Nivolumab-induced aplastic anemia: A case report and literature review

Fever of unknown origin associated with immune checkpoint inhibitors

Since the approval for the treatment of melanoma in 2014, immune checkpoint inhibitors (ICIs) have revolutionized the therapy pattern across various malignancies. Coinciding with their frequent usage, their adverse effects, including fever, cannot be neglected. In the context of cancer diseases and cancer treatments, fever of unknown origin (FUO), which has long posed a challenge for clinicians in terms of diagnosis and management, brings forth new connotation and significance. In this paper review, we present the concept of ICIs-associated FUO, consider activated immune system and elevated cytokines as common mechanisms by which ICIs induce fever and various immune-related adverse events (irAEs), summarize and compare the primary etiologies of ICI-associated FUO, and compare it with conventional types of FUO.

Antithymocyte globulin for aplastic anemia secondary to pembrolizumab: a case report and review of literature

Aplastic anemia is a rare but potentially serious complication of immune checkpoint inhibitor therapy. The authors present a case of pembrolizumab-induced aplastic anemia that was refractory to steroids but had some hematologic response to modified-dosing antithymocyte globulin (ATG). This is the first reported case of hematological response to ATG for immune checkpoint inhibitor-induced aplastic anemia and the first reported case of modified ATG dosing for this indication. Cases of immune checkpoint inhibitor-induced aplastic anemia and management options are also summarized. Given the high morbidity and mortality associated with ICI-induced aplastic anemia, more data is necessary to guide evidence-based management recommendations.

Immune checkpoint inhibitor-induced aplastic anaemia: Case series and large-scale pharmacovigilance analysis

Introduction: Impressive advances in immunotherapy especially immune checkpoint inhibitors have made great progress in treating multiple cancers but can also cause serious even incurable immune-related adverse events, mostly found in colitis, dermatitis, hepatitis, and thyroiditis patients. Rare autoimmune hematologic toxicities have been reported in the literature, but are poorly described. Aplastic anaemia induced by immune checkpoint inhibitors is a life-threatening autoimmune disease; however, only a few cases have been reported in the literature. Objective: To characterize and evaluate Aplastic anaemia associated with different ICI regimens in public database and review the literature. Methods: We described a case series of patients experiencing Aplastic anaemia while on immune checkpoint inhibitors. We also mined the Food and Drug Administration's Adverse Event Reporting System and used reporting odds ratio, the proportional reporting ratio, the Bayesian confidence propagation neural network and the multi-item gamma Poisson shrinker algorithms to achieve the data of the suspected adverse events of Aplastic anaemia-induced by immune checkpoint inhibitors between January 2011 and June 2022. Results: Thirteen patients with Aplastic anaemia events while on immune checkpoint inhibitors were included in our case series, and seven of them had a fatal outcome. In FAERS, a total of 38 individual case safety reports (immune checkpoint inhibitors) with different ICI regimens were retrieved, of which 25 (65.79%) were reported as monotherapy and 13 (34.2%) had a fatal outcome. The reporting odds ratio was significant for nivolumab (reporting odds ratio 3.05, 95%CI 1.73-5.38), pembrolizumab (reporting odds ratio 2.33, 95%CI 1.16-4.67), avelumab (reporting odds ratio 12.63, 95%CI 3.15-50.62) and ipilimumab/nivolumab (ROR 2.57, 95%CI 1.15-5.72). Conclusion: There is a significant reporting signal of Aplastic anaemia with several ICI agents. Clinicians should raise awareness and monitor this potentially fatal adverse event.

Treatment of patients with cancer using PD‑1/PD‑L1 antibodies: Adverse effects and management strategies (Review)

In 2020, there were an estimated 19.3 million new cancer cases and close to 10 million cancer deaths worldwide. Cancer remains one of the leading causes of death. In recent years, with the continuous improvement of our understanding of tumor immunotherapy, immunotherapeutics, such as immune checkpoint inhibitors, have gradually become a hot spot for tumor treatment. Amongst these, programmed cell death protein 1/programmed cell death protein ligand 1 (PD‑1/PD‑L1) related inhibitors, such as nivolumab and pembrolizumab, atezolizumab, avelumab and durvalumab have been shown to exhibit a high level of efficacy in several types of tumors. It has been confirmed that these inhibitors play an important role in the anti‑tumor process, significantly improving the survival rate of patients and delaying the progress of the underlying cancer. However, its method of therapeutic interference and potential for damaging the immune system has caused concern regarding its suitability. As these adverse effects are caused by an immune response to endogenous tissues, they are designated as immune‑related adverse events (irAEs). In this review, the typical irAEs reported in recent years and the management strategies adopted are highlighted, to serve as a reference in assessing the clinical response to these adverse reactions.

