Systematic review: colitis associated with anti-CTLA-4 therapy

Immune checkpoint inhibitor-related luminal GI adverse events

The early promising results of the use of immune checkpoint inhibitors in the treatment of selected malignancies has ushered a new era in cancer research and the development of treatment options. With the increasing use of this class of medications, a wide array of adverse events is becoming evident, many of which will be encountered by the gastroenterologist. The second most common adverse event associated with immune checkpoint inhibitors involves the GI tract and includes diarrhea and colitis. These are experienced by up to 50% of patients on these agents. The severity of these events varies greatly and may range from mild to fatal. Therefore, it is important that the gastroenterologist is aware of the spectrum of potential GI adverse events. For this review, we conducted an extensive literature search and compiled all relevant information pertaining to the luminal GI tract. The presentation, approach to the patient with luminal GI adverse reactions, risk stratification, management, challenging populations, endoscopic considerations and findings, and histologic findings are discussed in this review.

Adverse effects of immune-checkpoint inhibitors: epidemiology, management and surveillance

Immune-checkpoint inhibitors (ICIs), including anti-cytotoxic T lymphocyte antigen 4 (CTLA-4), anti-programmed cell death 1 (PD-1) and anti-programmed cell death 1 ligand 1 (PD-L1) antibodies, are arguably the most important development in cancer therapy over the past decade. The indications for these agents continue to expand across malignancies and disease settings, thus reshaping many of the previous standard-of-care approaches and bringing new hope to patients. One of the costs of these advances is the emergence of a new spectrum of immune-related adverse events (irAEs), which are often distinctly different from the classical chemotherapy-related toxicities. Owing to the growing use of ICIs in oncology, clinicians will increasingly be confronted with common but also rare irAEs; hence, awareness needs to be raised regarding the clinical presentation, diagnosis and management of these toxicities. In this Review, we provide an overview of the various types of irAEs that have emerged to date. We discuss the epidemiology of these events and their kinetics, risk factors, subtypes and pathophysiology, as well as new insights regarding screening and surveillance strategies. We also highlight the most important aspects of the management of irAEs.

Immune-mediated Colitis from Dual Checkpoint Inhibitors

Melanoma is a deadly disease with immunotherapy treatment options that emerged in the last few years and have changed the disease outcome. However, it is associated with immune-related toxic effects despite improving survival. We present the case of a 53-year-old woman who had two weeks of diarrhea after she was treated with dual immunotherapy agents for her advanced melanoma. The final workup revealed pancolitis, possibly due to immunotherapy adverse effects. Initial conservative treatment, unfortunately, did not lead to a clinical improvement until a steroid was introduced. We are reporting this case to alert our fellow physicians about the immune-mediated toxicities of the relatively new checkpoint inhibitors.

Immune-Mediated Colitis

PURPOSE OF REVIEW

This review addresses our current knowledge of immune-mediated colitis (IMC) and offers a practical guide to its management.

RECENT FINDINGS

Due to the similarity in clinical, endoscopic, and histologic findings between IMC and inflammatory bowel disease (IBD), gastroenterologists have tailored their approach to IMC management to that of IBD. Immune checkpoint inhibitors (ICIs) are monoclonal antibodies that augment the T-cell anti-tumor response of the immune system and have demonstrated their importance in the treatment of a wide range of malignancies. With the growing benefits of ICIs, there are immune-related adverse events (irAEs) that mirror many known autoimmune diseases. Diarrhea and IMC are the most common and severe irAEs noted. No standardized guidelines exist in the management of these irAEs.

Immune-related adverse events in the gastrointestinal tract: diagnostic utility of upper gastrointestinal biopsies

AIMS

Immune checkpoint inhibitors (ICIs) improve survival across a range of malignancies but are also associated with a spectrum of gastrointestinal (GI) immune-related adverse events (GI-irAEs). The aims of this study were to explore the diagnostic value of gastric and duodenal biopsies and to address considerations in the differential diagnosis.

METHODS AND RESULTS

We identified 39 patients who were treated with ICIs and had a subsequent upper GI biopsy. We recorded clinical data and endoscopic findings, and reviewed their gastric, duodenal and colonic biopsies. Twenty-one (54%) patients were treated with an anti-programmed cell death protein 1 (PD-1)/anti-programmed cell death ligand 1 antibody alone, and 17 (44%) patients were treated with a combination of anti-cytotoxic T-lymphocyte-associated protein-4 and anti-PD-1 antibodies. Thirty-two (82%) patients presented with diarrhoea. Gastric alterations included periglandular inflammation and granulomas, and duodenal changes included villous blunting, intraepithelial lymphocytosis, granulomas, and neutrophilic activity. We recognised four patterns of colonic injury: (i) acute self-limiting colitis; (ii) lymphocytic colitis; (iii) collagenous colitis; and (iv) apoptosis-only. Twenty-nine (74%) and 10 (26%) patients were diagnosed clinically as positive and negative for GI-irAEs, respectively. Gastric periglandular inflammation (P = 0.004) and an increased number of colonic lamina propria mononuclear cells (P = 0.04) correlated with the clinical diagnosis of a GI-irAE. Histological alterations associated with ICI injury were more often identified in upper GI biopsies (71%) than in colonic biopsies (65%).

CONCLUSIONS

The morphological spectrum of ICI-related GI disease is broad, and mimics a range of infectious and inflammatory diseases. Gastric periglandular inflammation represents one of the more characteristic histological features of GI-irAEs. The study underscores the importance of a comprehensive review of upper and lower GI biopsies for the diagnosis of GI-irAEs.

Vedolizumab in combined immune checkpoint therapy-induced infliximab-refractory colitis in a patient with metastatic melanoma: A case report

BACKGROUND

Dual checkpoint inhibition improves response rates in treatment naïve patients with metastatic melanoma compared to monotherapy. However, it confers a higher rate of toxicity, including immune-related colitis. Steroids may not resolve symptoms in all cases. The use of vedolizumab, a humanized monoclonal antibody against α4β7 integrin has proven effective in cases refractory to standard treatment.

CASE SUMMARY

We report the case of a 27-year-old female with Stage IVd metastatic melanoma treated with ipilimumab and nivolumab. She developed severe colitis refractory to methylprednisolone, infliximab and mycophenolate mofetil but responded to vedolizumab.

CONCLUSION

This case report supports vedolizumab use in severe immune related colitis refractory to standard immunosuppression.

