improved therapeutic outcomes. We designed ITNPs that specifically bind to inflamed regions in both human and mouse intestines, facilitating more effective, uniform, and prolonged drug delivery within the inflamed tissues. Furthermore, we demonstrated that oral administration of ITNPs loaded with urolithin A (UroA), a microbial metabolite or its synthetic analogue UAS03 significantly attenuated chemical- and immune checkpoint inhibitor- induced colitis in pre-clinical models. In conclusion, ITNPs show great promise for delivering UroA or its analogues while enhancing therapeutic efficacy at lower doses and reduced frequency compared to free drug administration. This targeted approach offers a potential solution to enhance IBD treatment while minimizing systemic side effects.

Peptic ulcer induced by immune checkpoint inhibitors successfully treated with glucocorticoids: A report of three cases and a literature review

In recent decades, immune checkpoint inhibitors (ICIs) have emerged as safer and less disruptive alternatives to conventional chemotherapy and radiotherapy for certain patients with tumours. ICIs serve a synergistic role alongside conventional therapies by manipulating the immune system to recognise and target tumour cells. However, excessive activation of the immune system can lead to immune-related adverse events including pneumonia, myocarditis and colitis, which pose serious and even fatal risks. In the present case series, three patients with a thoracic tumour with an ICI-induced peptic ulcer triggered by programmed cell death protein 1 antibodies (diagnosed by gastrointestinal endoscopy) are presented. These cases were successfully treated with corticosteroids. The diagnostic and treatment processes undertaken for these patients underscore the requirement to comprehensively understand the mechanism of ICI-induced peptic ulcer. Moreover, the relevant literature was also reviewed in the present study.

Quality of life under treatment with the immune checkpoint inhibitors ipilimumab and nivolumab in melanoma patients. Real-world data from a prospective observational study at the Skin Cancer Center Kiel

PURPOSE

Combined immunotherapy (ipilimumab + nivolumab) has improved survival in stage IV melanoma patients, making Health-related Quality of Life (HrQoL) crucial due to potential immune-related adverse events (irAEs). Previous studies treated HrQoL as secondary/explorative endpoint, and no specific HrQoL questionnaire for melanoma patients on immune checkpoint inhibitor (ICI) therapy exists. This study aimed to gather specific HrQoL data during combined ICI therapy, tracking changes during and after treatment, and examining associations with gender, irAEs, and treatment response.

METHODS

35 melanoma patients (22 males, 13 females) undergoing combined ICI were surveyed using the Short-form 36 questionnaire (SF-36), the Inflammatory Bowel Disease Questionnaire - Deutsch (IBDQ-D), and the distress thermometer (DT). HrQoL was evaluated during treatment, after six months, and at the onset of autoimmune colitis.

RESULTS

irAEs occurred in 51.4% of patients, with colitis being the most common (26.1%). 45.7% had progressive disease. SF-36 showed stable HrQoL during treatment and follow-up. Women had worse HrQoL on the physical component scale than men (p = 0.019). Patients with progression showed worse HrQoL over time in physical (p = 0.015) and mental health scales (p = 0.04). IBDQ-D showed constant HrQoL throughout treatment and follow-up. Distress on DT remained constant, with women reporting higher levels of distress.

CONCLUSION

HrQoL remained stable during and after therapy. Female gender and disease progression negatively impacted HrQoL. The development of irAEs was not associated with HrQoL, though this may not apply to severe irAEs like colitis, which were not assessed.

An injectable subcutaneous colon-specific immune niche for the treatment of ulcerative colitis

As a chronic autoinflammatory condition, ulcerative colitis is often managed via systemic immunosuppressants. Here we show, in three mouse models of established ulcerative colitis, that a subcutaneously injected colon-specific immunosuppressive niche consisting of colon epithelial cells, decellularized colon extracellular matrix and nanofibres functionalized with programmed death-ligand 1, CD86, a peptide mimic of transforming growth factor-beta 1, and the immunosuppressive small-molecule leflunomide, induced intestinal immunotolerance and reduced inflammation in the animals' lower gastrointestinal tract. The bioengineered colon-specific niche triggered autoreactive T cell anergy and polarized pro-inflammatory macrophages via multiple immunosuppressive pathways, and prevented the infiltration of immune cells into the colon's lamina propria, promoting the recovery of epithelial damage. The bioengineered niche also prevented colitis-associated colorectal cancer and eliminated immune-related colitis triggered by kinase inhibitors and immune checkpoint blockade.

Reconceptualization of immune checkpoint inhibitor-associated gastritis

In recent years, with the extensive application of immunotherapy in clinical practice, it has achieved encouraging therapeutic effects. While enhancing clinical efficacy, however, it can also cause autoimmune damage, triggering immune-related adverse events (irAEs). Reports of immunotherapy-induced gastritis have been increasing annually, but due to its atypical clinical symptoms, early diag-nosis poses a certain challenge. Furthermore, it can lead to severe complications such as gastric bleeding, elevating the risk of adverse outcomes for solid tumor patients if immunotherapy is interrupted. Therefore, gaining a thorough under-standing of the pathogenesis, clinical manifestations, diagnostic criteria, and treatment of immune-related gastritis is of utmost importance for early identification, diagnosis, and treatment. Additionally, the treatment of immune-related gastritis should be personalized according to the specific condition of each patient. For patients with grade 2-3 irAEs, restarting immune checkpoint inhibitors (ICIs) therapy may be considered when symptoms subside to grade 0-1. When restarting ICIs therapy, it is often recommended to use different types of ICIs. For grade 4 irAEs, permanent discontinuation of the medication is necessary.