Management and Outcomes of Hematological Immune-related Adverse Events: Systematic Review and Meta-analysis

Data regarding clinical outcomes and management of hematological manifestations of immune checkpoint inhibition (ICI) is limited to case reports, series, and a few retrospective reviews. We aimed to determine the rate of response of hematological immune-related adverse events (irAEs) to immunosuppressive therapy. MEDLINE (OVID), EMBASE, and the Cochrane Central Register of Controlled Trials (CENTRAL) were searched from inception to the present day. Retrospective reports were included without language restrictions. The risk of bias was evaluated with the Cochrane Collaboration's tool. The primary outcome of this study was the rate of response to immunosuppression. Eighty studies (14 case series and 66 individual case reports) were analyzed with a total of 135 patients with ICI-related hematological irAEs. Data analysis showed an average proportional response rate to immunosuppression among hematological irAE entities of 50% (range: 25%-70%). The heterogeneity index (I2) was 0% among reports within each entity. There is a wide spectrum of hematological manifestations to ICI therapy, and to date there is no large randomized-controlled trial data to evaluate the efficacy of treatment strategies for hematological irAEs. We found a variable overall response rate to immunosuppression therapy of around 50%, without statistically significant heterogeneity among different irAE types but significant differences among the different countries of publication. Future studies evaluating the optimal dose and duration of immunosuppressive agents for patients with hematological irAEs should be undertaken.

Current challenges of hematologic complications due to immune checkpoint blockade: a comprehensive review

Immune checkpoint blockade has demonstrated durable clinical benefits in a variety of malignancies. These immune checkpoint inhibitors (ICIs) produce unwanted autoimmune reactions due to an impaired self-tolerance. Hematologic immune-related adverse events (heme-irAEs) have been increasingly reported in the literature with a reported fatality rate of 12%. In this review, we illustrate 3 cases treated at Johns Hopkins Hospital for ICI-induced agranulocytosis, aplastic anemia, and thrombocytopenia. We then summarize the available evidence regarding the incidence and prevalence of heme-irAEs. We identified immune thrombocytopenia and hemolytic anemia as the most commonly reported heme-irAEs which are more commonly observed with nivolumab therapy. Median time to onset of heme-irAEs varies between patients but occurs earlier with CTLA-4 inhibitors than with anti-PD-L1/PD-1 agents. We also describe the current challenges regarding the recurrence of heme-irAEs despite immune checkpoint blockade termination. We provide the available evidence supporting a mixed T-cell and B-cell immune-mediated response. Finally, we review the treatment algorithm of these complications and provide treatment alternatives to steroid-refractory cases.

Aplastic anemia secondary to dual cancer immunotherapies a physician nightmare: case report and literature review

Background

Treatment with immune checkpoint inhibitors has revolutionized cancer treatment over the past several years. Despite their clinical benefits, a wide range of immune-mediated toxicities can be observed including hematological toxicities. Although, the majority can easily be managed, immune-mediated adverse events rarely can be severe and difficult to approach. Herein, we are reporting a case of very severe aplastic anemia secondary to ipilimumab (I) and nivolumab (N) treatment that failed various treatment including intensive immune suppressive therapy.

Case presentation

We described a case of a 45-year old white male, heavy smoker presented to the clinic complaining of left flank pain. He was found to have a metastatic renal cell carcinoma for which he was treated with dual immunotherapy and later complicated by severe immune related adverse events. The patient later died after failing intensive immune suppressive therapy.