[Clinical Diagnosis and Treatment of Immune-related Adverse Events in Digestive System Related to Immune Checkpoint Inhibitors]

恶性肿瘤的免疫治疗是当前肿瘤研究和治疗领域的热点，免疫检查点分子程序性死亡受体-1（programmed cell death receptor-1, PD-1）和细胞毒性T淋巴细胞相关抗原4（cytotoxic T lymphocyte-associated antigen 4, CTLA-4）相关信号通路的激活可以抑制T淋巴细胞活化，肿瘤细胞通过激活该信号通路实现免疫逃逸。免疫检查点抑制剂（immuno-checkpoint inhibitors, ICIs）通过抑制该信号通路，活化T淋巴细胞发挥机体对肿瘤细胞的清除。因此，ICIs的相关毒性包括免疫相关的不良事件（immune-related adverse effects, irAEs）。消化系统如胃肠道、肝脏作为人体重要的消化吸收器官、代谢解毒器官，同时也是重要的免疫相关器官，是irAEs的常见受累系统。本文将分别对ICIs的肝脏、胃肠道不良反应的发生率、临床表现、诊断和处理分别进行阐述。

The Risk of Diarrhea and Colitis in Patients With Advanced Melanoma Undergoing Immune Checkpoint Inhibitor Therapy: A Systematic Review and Meta-Analysis

Checkpoint inhibitors are a first-line therapy for advanced melanoma, though their use is limited by diarrhea and colitis. The aim of our study was to determine the risk of these toxicities associated with immunotherapy in advanced melanoma. Electronic databases were searched through June 2017 for prospective studies reporting the risk of diarrhea and colitis in advanced melanoma treated with anti-programmed death-1 (PD-1) or anti-cytotoxic T-lymphocyte antigen-4 (CTLA-4) inhibitors. Standardized definitions assessed the grade of diarrhea and colitis. Pooled incidence and weighted relative risk estimates with 95% confidence intervals (CI) were estimated using random effects model. Eighteen studies were included: 6 studies (1537 patients) with PD-1 inhibitors and 15 studies (3116 patients) with CTLA-4 inhibitors. The incidence of all-grade diarrhea was 13.7% (95% CI, 10.1%-17.2%) for anti-PD-1 and 35.4% (95% CI, 30.4%-40.5%) for anti-CTLA-4. The incidence of all-grade colitis was 1.6% (95% CI, 0.7%-2.4%) for anti-PD-1, and 8.8% (95% CI, 6.1%-11.5%) for anti-CTLA-4. When PD-1 inhibitors were compared directly with CTLA-4 inhibitors, the relative risk of all-grade diarrhea was 0.58 (95% CI, 0.43-0.77), and the relative risk of all-grade colitis was 0.16 (95% CI, 0.05-0.51). The rate of therapy discontinuation was numerically higher for anti-CTLA-4 therapy compared with anti-PD-1 therapy. Finally, 2 studies compared combination immunotherapy with anti-CTLA-4 therapy alone. The relative risk of developing all-grade diarrhea and colitis with combination therapy was 1.31 (95% CI, 1.09-1.57) and 1.21 (95% CI, 0.73-1.99), respectively. Diarrhea and colitis are frequent toxicities associated with checkpoint inhibitors, and seem to be most common with CTLA-4 inhibitors.

Immune checkpoint inhibitor-induced diarrhea/colitis: Endoscopic and pathologic findings

The indications of immune checkpoint inhibitors (ICPIs) for cancer treatment have rapidly expanded, and their use is increasing in clinical settings worldwide. Despite the considerable clinical benefits of ICPIs, frequent immune-related adverse events (irAEs) have become nonnegligible concerns. Among irAEs, ICPI-induced colitis/diarrhea is frequent and recognized not only by oncologists but also by gastroenterologists or endoscopists. The endoscopic findings show similarity to those of inflammatory bowel disease to a certain extent, particularly ulcerative colitis, but do not seem to be identical. The pathological findings of ICPI-induced colitis may vary among drug classes. They show acute or chronic inflammation, but it may depend on the time of colitis suggested by colonoscopy, including biopsy or treatment intervention. In the case of chronic inflammation determined by biopsy, the endoscopy findings may overlap with those of inflammatory bowel disease. Here, we provide a comprehensive review of ICPI-induced colitis based on clinical, endoscopic and pathologic findings.

Acute and Long-term Adverse Events Associated With Checkpoint Blockade

OBJECTIVE

To provide an overview of the spectrum of immune-related adverse events associated with immune checkpoint therapy, including presentation, evaluation, management, and nursing considerations.

DATA SOURCES

Peer-reviewed articles, published literature, national guidelines, Internet.

CONCLUSION

Immune checkpoint inhibitor therapies are have become a therapeutic treatment options for many cancers. These therapies promote activity of a patient's adaptive immune system to eradicate cancer. The agents are associated with a unique side-effect profile called Immune-related adverse events. Most of these are low severity. However, if they become more severe, they can be life-threatening or result in permanent organ dysfunction. The key to optimizing therapies is collaborative monitoring, evaluation, documentation, management, communication.

IMPLICATIONS FOR NURSING PRACTICE

Oncology nurses are the front line of patient care. Nurses must have a thorough understanding of the mechanism of action, potential immune-related adverse events, clinical implications, and management strategies. They are responsible for educating patients about immune checkpoint therapies and the potential side effects that may develop, triage management strategies, and coordination of care.

Immuno-oncology for surgeons

Cancer has traditionally been treated with surgery, cytotoxic chemotherapy and/or radiotherapy. The focus of treatment has been the mutated neoplastic cell. Critical advances in genomic and molecular techniques herald the potential for personalized treatments. Incremental breakthroughs in immunology have translated to a step-change in care by providing a mechanistic understanding of the immune system and how it may be mobilized to target cancer cells. As a result, clinical trials of immune-modifying agents have increased at an exponential rate and are revolutionizing cancer care. It is increasingly likely that the surgical oncologist will find themself caring for patients who have had immuno-oncology therapies as part of their neoadjuvant or adjuvant treatment. This review provides an update on immuno-oncology for the surgeon, covering the mechanisms of action of the agents in use. Emerging and surgically relevant toxicities are discussed, and available data on combining and sequencing cancer surgery with immuno-oncology treatments are summarized.

Fecal Microbial Transplantation for Diseases Beyond Recurrent Clostridium Difficile Infection

As microbiome research has moved from associative to mechanistic studies, the activities of specific microbes and their products have been investigated in the development of inflammatory bowel diseases, cancer, metabolic syndrome, and neuropsychiatric disorders. Findings from microbiome research have already been applied to the clinic, such as in fecal microbiota transplantation for treatment of recurrent Clostridium difficile infection. We review the evidence for associations between alterations in the intestinal microbiome and gastrointestinal diseases and findings from clinical trials of fecal microbiota transplantation. We discuss opportunities for treatment of other diseases with fecal microbiota transplantation, based on findings from small clinical and preclinical studies.

Oligomeric Enteral Nutrition in Undernutrition, due to Oncology Treatment-Related Diarrhea. Systematic Review and Proposal of An Algorithm of Action

Oncology treatment-related diarrhea and malnutrition appear together in oncological patients because of the disease itself, or the treatments that are administered for it. Therefore it is essential to carry out a nutritional treatment. Enteral nutrition formulas, containing peptides and medium chain triglycerides, can facilitate absorption in cases of malabsorption. There are few references to the use of enteral nutrition in the clinical society guidelines of patient management with oncology treatment-related diarrhea (OTRD). A bibliographic review of the studies with oligomeric enteral nutrition in OTRD found only nine studies with chemotherapy (all with the same oligomeric formula in which oral mucositis improves, while the rest of the outcomes show different results), and eight studies with radiotherapy (with different products and very heterogeneous results). We hereby present our action algorithm to supplement the diet of OTRD patients with an oligomeric enteral nutrition formula. The first step is the nutritional assessment, followed by the assessment of the functional capacity of the patient’s intestine. With these two aspects evaluated, the therapeutic possibilities available vary in degrees of complexity: These will range from the usual dietary recommendations, to supplementation with oral oligomeric enteral nutrition, along with complete enteral nutrition with oligomeric formula, and up to potentially total parenteral nutrition.