Immune checkpoint inhibitor-induced diarrhea and colitis: an overview

Immune checkpoint inhibitors (ICIs) have emerged as an integral component of the management of various cancers and have contributed to significant improvements in overall survival. Most available ICIs target anti-cytotoxic T-lymphocyte-associated protein 4 (anti-CTLA4), and anti-programmed cell death 1/programmed cell death ligand 1 (anti-PD1/PDL1). Gastrointestinal immune-related adverse events remain a common complication of ICIs. The predominant manifestations include diarrhea and colitis, which often manifest concurrently as immune-mediated diarrhea and colitis (IMDC). Risk factors for developing these side effects include baseline gut microbiota, preexisting autoimmune disorders, such as inflammatory bowel disease, and type of neoplasm. The hallmark symptom of colitis is diarrhea which may be accompanied by mucus or blood in stools. Patients may also experience abdominal pain, fever, vomiting, and nausea. If not treated rapidly, ICI-induced colitis can lead to serious life-threatening complications. Current management is based on corticosteroids as first-line, and immunosuppressants like infliximab or vedolizumab for refractory cases. Microbiota transplantation and specific cytokines and lymphocyte replication inhibitors are being investigated. Optimal patient care requires maintaining a balance between treatment toxicity and efficacy, hence the aim of this review is to enhance readers' comprehension of the gastrointestinal adverse events associated with ICIs, particularly IMDC. In addition to identifying the risk factors, we discuss the incidence, clinical presentation, workup, and management options of IMDC.

Immune checkpoint inhibitor colitis, a rising issue in targeted cancer therapy era: A literature review

Research advances in the oncology treatment field have led to the widespread use of immunotherapy. The usage of immune checkpoint inhibitor (ICI) has improved the survival of cancer patients with metastases. This has also led to the rapidly expanding indications for ICI use. However, ICI usage may lead to toxicity, which may be immune-related, in different organ-specific targets. The immune-related adverse events (irAEs) of ICI may lead to increased morbidity, decreased quality of life, and early termination of ICI. The clinical manifestations of irAEs in the gastrointestinal system are variable, ranging from self-limited to life-threatening or fatal events. In this review article, we would like to focus on discussing ICI-induced colitis, which is one of the most common ICI irAEs in the gastrointestinal tract.

Successful management of pre-existing psoriatic arthritis through targeting the IL-23/IL-17 axis in cancer patients receiving immune checkpoint inhibitor therapy: a case series

BACKGROUND

Immune checkpoint inhibitors (ICIs) have significantly improved outcomes for patients with cancer. However, these therapies are associated with adverse events including de novo immune-related adverse events or flare of pre-exiting autoimmune disorders. Up to 80% of patients with cancer and pre-existing psoriasis (PsO) or psoriatic arthritis (PsA) experience PsO/PsA flare after initiating ICIs. Targeting the interleukin (IL)-17/IL-23 axis is a mainstream of the PsO/PsA treatment. However, whether this treatment can effectively control PsO/PsA with ICI exposure while preserving anti-tumour efficacy remains unknown.

CASE REPORTS

We report three patients with PsA and cancer, who received ICIs for their cancer treatment. All patients were male. Two patients had clear cell renal cell carcinoma, and one had melanoma. Two patients received anti-PD-1 antibody monotherapy, while one patient received combined anti-CTLA-4 and PD-1 antibody therapy. One patient had been receiving anti-IL-17A antibody (secukinumab), while the other two patients started anti-IL-17A antibody (ixekizumab) and anti-IL-23 antibody (guselkumab) after their PsA flared up during ICI treatment. Of note, with the anti-IL-17A or anti-IL-23 antibody treatment, their PsA remained in remission, and they well tolerated the ICI therapy. Importantly, all three patients showed persistent tumour responses to ICI therapy, including two complete remissions and one stable disease, respectively.

CONCLUSIONS

These three cases suggest that targeting the IL-17/23 axis may be an effective and safe approach for patients with cancer and pre-existing PsA being considered for ICI therapy.

Atezolizumab-Induced Ulcerative Colitis in Patient with Hepatocellular Carcinoma: Case Report and Literature Review

Background and Objectives: Immune check inhibitor (ICI) colitis is one of most common and adverse side effects of ICI. However, there was no case report of ulcerative colitis (UC)-mimicking colitis after atezolizumab use in hepatocellular carcinoma (HCC) to our knowledge. Materials and Methods: We would like to introduce the case of a patient with Stage IV HCC who complained of abdominal pain, diarrhea and rectal bleeding after two cycles of atezolizumab/bevacizumab chemotherapy and was then diagnosed with UC-mimicking colitis. Results: Endoscopy revealed typical findings of UC, suggesting diagnosis of UC-mimicking colitis. The patient was treated with systemic steroids and oral mesalamine, which significantly improved his symptoms, which were also supported by endoscopic findings. The patient resumed chemotherapy with atezolizumab and bevacizumab without any interruption to the chemotherapy schedule. Conclusions: Early endoscopic evaluation is pivotal to diagnosing UC-mimicking colitis. If diagnosed, UC-based treatments such as steroids and mesalamine should be strongly considered. Given previous reports of inflammatory bowel disease (IBD) flare-ups after immunotherapy, routine lower endoscopy, performed together with upper endoscopy before atezolizumab/bevacizumab therapy, is promising to patients.