Conclusion

Immunotherapy has become an established pillar of cancer treatment improving the prognosis of many patients with variant malignancies. Yet, lethal adverse events can occur in rare cases. It is our duty, as physicians, to remain alert and cautious.

A Systematic Review of the Tumor-Infiltrating CD8+ T-Cells/PD-L1 Axis in High-Grade Glial Tumors: Toward Personalized Immuno-Oncology

Based on preclinical findings, programmed death-ligand 1 (PD-L1) can substantially attenuate CD8⁺ T-cell-mediated anti-tumoral immune responses. However, clinical studies have reported controversial results regarding the significance of the tumor-infiltrating CD8⁺ T-cells/PD-L1 axis on the clinical picture and the response rate of patients with high-grade glial tumors to anti-cancer therapies. Herein, we conducted a systematic review according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) statements to clarify the clinical significance of the tumor-infiltrating CD8⁺ T-cells/PD-L1 axis and elucidate the impact of this axis on the response rate of affected patients to anti-cancer therapies. Indeed, a better understanding of the impact of this axis on the response rate of affected patients to anti-cancer therapies can provide valuable insights to address the futile response rate of immune checkpoint inhibitors in patients with high-grade glial tumors. For this purpose, we systematically searched Scopus, Web of Science, Embase, and PubMed to obtain peer-reviewed studies published before 1 January 2021. We have observed that PD-L1 overexpression can be associated with the inferior prognosis of glioblastoma patients who have not been exposed to chemo-radiotherapy. Besides, exposure to anti-cancer therapies, e.g., chemo-radiotherapy, can up-regulate inhibitory immune checkpoint molecules in tumor-infiltrating CD8⁺ T-cells. Therefore, unlike unexposed patients, increased tumor-infiltrating CD8⁺ T-cells in anti-cancer therapy-exposed tumoral tissues can be associated with the inferior prognosis of affected patients. Because various inhibitory immune checkpoints can regulate anti-tumoral immune responses, the single-cell sequencing of the cells residing in the tumor microenvironment can provide valuable insights into the expression patterns of inhibitory immune checkpoints in the tumor micromovement. Thus, administrating immune checkpoint inhibitors based on the data from the single-cell sequencing of these cells can increase patients’ response rates, decrease the risk of immune-related adverse events development, prevent immune-resistance development, and reduce the risk of tumor recurrence.

Glioblastoma multiforme: a multi-omics analysis of driver genes and tumour heterogeneity

Glioblastoma (GBM) is the most aggressive and common brain cancer in adults with the lowest life expectancy. The current neuro-oncology practice has incorporated genes involved in key molecular events that drive GBM tumorigenesis as biomarkers to guide diagnosis and design treatment. This study summarizes findings describing the significant heterogeneity of GBM at the transcriptional and genomic levels, emphasizing 18 driver genes with clinical relevance. A pattern was identified fitting the stem cell model for GBM ontogenesis, with an upregulation profile for MGMT and downregulation for ATRX, H3F3A, TP53 and EGFR in the mesenchymal subtype. We also detected overexpression of EGFR, NES, VIM and TP53 in the classical subtype and of MKi67 and OLIG2 genes in the proneural subtype. Furthermore, we found a combination of the four biomarkers EGFR, NES, OLIG2 and VIM with a remarkable differential expression pattern which confers them a strong potential to determine the GBM molecular subtype. A unique distribution of somatic mutations was found for the young and adult population, particularly for genes related to DNA repair and chromatin remodelling, highlighting ATRX, MGMT and IDH1. Our results also revealed that highly lesioned genes undergo differential regulation with particular biological pathways for young patients. This multi-omic analysis will help delineate future strategies related to the use of these molecular markers for clinical decision-making in the medical routine.

Society for Immunotherapy of Cancer (SITC) clinical practice guideline on immune checkpoint inhibitor-related adverse events

Immune checkpoint inhibitors (ICIs) are the standard of care for the treatment of several cancers. While these immunotherapies have improved patient outcomes in many clinical settings, they bring accompanying risks of toxicity, specifically immune-related adverse events (irAEs). There is a need for clear, effective guidelines for the management of irAEs during ICI treatment, motivating the Society for Immunotherapy of Cancer (SITC) to convene an expert panel to develop a clinical practice guideline. The panel discussed the recognition and management of single and combination ICI irAEs and ultimately developed evidence- and consensus-based recommendations to assist medical professionals in clinical decision-making and to improve outcomes for patients.