A case of checkpoint inhibitor-induced celiac disease

BACKGROUND

Immune checkpoint inhibitors (ICIs) have now become standard of care treatment for many malignancies. ICIs are associated with unique immune mediated adverse events (irAEs) due to dysregulation of immune activation. As treatment with ICIs is becoming more common, rare irAEs are also being recognized. Here we report a case of ICI-induced celiac disease.

CASE

A 74-year-old Caucasian female with metastatic renal carcinoma received second line nivolumab (anti-PD1 antibody) after initial disease progression on sunitinib. Ipilimumab was added after she failed to respond to six cycles of nivolumab monotherapy. One week after her first cycle of combination treatment, she presented with nausea, vomiting, grade 1 diarrhea, and weight loss. She underwent endoscopy, which showed bile stasis in the stomach, normal appearing stomach mucosa, and nonbleeding erythematous mucosa in the duodenal bulb. Stomach biopsy showed moderate active chronic gastritis. Duodenal biopsy showed moderate chronic active duodenitis with focal neutrophilic cryptitis, mucosal erosions, villous atrophy, mildly increased intraepithelial lymphocytes, and moderate chronic inflammation in the lamina propria pathognomonic of celiac disease. Symptoms improved with gluten-free diet, twice-daily omeprazole and anti-emetics and she was able to continue on treatment.

CONCLUSIONS

There has been only one published case reporting ICI-induced celiac disease. Our case report highlights a rare irAE (celiac disease) associated with ICI treatment. It is unclear whether the patient had previously undiagnosed celiac disease or whether ICIs triggered her enteritis. Our patient was able to continue treatment with ICIs with dietary modifications, suggesting correct diagnosis is critical for optimal patient outcome.

New oncologic emergencies: What is there to know about inmunotherapy and its potential side effects?

Over the last decade anticancer treatment has experienced encouraging changes. One of the latest developments is immunotherapy, which is increasingly becoming a mainstay for the treatment of these malignancies. Unlike conventional chemotherapy, immunotherapy enhances anti-tumor immune response by blocking inhibitory immune checkpoints, and allowing our own immune system to fight against the tumor cells, arising as a new and innovative mechanism of action. Therefore, although well tolerated, these drugs have a unique side effect profile and are known to cause immune-related adverse events (irAEs). Adverse effects of immunotherapy are most commonly observed in the skin, gastrointestinal tract, liver, lung and endocrine systems. Less common toxicities may include neurological, haematological, cardiac, ocular or rheumatologic involvement. As far as we know, cancer patients are frequently seen in the Emergency Department due to treatment related toxicities, thus there is an increasing necessity to learn about this particular side effect profile given that they entail a different and unique management than that of classic chemotherapy drugs.

A Review of Immune-Mediated Adverse Events in Melanoma

The use of checkpoint inhibitor-based immunotherapy has transformed the treatment landscape for melanoma as well as many other cancer types. With the ability to potentiate tumor-specific immune responses, these agents can result in durable tumor control. However, this activation of the immune system can lead to a unique constellation of side effects, distinct from other cancer therapies, collectively termed immune-mediated adverse events (irAEs). This review will focus on irAEs and guidelines for management related to the most clinically relevant checkpoint inhibitors, those that target programmed death receptor-1 (PD-1) and cytotoxic T lymphocyte antigen-4 (CTLA-4).

Delayed immune-related events (DIRE) after discontinuation of immunotherapy: diagnostic hazard of autoimmunity at a distance

BACKGROUND

The risk of delayed autoimmunity occurring months or years after discontinuation of immunotherapy is frequently asserted in the literature. However, specific cases were rarely described until 2018, when a wave of reports surfaced. With expanding I-O indications in the adjuvant/neoadjuvant curative setting, growing numbers of patients will receive limited courses of immunotherapy before entering routine surveillance. In this context, under-recognition of DIRE could pose a growing clinical hazard.

METHODS

The aim of this study was to characterize DIRE through identification of existing reports of delayed post-treatment irAE in cancer patients treated with immunotherapy. We performed a PubMed literature review from 2008 through 2018 to determine the median data safety reporting window from existing I-O clinical trials, which we then applied to define the DIRE cutoff, and collated all qualifying reports over the same time span. DIRE was defined as new immune-related adverse events (irAE) manifesting ≥90 days after discontinuation of immunotherapy.

RESULTS

Median duration of I-O clinical trials data safety reporting was 90 days (82% ≤ 90 days). DIRE cutoff was thus set as ≥90 days post-immunotherapy. We identified 23 qualifying cases; 21 by literature review and 2 from our institution. Median off-treatment interval to DIRE was 6 months (range: 3 to 28). Median cumulative immunotherapy exposure was 4 doses (range: 3 to 42). Involvement included endocrine, neurologic, GI, pulmonary, cardiac, rheumatologic and dermatologic irAE.

CONCLUSIONS

As immunotherapy indications expand into the curative setting, often with brief exposure and potentially sequenced with multimodality treatments, it will be necessary to recognize an emerging diagnostic complex, which we have termed delayed immune-related events (DIRE). Clinical vigilance has the potential to reduce morbidity from diagnostic delay, as irAE are generally manageable with prompt initiation of treatment - or from misdiagnosis - as misattribution can lead to unnecessary or harmful interventions as we describe. DIRE should therefore figure prominently in the differential diagnosis of patients presenting with illnesses of unclear etiology, irrespective of intervening treatments or interval post-immunotherapy, both of which can confound diagnosis. Increased recognition will rest on delineation of DIRE as a clinical diagnostic entity.

Immune Checkpoint Inhibitor Toxicities

Immune checkpoint inhibitors are molecules that increase the endogenous immune response against tumors. They have revolutionized the field of oncology. Since their initial approval for the treatment of advanced melanoma, their use has expanded to the treatment of several other advanced cancers. Unfortunately, immune checkpoint inhibitors have also been associated with the emergence of a new subset of autoimmune-like toxicities, known as immune-related adverse events. These toxicities differ depending on the agent, malignancy, and individual susceptibilities. Although the skin and colon are most commonly involved, any organ may be affected, including the liver, lungs, kidneys, and heart. Most of these toxicities are diagnosed by excluding other secondary infectious or inflammatory causes. Corticosteroids are commonly used for treatment of moderate and severe immune-related adverse events, although additional immunosuppressive therapy may occasionally be required. The occurrence of immune-related toxicities may require discontinuation of immunotherapy, depending on the specific toxicity and its severity. In this article, we provide a focused review to familiarize practicing clinicians with this important topic given that the use of immune checkpoint inhibitors continues to increase.

Mucosal Injury during Anti-Cancer Treatment: From Pathobiology to Bedside

Mucositis is one of the most common debilitating side effects related to chemotherapy (CT), radiation therapy (RT), targeted agents and immunotherapy. It is a complex process potentially involving any portion of the gastrointestinal tract and injuring the mucosa, leading to inflammatory or ulcerative lesions. Mechanisms and clinical presentation can differ according both to the anatomic site involved (oral or gastrointestinal) and the treatment received. Understanding the pathophysiology and management of mucosal injury as a secondary effect of anti-cancer treatment is an important area of clinical research. Prophylaxis, early diagnosis, and adequate management of complications are essential to increase therapeutic success and, thus, improve the survival outcomes of cancer patients. This review focuses on the pathobiology and management guidelines for mucositis, a secondary effect of old and new anti-cancer treatments, highlighting recent advances in prevention and discussing future research options.

Immune-Related Adverse Events: A Case-Based Approach

Immunotherapy has heralded the advent of a new era in oncology. Immune checkpoint inhibitors (ICIs) enhance anti-tumor immunity, thereby reinvigorating a patient's immune system to fight cancer. While therapy with this class of agents has resulted in improved clinical outcomes for patients with multiple tumor types, a broad spectrum of immune-related adverse events (irAEs) may affect any organ system, with variable clinical presentations. Prompt recognition and management of irAEs are associated with improved irAE outcomes, and represents an important new clinical challenge for practicing oncologists. Herein, we provide a comprehensive case-based review of the most common and clinically-important irAEs, focussing on epidemiology, clinical manifestations, and management. We also examine future strategies that may provide meaningful insights into the prevention and management of irAEs.

Systematic review and case series: flexible sigmoidoscopy identifies most cases of checkpoint inhibitor-induced colitis

BACKGROUND

Immune checkpoint inhibitors are used in the treatment of multiple advanced stage cancers but can induce immune-mediated colitis necessitating treatment with immunosuppressive medications. Diagnostic colonoscopy is often performed but requires bowel preparation and may delay diagnosis and treatment. Sigmoidoscopy can be performed rapidly without oral bowel preparation or sedation.

AIMS

Characterize the colonic distribution of immune-mediated colitis to determine the most efficient endoscopic approach.

METHODS

A systematic review of checkpoint inhibitor-induced colitis case reports and series was conducted in both PubMed and Embase through 3 January 2017. A single centre retrospective chart review of patients who underwent endoscopic evaluation for diarrhoea after treatment with a checkpoint inhibitor (ipilimumab, nivolumab or pembrolizumab) between 1 January 2011 and 3 January 2017 was performed. Clinical, endoscopic and histologic data were collected.

RESULTS

A detailed systematic review resulted in 61 studies, in which 226 cases of colitis were diagnosed by lower endoscopy (125 colonoscopy, 101 sigmoidoscopy). Only four patients had isolated findings proximal to the left colon. In our centre, 31 patients had histologic features of checkpoint inhibitor-induced colitis, for which 29 patients had complete data. The left colon was involved in all cases. Sigmoidoscopy would be sufficient to diagnose >98% of reported cases of checkpoint inhibitor-mediated colitis diagnosed by lower endoscopy.

CONCLUSIONS

Moderate to severe checkpoint inhibitor-induced colitis involves the left colon in the majority of cases (>98%). Sigmoidoscopy should be the initial endoscopic procedure in the evaluation of this condition.

Incidence of pancreatitis with the use of immune checkpoint inhibitors (ICI) in advanced cancers: A systematic review and meta-analysis

BACKGROUND

Systemic immune side effects including pancreatitis have been reported with the use of Immune Checkpoint Inhibitors (ICI) (CTLA-4, PD-1 and PDL-1). However, the true incidence, risk, causes (tumor or drug specific) of pancreatitis and relation to other immune side effects, especially diabetes mellitus (DM) are unknown.

METHODS

We performed a systematic review and meta-analysis of all clinical trials using ICI for the incidence of any grade lipase elevation, pancreatitis or DM.

RESULTS

The incidence of asymptomatic lipase elevation after ICI use is 2.7% (211/7702) and grade 2 pancreatitis is 1.9% (150/7702). No pancreatitis related mortality has been reported in these clinical trials. Patients treated with CTLA-4 inhibitors have increased incidence of pancreatitis when compared to patients treated with PD1 inhibitors 3.98% (95% CI: 2.92 to 5.05) vs 0.94% (95% CI: 0.48 to 1.40); P value < 0.05. Patients treated with ICI for melanoma have increased incidence of pancreatitis when compared to non-melanoma cancers. We also noted an additive increase in incidence of pancreatitis with combination of CTLA4 and PD-1 inhibitors (10.60; 95% CI: 7.89 to 13.32) compared with either CTLA-4 or PD-1 inhibitors alone.

CONCLUSIONS

Our study provides precise data for the incidence of pancreatitis among patients using ICI based on tumor types and ICI regimens. ICI use for solid tumors is associated with increased incidence of all grades of lipase elevation and pancreatitis, especially for CTLA-4 agents and ICI combination. Although it does not appear to be associated with mortality, ICI related pancreatitis should be recognized early for appropriate treatment and to potentially reduce long term complications.

Upper gastrointestinal symptoms and associated endoscopic and histological features in patients receiving immune checkpoint inhibitors

Background: Immune checkpoint inhibitors (ICIs) have demonstrated effectiveness in treating many malignancies. Gastrointestinal (GI) adverse events are commonly reported; however, few reports describe upper GI tract toxic effects. We aimed to describe clinical features of upper GI injury related to ICI. Methods: We studied consecutive patients who received ICIs between April 2011 and March 2018 and developed upper GI symptoms requiring esophagogastroduodenoscopy (EGD). Results: Sixty patients developed upper GI symptoms between ICI initiation and 6 months after the last infusion. Among patients who had both EGD and colonoscopy (n = 38), 21 had endoscopic evidence of inflammation involving both the upper and lower GI tract. Overall, histological signs of inflammation of the stomach were evident in 83% of patients, but inflammation of the duodenum in 38%. Total of 42 patients had other risk factors of gastritis, i.e., chemotherapy, radiotherapy, and non-steroidal anti-inflammatory drugs. Only isolated gastric inflammation was seen on endoscopy in patients without these risk factors. The rates of ulceration were similar in the cohorts with and without other risk factors for gastritis. Isolated upper GI inflammation was related to anti-PD-1/L1 in 47% of patients. Immunosuppressive therapy in our cohort with upper GI toxicity consisted of steroids (42%) and infliximab or vedolizumab (23%). Most isolated upper GI symptoms were treated with proton pump inhibitors (65%) or H₂ blockers (35%). Conclusion: We observed a correlation between ICI use and onset of upper GI inflammation even when other risk factors were excluded. Gastric involvement was evident more often than duodenal involvement on endoscopic and histological level.

Case report: reinitiating pembrolizumab treatment after small bowel perforation

BACKGROUND

Immune checkpoint inhibitors (ICIs) have emerged as paradigm shifting treatment options for a number of cancers. Six antibodies targeting the immune checkpoint proteins programmed cell death 1 (PD-1), programmed cell death 1 ligand 1 (PD-L1) or cytotoxic T-lymphocyte associated protein 4 (CTLA4) have been approved. In some cases, response rates have been impressive, but not uniformly so and not consistently; similarly, toxicity to this class of therapeutic is often unpredictable and can be life threatening. Predicting treatment response and toxicity are two main obstacles to truly individualize treatment with ICIs. One of the most severe and life-threatening adverse events is colitis induced colonic perforation, estimated to occur in 1.0 to 1.5% of patients treated with ICIs. An important question to address is, under what circumstances is it appropriate to reinitiate ICI treatment post-bowel perforation?