Increased Incidence of Venous Thromboembolism with Cancer Immunotherapy

BACKGROUND

Cancer immunotherapy is associated with several immune-related adverse events, but the relationship between immunotherapy and venous thromboembolism has not been thoroughly studied.

METHODS

We conducted a retrospective cohort study of 1,686 patients who received immunotherapy for a variety of malignancies to determine the incidence of venous thromboembolism and the impact of venous thromboembolism on survival. To examine the potential role of inflammation in venous thromboembolism, we also profiled immune cells and plasma cytokines in blood samples obtained prior to initiation of immunotherapy in a sub-cohort of patients treated on clinical trials who subsequently did (N = 15), or did not (N = 10) develop venous thromboembolism.

FINDINGS

Venous thromboembolism occurred while on immunotherapy in 404/1686 patients (24%) and was associated with decreased overall survival [HR=1.22 (95% CI 1.06-1.41), p<0.008]. Patients that developed venous thromboembolism had significantly higher pretreatment levels of myeloid-derived suppressor cells (5.382 ± 0.873 vs. 3.341 ± 0.3402, mean ± SEM; p=0.0045), interleukin 8 (221.2 ± 37.53 vs. 111.6 ± 25.36, mean ± SEM; p=0.016), and soluble vascular cell adhesion protein 1 (1210 ± 120.6 vs. 895.5 ± 53.34, mean ± SEM; p=0.0385).

CONCLUSIONS

These findings demonstrate that venous thromboembolism is an underappreciated and important immune-related adverse event associated with cancer immunotherapy, and may implicate an interleukin 8 and myeloid-derived suppressor cell-driven pathway in pathogenesis.

Hematological immune related adverse events after treatment with immune checkpoint inhibitors

INTRODUCTION

With the increasing use of checkpoint inhibitors, rare immune-related adverse events (irAE) are being identified. Haematological irAE (hem-irAE) are difficult to treat and have shown high mortality rates. In order to improve side-effect management for these potentially life-threatening events, we analysed frequency, severity and outcomes.

PATIENTS AND METHODS

Patients who developed hem-irAE while being treated with immune checkpoint inhibitors (ICI) therapy were retrospectively identified from 18 international cancer centres.

RESULTS

In total, more than 7626 patients treated with ICI were screened, and 50 patients with hem-irAE identified. The calculated incidence amounts to 0.6% and median onset was 6 weeks after the ICI initiation (range 1-128 weeks). Thrombocytopenia and leucopaenia were the most frequent hem-irAE with 34% (17/50) and 34% (17/50), respectively, followed by anaemia 28% (14/50), hemophagocytic lymphohistiocytosis (4% (2/50)), aplastic anaemia (2% (1/50)), acquired haemophilia A (2% (1/50)) and coagulation deficiency (2% (1/50)). Simultaneous thrombocytopenia and neutropenia occurred in two patients, concurrent anaemia and thrombocytopenia in one patient. Other than cessation of ICI (in 60%) and corticosteroids (in 78%), treatment included second-line immunosuppression in 24% of cases. Events resolved in 78% (39/50), while 18% (9/50) had persistent changes, and 2% (1/50) had fatal outcomes (agranulocytosis).

CONCLUSION

Hem-irAE can affect all haematopoietic blood cell lineages and may persist or even be fatal. Management may require immunosuppression beyond corticosteroids. Although these irAE are rare, treating physicians should be aware, monitor blood counts regularly and promptly act upon detection.