CASE PRESENTATION

The patient is a 62-year-old woman, who presented with stage IV lung cancer. Immunohistochemical staining indicated that 80% of the patient's tumor cells expressed PD-L1. The patient was started on a three-week cycle of pembrolizumab. Subsequent reducing in tumor burden was observed within ten weeks. Initially, pembrolizumab was tolerated fairly well, with the exception of immunotherapy related hypothyroidism. However, the patient experienced a second, more serious immune-related adverse event (irAE), in the form of enteritis, which led to small bowel perforation and necessitated exploratory laparotomy. The concerning part of the small bowel was resected, and a primary anastomosis was created. Based on the pathological and surgical findings, the patient was diagnosed with pembrolizumab-associated small bowel perforation. The patient recovered well from surgery and, considering the patient's remarkable response to treatment, a collective decision was made to reinitiate pembrolizumab on post-operative day twenty-eight. The patient is continuing her immunotherapy with ongoing partial response and is able to continue her full-time job.

CONCLUSIONS

This case report highlights the challenges of identifying patients likely to respond to ICIs and those that are likely to experience irAEs and it discusses the impressive work that has been done to start to address these challenges. Lastly, the topic of reinitiating pembrolizumab treatment even after colonic perforation is discussed.

Adverse Event Profiles of Anti-CTLA-4 and Anti-PD-1 Monoclonal Antibodies Alone or in Combination: Analysis of Spontaneous Reports Submitted to FAERS

BACKGROUND AND OBJECTIVE

Immune checkpoint inhibitors (ICIs)-cytotoxic T-lymphocyte antigen-4 (CTLA-4) and programmed death receptor-1 (PD-1) monoclonal antibodies (mAbs)-either as single agents or in combination have become the standard of care for an increasing number of indications. Understanding both the ICI-associated adverse events (AEs) and the possible rank-order of these drugs in terms of susceptibility is essential if we are to improve the curative effect and reduce toxicity.

METHODS

We detected signals of the AEs of ICIs by data mining using the US Food and Drug Administration (FDA) AEs Reporting System (FAERS) database. The definition relied on the preferred terms (PTs) and the standardized MedDRA Queries (SMQs) provided by the Medical Dictionary for Regulatory Activities (MedDRA). Disproportionality analysis was performed by calculating the reporting odds ratios (ROR) with 95% confidence intervals (CIs).

RESULTS

Adverse effects of CTLA-4 and PD-1 mAbs were most commonly observed in the skin, gastrointestinal tract, endocrine systems, liver, and lung, and they included rash, diarrhea, colitis, and thyroid dysfunction. Thyroid dysfunction, type 1 diabetes mellitus, and pneumonitis were more closely associated with the use of anti-PD-1, whereas colitis, diarrhea, hypophysitis, and adrenal insufficiency were more closely associated with anti-CTLA-4; rash and hepatitis occurred similarly in both. Disproportionality signals for less common AEs in other organ systems, including the renal, neurological, cardiac, ocular, musculoskeletal, and hematologic systems, were also detected. Nivolumab and pembrolizumab have very similar safety profiles, but the signal strength of AEs increased when combined with ipilimumab.

CONCLUSIONS

The results of this study are in agreement with clinical observations, suggesting the usefulness of pharmacovigilance in "real-world" safety monitoring.

Regulatory T cell adaptation in the intestine and skin

The intestine and skin are distinct microenvironments with unique physiological functions and are continually exposed to diverse environmental challenges. Host adaptation at these sites is an active process that involves interaction between immune cells and tissue cells. Regulatory T cells (T_reg cells) play a pivotal role in enforcing homeostasis at barrier surfaces, illustrated by the development of intestinal and skin inflammation in diseases caused by primary deficiency in T_reg cells. T_reg cells at barrier sites are phenotypically distinct from their lymphoid-organ counterparts, and these 'tissue' signatures often reflect their tissue-adapted function. We discuss current understanding of T_reg cell adaptation in the intestine and skin, including unique phenotypes, functions and metabolic demands, and how increased knowledge of T_reg cells at barrier sites might guide precision medicine therapies.

Management of Immunotherapy-Related Toxicities, Version 1.2019, NCCN Clinical Practice Guidelines in Oncology

The aim of the NCCN Guidelines for Management of Immunotherapy-Related Toxicities is to provide guidance on the management of immune-related adverse events resulting from cancer immunotherapy. The NCCN Management of Immunotherapy-Related Toxicities Panel is an interdisciplinary group of representatives from NCCN Member Institutions and ASCO, consisting of medical and hematologic oncologists with expertise in a wide array of disease sites, and experts from the fields of dermatology, gastroenterology, neuro-oncology, nephrology, emergency medicine, cardiology, oncology nursing, and patient advocacy. Several panel representatives are members of the Society for Immunotherapy of Cancer (SITC). The initial version of the NCCN Guidelines was designed in general alignment with recommendations published by ASCO and SITC. The content featured in this issue is an excerpt of the recommendations for managing toxicity related to immune checkpoint blockade and a review of existing evidence. For the full version of the NCCN Guidelines, including recommendations for managing toxicities related to chimeric antigen receptor T-cell therapy, visitNCCN.org.

Immune checkpoint inhibitor-induced colitis: A comprehensive review

Immune checkpoint inhibitors (ICIs) are monoclonal antibodies that target down-regulators of the anti-cancer immune response: Cytotoxic T-lymphocyte antigen-4, programmed cell death protein-1, and its ligand programmed death-ligand 1. ICIs have revolutionized the treatment of a variety of malignancies. However, many immune-related adverse events have also been described which mainly occurs as the immune system becomes less suppressed, affecting various organs including the gastrointestinal tract and causing diarrhea and colitis. The incidence of immune-mediated colitis (IMC) ranges from 1%-25% depending on the type of ICI and if used in combination. Endoscopically and histologically there is a significant overlap between IMC and inflammatory bowel disease, however more neutrophilic inflammation without chronic inflammation is usually present in IMC. Corticosteroids are recommended for grade 2 or more severe colitis while holding the immunotherapy. About one third to two thirds of patients are steroid refractory and benefit from infliximab. Recently vedolizumab has been found to be efficacious in steroid and infliximab refractory cases. While in grade 4 colitis, the immunotherapy is permanently discontinued, the decision is controversial in grade 3 colitis.

Can Immune Checkpoint Inhibitors Induce Microscopic Colitis or a Brand New Entity?

BACKGROUND

Microscopic colitis (MC) has been described as 1 pattern of injury in immune checkpoint inhibitor (ICPI)-induced colitis. The main objective of this study was to characterize ICPI-induced MC by exploring the differences in risk factors, colitis treatments, endoscopic features, and clinical outcomes between cancer and noncancer patients with MC with and without exposure to ICPIs.

METHODS

A retrospective chart review was conducted among patients diagnosed with MC from our institutional pathology database from January 2012 to January 2018. Patients were categorized into MC in cancer patients with or without ICPI exposure and in noncancer patients. Risk factors (use of tobacco and certain medications), colitis treatments (antidiarrheals and immunosuppressants), endoscopic features (with or without mucosal abnormality), and clinical outcomes (diarrhea recurrence, hospitalization, mortality) were collected and compared among the 3 groups.

RESULTS

Of the 65 eligible patients with MC, 15 cancer patients had exposure to ICPI, 39 cancer patients had no exposure to ICPI, and 11 had no cancer diagnosis. Among the risk factors, proton pump inhibitor was more frequently used in the ICPI-induced MC cohort (P = 0.040). Furthermore, in this population, mucosal abnormality was the most common endoscopic feature compared with normal findings in the non-ICPI-induced MC groups (P = 0.106). Patients with ICPI-induced MC required more treatments with oral and intravenous steroids and nonsteroidal immunosuppressive agents (all P < 0.001) and had a higher rate of hospitalization (P < 0.001).

CONCLUSION

This study suggests that despite some similarities between MC with and without exposure to ICPIs, ICPI-induced MC has a more aggressive disease course that requires more potent immunosuppressive treatment regimens and greater need for hospitalization. 10.1093/ibd/izy240_video1izy240.video15828223597001.

Practical guidance for the management of inflammatory bowel disease in patients with cancer. Which treatment?

Clinicians involved in the treatment of inflammatory bowel disease (IBD) increasingly come across patients with current or previous history of malignancies. With increasing and earlier use of immunosuppression and biologics in IBD patients, the question arises whether these treatments further increase the risk of new or recurrent cancers. A number of population-based observational studies have now reported the odds of development of new or recurrent cancers with thiopurines and antitumour necrosis factors (anti-TNFs). These data combined with data arising from treatment registries from other immune disorders such as rheumatoid arthritis are providing evidence of relative risks and safety profiles of these agents in the setting of active or prior cancer. Data from transplant literature give an indication for providing a drug-holiday period in patients with treated cancers. The risks of the treatment should be considered alongside the risk associated with withholding these effective treatments in patients with active IBD. In this review, we aim to summarize the current evidence in this area and provide a practical guidance.

Adverse effects and radiological manifestations of new immunotherapy agents

Immunotherapy has had increasing use in Medical Oncology for a diverse range of primary malignancies. There are various types of immunotherapy which are grouped based on mechanism of action. In recent decades, the immune checkpoint inhibitors (ICI) immunotherapies have been at the forefront of Medical Oncology, sparked by very encouraging results. Some patients with metastatic cancer who were previously deemed palliative were seeing durable response rates and significant increased survival with ICIs. The mechanism of action of ICIs vary wildly compared to the conventional, cytotoxic chemotherapy, upon which traditional radiology response criteria were based and validated upon. Novel responses such as pseudo progression, disease response in the context of new metastases and prolonged stable disease were observed and correlated with improved patient survival with ICI. New radiology response criteria were proposed to better capture disease response to ICI; however, the criteria have been applied heterogeneously and there is continued work in this sector. In addition to the novel responses, ICIs have been linked to numerous, diverse immune-related adverse events (irAE) affecting multiple systems. A large majority of these are mild, but some irAEs are life threatening. Only some of the irAEs have radiological manifestations. It is important that the reporting radiologist recognises potential irAE so clinical teams can be alerted, ICI treatment paused or cessated and steroid treatment initiated. This review will discuss the evolution of the radiology response criteria in ICI and the varied radiological appearances of irAE.

Tipping the balance: inhibitory checkpoints in intestinal homeostasis

The small intestinal and colonic lamina propria are populated with forkhead box P3 (FOXP3)⁺CD4⁺ regulatory T cells (Tregs) and interleukin-10-producing T cells that orchestrate intestinal tolerance to harmless microbial and food antigens. Expression of co-inhibitory receptors such as CTLA-4 and PD-1 serve as checkpoints to these cells controlling their T-cell receptor (TCR)-mediated and CD28-mediated activation and modulating the phenotype of neighboring antigen presenting cells. Recent discoveries on the diversity of co-inhibitory receptors and their selective cellular expression has shed new light on their tissue-dependent function. In this review, we provide an overview of the co-inhibitory pathways and checkpoints of Treg and effector T cells and their mechanisms of action in intestinal homeostasis. Better understanding of these inhibitory checkpoints is desired as their blockade harbors clinical potential for the treatment of cancer and their stimulation may offer new opportunities to treat chronic intestinal inflammation such as inflammatory bowel disease.

Management of Gastrointestinal Toxicity from Immune Checkpoint Inhibitor

Immune checkpoint inhibitors have shown anti-tumour activity in cancers such as melanoma, renal cell carcinoma, non-small-cell lung cancer, urothelial carcinoma, colorectal cancer, and Hodgkin's lymphoma. Though immune checkpoint inhibitors have revolutionized the treatment and prognosis of some advanced malignancies, they are also associated with a significant risk of immune-related adverse events. These adverse events can occur in any organ system, but gastrointestinal side effects are among the most commonly reported, with manifestations ranging from mild diarrhoea to severe colitis, sharing some features with inflammatory bowel disease. Anticipating a greater use of these drugs in the future, gastroenterologists should expect to be increasingly faced with gastrointestinal immune-related adverse events. Knowledge of these toxicities, as well as effective management algorithms, is essential to enable early diagnosis and treatment, decreasing morbidity and mortality. We reviewed the currently available literature on gastrointestinal toxicity induced by immune checkpoint inhibitors, namely the clinical features, diagnosis, and management.

Endoscopic evaluation of immunotherapy-induced gastrointestinal toxicity

Immunotherapy is any treatment aimed at boosting or enhancing the immune system. It includes a wide range of options, from vaccines to treatment for conditions such as allergy and cancer. In the case of cancer, unlike other available treatments, immunotherapy is not aimed at destroying the tumor cells but at stimulating the patient’s immune system so that it attacks the tumor. In cancer, immunotherapy provides a series of advantages. Nevertheless, immunotherapy administered for treatment of cancer is associated with immune-mediated enterocolitis. Colitis mediated by monoclonal anti-cytotoxic T lymphocyte–associated antigen 4 and to programmed cell death protein 1 and its ligand PDL1 shares characteristics with chronic inflammatory bowel disease (IBD), and similar findings have been reported for both the endoscopy images and the segment involved. The most frequent lesions on endoscopy are ulcer and erythema, and the most frequently affected site is the sigmoid colon. A segmental pattern has been reported to be slightly more frequent than a continuous pattern. In addition, upper gastrointestinal lesions have been reported in up to half of patients, with the most frequent findings being gastritis and erosive duodenitis. As is the case in IBD, systemic corticosteroids and immunosuppressive treatment (anti-TNF agents) are the approaches used in patients with a more unfavorable progression. Immunotherapy must be suspended completely in some cases.

Effectiveness and safety of PD-1/PD-L1 or CTLA4 inhibitors combined with chemotherapy as a first-line treatment for lung cancer: A meta-analysis

Background

Immune checkpoint inhibitors (ICIs) combined with chemotherapy have been applied as a first-line treatment for lung cancer, but consistent beneficial results have not been documented. Therefore, our meta-analysis aimed to evaluate the effectiveness and safety of combination therapy to promote its application.

Methods

We searched electronic databases for studies that estimated the safety and efficacy of combined therapy. The objective response rate (ORR) and disease control response (DCR) parameters were evaluated with odds ratio (OR) values of the combination arm over the non-combination arm. Hazard ratios (HR) and its 95% confidence intervals (95% CI) were used to calculate progression-free survival (PFS) and overall survival (OS) in the combination and non-combination arms. All treatment-related adverse events (TRAEs) and 3 to 5 TRAEs were expressed as relative risk (RR) values of the combination arm over the non-combination arm.