A case of non-small cell lung cancer with danazol-dependent aplastic anemia induced by pembrolizumab

Programmed cell death protein 1 immune checkpoint inhibitor is an effective treatment for non-small cell lung cancer. Although hematological immune-related adverse events induced by antiprogrammed-cell-death-protein-1 immunotherapy have been reported, they are rare, and there remain many unknowns. We report the case of a 77-year-old woman with non-small cell lung cancer and pembrolizumab-induced danazol-dependent aplastic anemia. Sixteen days after she received pembrolizumab with carboplatin and pemetrexed as first-line treatments, she developed pancytopenia, including severe thrombocytopenia (1 × 10⁹/L) with oral bleeding, epistaxis, and systemic purpura. We initially diagnosed immune-related thrombocytopenia based on an elevated level of platelet-associated immunoglobulin G (922ng/10⁷ cells), but her thrombocytopenia was refractory to prednisolone (1mg/kg) and thrombopoietin receptor agonists. We eventually diagnosed aplastic anemia based on the findings of bone marrow hypoplasia. Treatment with cyclosporine and danazol 300mg (7.5mg/kg) was initiated. Eighteen days later, her blood cell count increased, and we reduced danazol to 100mg. Twenty-four days after the reduction of danazol, her platelet count dropped again to 14 × 10⁹/L; subsequently, increasing danazol improved her platelet count in a few days. Although aplastic anemia was recovered, she died owing to lung cancer progression. In this case, the thrombocytopenia was noticeable initially; however, pancytopenia appeared a month later, and we diagnosed her with aplastic anemia. Platelet counts improved rapidly with the use of danazol. No effective treatment has yet been established for aplastic anemia induced by antiprogrammed-cell-death-protein-1 immunotherapy, but our case suggests that danazol is an effective therapy.

Diagnosis and Management of Hematological Adverse Events Induced by Immune Checkpoint Inhibitors: A Systematic Review

There has been less volume of literature focusing on the Immune-related Hematological Adverse Drug Events (Hem-irAEs) of Immune Checkpoint Inhibitors (ICPis) in cancer patients. Furthermore, there has been no consensus about the management of hematological toxicity from immunotherapy in the recently published practice guidelines by the European Society for Medical Oncology (ESMO). We conducted a systematic review of case reports/series to describe the diagnosis and management of potentially rare and unrecognized Hem-irAEs. We searched Medline, OVID, Web of Science for eligible articles. Data were extracted on patient characteristics, Hem-irAEs, and management strategies. We performed quality assessment using the Pierson-5 evaluation scheme and causality assessment using the Naranjo scale. Our search retrieved 49 articles that described 118 cases. The majority of patients had melanoma (57.6%) and lung cancer (26.3%). The most common Hem-irAEs reported with ICPis (such as nivolumab, ipilimumab, and pembrolizumab) were thrombocytopenia, hemolytic and aplastic anemias. Less reported adverse events included agranulocytosis and neutropenia. Steroids were commonly used to treat these adverse events with frequent success. Other used strategies included intravenous immunoglobulins (IVIG), rituximab, and transfusion of blood components. The findings of this review provide more insights into the diagnosis and management of the rarely reported Hem-irAEs of ICPis.

Metabolic consequences of immune checkpoint inhibitors: A new challenge in clinical practice

Treatment of oncologic patients has progressed greatly the last few years with the development of immune checkpoint inhibitors (ICPIs). These drugs are associated with the immune system and, thus, may cause side effects of immune origin, the so called immune related adverse events (irAEs). Immune related AEs may actually affect all organs and systems and frequently resemble clinical entities commonly encountered in clinical practice. As ICPIs have improved both quality of life and life expectancy, clinicians of various specialties may need to deal with irAEs in their everyday practice. Therefore, they should be able to recognize them timely and treat them accordingly. Herein, we review the pathophysiology, clinical manifestations and treatment of irAEs.

Challenges in diagnosis and management of neutropenia upon exposure to immune-checkpoint inhibitors: meta-analysis of a rare immune-related adverse side effect

BACKGROUND

Cancer immunotherapy via immune-checkpoint inhibition (ICI) by antibodies against cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and cell death protein 1 (PD-1) have significantly improved the outcome of metastasized melanoma and of a rapidly increasing number of other cancer types. The anti-tumor effect is often accompanied by immune-related adverse events (irAE). Hematological irAE, specifically neutropenia, are rarely observed. However, neutropenia is associated with high morbidity and mortality due to infection complications. Thus, early detection and treatment is crucial.