Results

Ten eligible studies involving 4,887 patients were identified. The pooled ORs for ORR and DCR were 1.85 (95% CI: 1.30-2.63, P<0.01) and 1.14 (95% CI: 0.70-1.86, P<0.01), respectively. The pooled HRs for PFS and OS were 0.67 (95% CI: 0.58-0.79, P<0.001) and 0.76 (95% CI: 0.65-0.88, P<0.001), respectively. In subgroup analysis, ORR and DCR were significantly improved in the programmed cell death-1/L1 (PD-1/L1) blockade for non-small cell lung cancer (NSCLC) group (subgroup A), with a combined OR values of 2.36 (95% CI: 1.79-3.13, P<0.001) and 1.92 (95% CI: 1.10-3.35, P<0.001), respectively. However, no significant benefits were observed in the cytotoxic T lymphocyte antigen-4 (CTLA-4) blockade for small cell lung cancer (SCLC) (subgroup B) and CTLA-4 blockade for NSCLC groups (subgroup C). In addition, a significant improvement in PFS was observed in subgroup A, subgroup B and subgroup C, with pooled HR values of 0.58 (95% CI: 0.52-0.63, P<0.001), 0.86 (95% CI: 0.76-0.97, P<0.05) and 0.83 (95% CI: 0.68-1.00, P<0.05), respectively. Only subgroup A exhibited an OS benefit, with a combined HR value of 0.67 (95% CI: 0.55-0.81, P<0.001). Moreover, as the expression of PD-L1 increased, the PFS and OS benefits were more significantly. Furthermore, patients without central nervous system (CNS) metastasis who were treated with PD-1/L1 inhibitors had a longer OS than patients with CNS metastasis (HR: 0.67, 95% CI: 0.55-0.80, P<0.001). Finally, combined therapy was associated with 3 to 5 TRAEs (RR: 1.26, 95% CI: 1.08-1.47; P<0.01).

Conclusions

Patients treated with immunotherapy and chemotherapy in combination exhibited superior in ORR, DCR, PFS and OS as well as slightly increased TRAE levels compared with those of patients treated with either monotherapy.

Evolution and recurrence of gastrointestinal immune-related adverse events induced by immune checkpoint inhibitors

BACKGROUND

Immune checkpoint inhibitors (ICIs), such as anti-CTLA-4 and anti-PD-1 antibodies, are effective against several malignancies. They are associated with gastrointestinal immune-related adverse events (GI-IrAEs), which may be severe and lead to ICI discontinuation. We assessed the risk of evolution of GI-IrAEs to chronic GI inflammation and the risk of recurrence after a second line of ICI.

PATIENTS AND METHODS

This was a single-centre study. Included patients had a GI-IrAE due to ICIs between September 2010 and July 2017. We assessed the persistence of symptoms, endoscopic and/or histological inflammation, and the risk of recurrent GI-IrAEs after the second line of ICIs.

RESULTS

Eighty patients were included. The median follow-up was 8.4 months (0.36-72.3). The median duration of GI symptoms was 1.5 months (5 days-10.3 months): 1.4 months (7 days-4.9 months) with anti-CTLA-4, 2.0 months (5 days-10.3 months) with anti-PD-1 and 1.0 month (8 days-3.4 months) with combination therapy (log-rank test: p = 0.02). Three and 6 months after the beginning of GI-IrAEs, 22% (95% confidence interval: 14%-33%) and 5.4% (2.0%-14.7%) of patients had persistent symptoms, respectively. After a median of 6 months, 20/27 patients had endoscopic and/or histological inflammation, of whom, seven were symptom free. After the first episode, 6/26 patients relapsed after receiving another course of ICIs. Among these 26, 89% (77%-100%) had no recurrence after 3 months, 71% or 95% if the second line was anti-CTLA-4 or anti-PD-1, respectively.

CONCLUSION

GI-IrAEs seem to be acute or subacute, not chronic. Reintroduction of ICIs is possible in patients who had GI-IrAE.

The current state of the art for biological therapies and new small molecules in inflammatory bowel disease

The emergence of biologic therapies is arguably the greatest therapeutic advance in the care of inflammatory bowel disease (IBD) to date, allowing directed treatments targeted at highly specific molecules shown to play critical roles in disease pathogenesis, with advantages in potency and selectivity. Furthermore, a large number of new biologic and small-molecule therapies in IBD targeting a variety of pathways are at various stages of development that should soon lead to a dramatic expansion in our therapeutic armamentarium. Additionally, since the initial introduction of biologics, there have been substantial advances in our understanding as to how biologics work, the practical realities of their administration, and how to enhance their efficacy and safety in the clinical setting. In this review, we will summarize the current state of the art for biological therapies in IBD, both in terms of agents available and their optimal use, as well as preview future advances in biologics and highly targeted small molecules in the IBD field.

Enterocolitis due to immune checkpoint inhibitors: a systematic review

Immune checkpoint inhibitors targeting cytotoxic T-lymphocyte-associated protein-4 (CTLA-4) and programmed death-1 (PD-1)/ligand are increasingly used to treat several types of cancer. These drugs enhance antitumour T-cell activity and therefore induce immune-related adverse effects (irAE), of which gastrointestinal (GI) irAE are among the most frequent and severe. This systematic literature review summarises the clinical manifestations, management and pathophysiology of GI irAE due to immune checkpoint inhibitors. GI irAE induced by anti-CTLA-4 are frequent, potentially severe and resemble IBD, whereas those induced by PD-1 blockade seem to be less frequent and clinically more diverse. Baseline symbiotic gut microbiota is associated with an enhanced antitumour response to immune checkpoint inhibitors and an increased susceptibility to developing enterocolitis, in patients treated with anti-CTLA-4. These findings open new perspectives for possible manipulation of the gut microbiota in order to better identify responders to immune checkpoint inhibitors and to increase their efficacy and safety.

Immune Checkpoint Inhibitor-Associated Colitis and Hepatitis

Immune checkpoint inhibitors (ICPIs) are monoclonal antibodies that target downregulators of the anti-cancer immune response: cytotoxic T-lymphocyte antigen-4, programmed cell death protein-1, and its ligand PD-L1. ICPIs are now approved for the treatment of a wide array of malignancies, with rates of durable responses in the metastatic setting far exceeding what would be expected from conventional chemotherapy. ICPIs have also been associated with rare but serious immune-related adverse events due to over-activation of the immune system that can affect any organ, including the gastrointestinal tract and liver. As the use of ICPIs in oncology continues to increase, ICPI-associated colitis and hepatitis will be encountered frequently by gastroenterologists and hepatologists. This review will focus on the diagnosis and management of ICPI-associated colitis and hepatitis. We will also compare these ICPI-related toxicities with sporadic inflammatory bowel disease and autoimmune liver disease.

Management of challenging immune-related gastrointestinal adverse events associated with immune checkpoint inhibitors

Immune-related gastrointestinal toxicities (irGI) are well-known adverse events (AEs) with immune checkpoint inhibitors. The aim of this review was to present clinical data from 82 cases to provide information to clinicians who face real-world challenges among their patients with irGI AEs. The findings of this review support the use of the current management guidelines. By analyzing the treatment courses and outcomes of all cases identified, our review recommends that recurrent cases be treated carefully regardless of the grade of diarrhea at the onset of events. Earlier gastroenterology consultation and computed tomography/endoscopy diagnosis are essential, especially when an irGI AE recurs or worsens during steroid tapering. We would also suggest earlier decision to add immunosuppressant agents, particularly for recurrent cases.