METHODS

We present the clinical course of two patients with severe neutropenia after ICI therapy and demonstrate the difficulty of the diagnosis when a comedication of metamizole, a well-known analgesic drug used to treat cancer pain, is present. Further, we provide a comprehensive descriptive and statistical analysis of published data on diagnostics, treatment and infection complication in patients with at least grade 4 neutropenia by a systematic database search.

RESULTS

Finally, 34 patients were analyzed, including the two case reports from our cohort. The median onset of neutropenia was 10.5 weeks after first ICI administration (interquartile range: 6 weeks). In 76% (N = 26), a normalization of the neutrophil count was achieved after a median duration of neutropenia of 13 days. In a subsample of 22 patients with detailed data, the infection rate was 13%, proven by positive blood culture in 3 cases, but 68% (N = 15) presented with fever > 38 °C. Treatment regime differed relevantly, but mainly included G-CSF and intravenous corticosteroids. Death was reported in 14 patients (41%), 3 of whom (9%) were associated with hematological irAE but only two directly associated with neutropenia.

CONCLUSION

With an increasing number of cancer patients eligible to ICI therapy, the incidence of severe hematological toxicities may rise substantially over the next years. Clinicians working in the field of cancer immune therapies should be aware of neutropenia as irAE to provide immediate treatment.

Immune-mediated adverse effects of immune-checkpoint inhibitors and their management in cancer

Within the past decade, immune-checkpoint inhibitors (ICPIs), including anti-programmed cell death 1 (PD-1), anti-programmed cell death 1 ligand 1 (PD-L1), and anti-cytotoxic T lymphocyte antigen 4 (CTLA-4) antibodies, are undoubtfully the most remarkable advances in cancer therapy. The immune responses are modulated by these ICPIs via blocking the inhibitory PD-1/PD-L1 path and result in immune activation in the suppressive microenvironment of the tumor. While ICPIs result in benefits for numerous patients with malignancy and lead to disease control and survival, toxicity and safety problems have emerged as well. Although immune mediated adverse effects due to ICPIs could involve any organ system, skin, endocrine glands, and gastrointestinal tract, are one of the most commonly affected. Fortunately, in most of the cases, these immune‑mediated adverse effects (imAEs) are manageable, while in some cases these toxicities are fulminant and fatal and lead to the withdrawal of treatment. Numerous attempts have been started and are continuing to reduce the incidence rate of imAEs. Further studies are required for a better understanding of these imAEs, decrease the occurrence, and lighten the severity. In this work, we overview the imAEs and also, highlight the most important aspects of the imAEs management.

Clinical diagnosis and treatment recommendations for immune checkpoint inhibitor-related hematological adverse events

Immune checkpoint inhibitors (ICIs) are able to reactivate the immune system, thereby enhancing the anti‐tumor effects. However, over‐activated T cells may induce immune‐related adverse events (irAEs). Hematological irAEs are rarely reported which mainly represent monolineage cytopenia or pancytopenia, including autoimmune hemolytic anemia (AIHA), immune thrombocytopenia (ITP), neutropenia and aplastic anemia, sometimes even life‐threatening diseases such as hemophagocytic lymphohistiocytosis. Here, the clinical manifestations of hematological irAEs are summarized and recommendations for diagnosis and treatment proposed.

Key points

Toxicity of tumor immune checkpoint inhibitors-more attention should be paid

In recent years, immunotherapy, especially immune checkpoint inhibitors (ICIs), has achieved amazing results in the treatment of lung cancer, melanoma, renal clear cell carcinoma and other malignant tumors. Although ICIs have achieved significant efficacy in tumor treatment, the immune-related adverse events (irAEs) caused by non-specific immune activation of ICIs can directly affect the result of treatment, even threaten the life of patients. The most common form of irAEs involve the skin, lung, colon, liver and endocrine organs. However, it is noticeable that although irAEs of some organs are more common, actually any organ and tissue are likely to be affected, because of non-specific activation of the immune system. Other tissues and organs, though rare, can be more severe and even fatal, such as neurological disorders and myocarditis. Therefore, effective management of irAEs is of great importance for the efficacy of immunotherapy. This review is focused on the morbidity, clinical manifestations, diagnosis and treatment of tumor immune toxic effects.