Immune-Related Adverse Events in Cancer Patients Treated With Immune Checkpoint Inhibitors

PURPOSE OF REVIEW

With the advent of cancer immunotherapy and immune checkpoint inhibitors, patients with malignancies can now achieve durable remissions for conditions previously described as terminal. However, immune-related adverse events (irAEs) associated with cancer immunotherapy have become an anticipated consequence of enhanced T cell activation. Through an extensive literature review, we assess the most recent clinical and basic research data concerning immune checkpoint blockade and describe the spectrum of associated irAEs as well as their management.

RECENT FINDINGS

Anti-PD-1, anti-PD-L1, and anti-CTLA-4 antibodies are widely used in the management of an array of tumors with incredible clinical remissions. However, irAEs cause significant morbidity and mortality and in some cases, result in withdrawal of cancer therapy and initiation of immunosuppression. While this is an exciting time in oncology, irAEs are a barrier to adequate care and therefore deserve close attention and improved capacity to predict and prevent toxicity. Rheumatologists should be familiar with these topics in the eventuality of patient evaluation and management.

The characteristics of nivolumab-induced colitis: an evaluation of three cases and a literature review

BACKGROUND

The use of immune-checkpoint inhibitors in cancer treatment has become increasingly common, resulting in an increase in the incidence of related side effects. Diarrhoea and colitis have been previously documented as gastrointestinal tract-related side effects of immune-checkpoint inhibitors. Although PD-1/PD-L1 inhibitors produce fewer side effects than CTLA-4 inhibitors, diarrhoea and colitis continue to be reported. However, little is known about the endoscopic features associated with PD-1/PD-L1 inhibitors. In this report, we describe three cases of colitis induced by a PD-1 inhibitor nivolumab. These cases showed endoscopic findings characteristic of ulcerative colitis (UC). Treatment was in accordance with UC therapy, which resulted in beneficial outcomes.

CASE PRESENTATION

Three patients with lung cancer treated with nivolumab presented with diarrhoea with (case 2) or without haematochezia (cases 1 and 3). Treatment with nivolumab was ceased and colonoscopy was performed, revealing endoscopic features similar to those of UC. These patients were diagnosed with nivolumab-induced colitis. Case 1 was treated with mesalazine, whereas cases 2 and 3 were treated with corticosteroids. Subsequently, their symptoms improved.

CONCLUSIONS

Nivolumab-induced colitis exhibited similar characteristics to UC. Treatment was similar to that for UC and was successful.

[Hepatic and digestive adverse events of immune checkpoint inhibitors (anti-CTLA-4 and, anti-PD-1/PD-L1): A clinico-pathological review]

Immune checkpoint inhibitors (anti-CTLA-4 and anti-PD-1/PD-L1) have recently revolutionized anti-cancer therapy and are nowadays used in different metastatic cancers. These treatments may induce immune-related adverse events which frequently involve the digestive tract and, to a less extent the liver. The tissular injuries, which are still poorly characterized from a morphological and physiopathological point of view, may lead on one side to the interruption of a life-saving treatment and on the other side to the development of severe complications, if not death. Therefore, it is crucial to diagnose as early as possible and treat these digestive and hepatic adverse effects in an optimal way. This article aims to describe the clinical and pathological presentations of digestive and hepatic adverse events induced by these immunotherapies.

Differential diagnosis of inflammatory bowel disease: imitations and complications

Inflammatory bowel disease (IBD) is characterised by episodes of relapse and periods of remission. However, the clinical features, such as abdominal pain, diarrhoea, and rectal bleeding, are not specific. Therefore, the differential diagnosis can include a broad spectrum of inflammatory or infectious diseases that mimic IBD, as well as others that might complicate existing IBD. In this Review, we provide an overview of ileocolitis of diverse causes that are relevant in the differential diagnosis of IBD. We highlight the importance of accurate patient profiling and give a practical approach to identifying factors that should trigger the search for a specific cause of intestinal inflammation. Mimics of IBD include not only infectious causes of colitis-and particular attention is required for patients from endemic areas of tuberculosis-but also vascular diseases, diversion colitis, diverticula or radiation-related injuries, drug-induced inflammation, and monogenic diseases in very-early-onset refractory disease. A superinfection with cytomegalovirus or Clostridium difficile can aggravate intestinal inflammation in IBD, especially in patients who are immunocompromised. Special consideration should be made to the differential diagnosis of perianal disease.

Management of Immune-Related Adverse Events in Patients Treated With Immune Checkpoint Inhibitor Therapy: American Society of Clinical Oncology Clinical Practice Guideline

Purpose To increase awareness, outline strategies, and offer guidance on the recommended management of immune-related adverse events in patients treated with immune checkpoint inhibitor (ICPi) therapy. Methods A multidisciplinary, multi-organizational panel of experts in medical oncology, dermatology, gastroenterology, rheumatology, pulmonology, endocrinology, urology, neurology, hematology, emergency medicine, nursing, trialist, and advocacy was convened to develop the clinical practice guideline. Guideline development involved a systematic review of the literature and an informal consensus process. The systematic review focused on guidelines, systematic reviews and meta-analyses, randomized controlled trials, and case series published from 2000 through 2017. Results The systematic review identified 204 eligible publications. Much of the evidence consisted of systematic reviews of observational data, consensus guidelines, case series, and case reports. Due to the paucity of high-quality evidence on management of immune-related adverse events, recommendations are based on expert consensus. Recommendations Recommendations for specific organ system-based toxicity diagnosis and management are presented. While management varies according to organ system affected, in general, ICPi therapy should be continued with close monitoring for grade 1 toxicities, with the exception of some neurologic, hematologic, and cardiac toxicities. ICPi therapy may be suspended for most grade 2 toxicities, with consideration of resuming when symptoms revert to grade 1 or less. Corticosteroids may be administered. Grade 3 toxicities generally warrant suspension of ICPis and the initiation of high-dose corticosteroids (prednisone 1 to 2 mg/kg/d or methylprednisolone 1 to 2 mg/kg/d). Corticosteroids should be tapered over the course of at least 4 to 6 weeks. Some refractory cases may require infliximab or other immunosuppressive therapy. In general, permanent discontinuation of ICPis is recommended with grade 4 toxicities, with the exception of endocrinopathies that have been controlled by hormone replacement. Additional information is available at www.asco.org/supportive-care-guidelines and www.asco.org/guidelineswiki .

Immunotherapy-Induced Colitis: An Emerging Problem for the Hospitalist

Since their introduction for melanoma treatment, the use of immune checkpoint inhibitors (ICIs) has rapidly expanded. Though their impact on survival is irrefutable, these medications have been associated with autoimmune-like adverse events related to their ability to induce the immune system. One of the most commonly affected organ systems is the gastrointestinal (GI) tract, in which manifestations range from mild diarrhea to severe colitis with intestinal perforation. Because of the increased use of ICIs, hospitalists are caring for an increasing number of patients experiencing their adverse events. We present a case-oriented review of the GI adverse events associated with the use of ICIs to familiarize the hospitalist with their mechanism of action and potential complications and to emphasize the importance of early diagnosis and treatment to decrease morbidity and mortality.