Toxicities associated with checkpoint inhibitors-an overview

Immunotherapy has an increasing role in the management of cancer, both in metastatic disease and as an adjuvant therapy. However, sensitization of the immune system with checkpoint inhibitors comes with a unique side effect profile. Full appreciation of this can take some time to emerge as some adverse events are rare, or can be subtle and potentially overlooked. Clinician awareness of these side effects can be particularly important in patients with pre-existing autoimmune conditions. Here we describe common symptoms and diagnostic strategies for organ-specific side effects of anti-CTLA-4 and anti-PD-1/PD-L1 immunotherapy agents.

[Clinical Diagnosis and Treatment Recommendations for Immune Checkpoint Inhibitor-related Hematological Adverse Events]

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Safety and Tolerability of Immune Checkpoint Inhibitors (PD-1 and PD-L1) in Cancer

Immunotherapy has emerged in recent years and has revolutionized the treatment of cancer. Immune checkpoint inhibitors, including anti-cytotoxic T lymphocyte antigen-4 (CTLA-4), anti-programmed cell death-1 (PD-1) and anti-programmed cell death ligand-1 (PD-L1) agents, are the first of this new generation of treatments. Anti-PD-1/PD-L1 agents target immune cells by blocking the PD-1/PD-L1 pathway. This blockade leads to enhancement of the immune system and therefore restores the tumour-induced immune deficiency selectively in the tumour microenvironment. However, this shift in the balance of the immune system can also produce adverse effects that involve multiple organs. The pattern of toxicity is different from traditional chemotherapy agents or targeted therapy, and there is still little experience in recognizing and managing it. Thus, toxicity constitutes a real clinical management challenge and any new alteration should be suspected of being treatment-related. The most common toxicities occur in the skin, gastrointestinal tract, lungs, and endocrine, musculoskeletal, renal, nervous, haematologic, cardiovascular and ocular systems. Immune-mediated toxic effects are usually manageable, but toxicities may sometimes lead to treatment withdrawal, and even fulminant and fatal events can occur. Oncologists need to collaborate with internists, clinical immunologists and other specialists to understand, manage and prevent toxicity derived from immunotherapy. This review focuses on the mechanisms of toxicity of anti-PD-1/PD-L1 agents, and its diagnosis and management.

Unexpected serious aplastic anemia from PD-1 inhibitors: beyond what we know

INTRODUCTION

The recent introduction of checkpoint inhibitor-based immunotherapy has revolutionized the treatment of advanced lung cancers, becoming standard of care in both first- and second-line treatment. New types of toxicity are emerging with the increasingly widespread use of these inhibitors.

CASE PRESENTATION

We describe a case of aplastic anemia in a patient with stage IV non-small cell lung cancer after a single administration of nivolumab.

CONCLUSIONS

Several similar case reports reported in literature show an increasing rate of toxicities from immunotherapy in this setting. These real-world data provide an insight into patient outcomes and treatment decisions being made in clinical practice.

Hematological Side Effects of Immune Checkpoint Inhibitors: The Example of Immune-Related Thrombocytopenia

Immune-related hematological adverse events are amongst the rare but potentially life-threatening complications of immune checkpoint inhibitors. The spectrum of these toxicities is broadening as the number of patients exposed to these agents is increasing. Yet, they are still relatively unknown to many clinicians, possibly due to a lack of specific diagnostic criteria, which poses a challenge for their recognition and proper reporting, and partly due to their low incidence, often too low to be noted in most clinical trial publications. Since early detection and prompt intervention are crucial to prevent fatal consequences, it is of outmost importance that medical staff and patients be aware of these potential toxicities and learn to recognize and treat them adequately. This publication outlines strategies and offers guidance on the detection, diagnosis, risk assessment, monitoring and management of immune-related thrombocytopenia, a relatively common example of immune-related hematological toxicity of immune checkpoint inhibitors.

Checkpoint Inhibitors

BACKGROUND

Treatment with checkpoint inhibitors such as anti-programmed death-1 (anti-PD-1), anti-PD-ligand 1 (anti-PD-L1), and anti-cytotoxic T-lymphocyte antigen-4 (anti-CTLA-4) antibodies can prolong the survival of cancer patients, but it also induces autoimmune side effects in 86-96% of patients by activating the immune system. In 17-59% of patients, these are severe or even life-threatening.

METHODS

This review is based on pertinent articles retrieved by a search in PubMed and on an evaluation of a side-effect registry.

RESULTS

Checkpoint-inhibitor-induced autoimmune side effects manifest themselves in all organ systems, most commonly as skin lesions (46-62%), autoimmune colitis (22-48%), autoimmune hepatitis (7-33%), and endocrinopathies (thyroiditis, hypophysitis, adrenalitis, diabetes mellitus; 12-34%). Rarer side effects include pneumonitis (3-8%), nephritis (1-7%), cardiac side effects including cardiomyositis (5%), and neurological side effects (1-5%). Severe (sometimes lethal) side effects arise in 17-21%, 20-28%, and 59% of patients undergoing anti-PD-1 and anti- CTLA-4 antibody treatment and the approved combination therapy, respectively. With proper monitoring, however, these side effects can be recognized early and, usually, treated with success. Endocrine side effects generally require long-term hormone substitution. Patients who have stopped taking checkpoint inhibitors because of side effects do not show a poorer response of their melanoma or shorter survival in comparison to patients who continue to take checkpoint inhibitors.

CONCLUSION

The complex management of checkpoint-inhibitor-induced side effects should be coordinated in experienced centers. The creation of an interdisciplinary "tox team" with designated experts for organ-specific side effects has proven useful. Prospective registry studies based on structured documentation of side effects in routine clinical practice are currently lacking and urgently needed.

Nivolumab Induced Lethal Aplastic Anemia in a Patient with Metastatic Melanoma

Nivolumab is an active treatment in patients with metastatic melanoma. We report a case of a patient with metastatic malignant melanoma who was given nivolumab as an advanced-line treatment. She received nivolumab 3 mg/kg every 2 weeks for 4 cycles and developed aplastic anemia. To the best of our knowledge, there are only three published case reports that have shown aplastic anemia in patients who have been treated by immunotherapy. This is the first report of a lethal aplastic anemia during nivolumab monotherapy in a metastatic melanoma patient.

Aplastic anemia secondary to nivolumab and ipilimumab in a patient with metastatic melanoma: a case report

Background

Immune checkpoint blockade (ICB) is becoming an increasingly prevalent strategy in the clinical realm of cancer therapeutics. With more patients being administered ICB for a host of tumor types, the scope of adverse events associated with these drugs will likely grow. Here we report a case of aplastic anemia (AA) in a patient with metastatic melanoma secondary to dual ICB therapy. To our knowledge, this is only the second case of AA secondary to dual ICB in the literature, and the first to have a positive patient outcome.

Case presentation

A 51-year old male with metastatic melanoma was started on dual immune checkpoint blockade, in the form ipilimumab (3 mg/kg) and nivolumab (1 mg/kg). Two weeks following the second cycle, he presented to the emergency department with profound polypipsia, polyuria and fatigue. The patient was diagnosed with diabetic ketoacidosis secondary to immune therapy induced type-1 diabetes and was admitted to the ICU. While in hospital the patient developed a symptomatic anemia and neutropenia. A bone marrow biopsy revealed a markedly hypocellular marrow with trinlineage hypoplasia with no evidence of myelodysplasia, neoplasm or excess blasts. Flow cytometry revealed an inverted CD4⁺:CD8⁺ ratio and an absence of hematogones. Taken together the presumed etiology was AA secondary to immunotherapy. The patient was subsequently started in IV methylprednisone 70 mg/day for 8 days, followed by a prednisone taper. This intervention rectified the bicytopenia and to date the patient has shown stable blood counts.

Conclusion

With the use of ICBs becoming increasingly prevalent in the clinical arena, the number of patients presenting with immune-related adverse events will likely increase. The current case illustrates the need to be vigilant when managing cancer patients receiving ICB. The resolution of this patient’s AA with corticosteroids highlights the value of early detection and appropriate treatment of these rare immune-mediated adverse events.