Development of Hemolytic Anemia in a Nivolumab-Treated Patient with Refractory Metastatic Squamous Cell Skin Cancer and Chronic Lymphatic Leukemia

Rare Immune-Related Adverse Events (irAEs): Approach to Diagnosis and Management

Immune checkpoint inhibitors (ICIs) have revolutionised the treatment landscape across many solid organ malignancies and form part of routine clinical practice in many tumours. As indications for monotherapy, doublet therapy and combination approaches with chemotherapy and targeted agents expand, clinicians must be aware of the wide range of possible immune-related adverse events (irAEs). Common toxicities, including rash, colitis, hepatitis and pneumonitis are well described in the literature, and have established diagnostic and management algorithms. Rarer toxicities, often with an incidence of less than 1%, are less defined. These syndromes can be poorly recognised, may take on a fulminant course and do not have established or evidence-based diagnostic and management strategies. As such, patients may experience increased morbidity, mortality and poorer outcomes, related both to these irAEs as well as how the treatment of these may affect the management of their underlying malignancy. In this review, we aim to explore the incidence, potential biomarkers, pathogenesis, diagnostic work-up and clinical sequelae of a selection of uncommon irAEs, with a focus on myocarditis, neurological and haematologic syndromes. Further prospective research is required to accurately define the incidence and pathogenesis of these conditions, with the aim of increasing clinician awareness of rare irAEs and to assist with a more personalised and mechanism-based approach to these syndromes.

Immune Checkpoint Inhibitor-Induced Pure Red Cell Aplasia: A Review of 2 Cases in Metastatic Melanoma

BACKGROUND Immunotherapy is a novel treatment offering an alternative to traditional chemotherapeutic agents for different malignancies. Hematologic adverse reactions (HARs) related to immune checkpoint inhibitors (ICIs) are uncommon. Pure red cell aplasia (PRCA) is a rare hematologic complication of ICI therapy in metastatic melanoma with significant mortality risk despite treatment with steroids or immunosuppressive therapy. For unexplained acute anemia after exclusion of other causes, performing bone marrow biopsy is imperative to diagnose PRCA and rule out involvement of bone marrow by primary tumor. HARs can occur during ICI therapy or even after ICI therapy is stopped. ICI rechallenge, even after the development of HARs, is considered in some patients with good response to treatment of HARs from ICIs. Recurrence of HARs with the same or different type of reaction is seen in some patients. CASE REPORT Two cases of ICI-induced PRCA were confirmed on bone marrow biopsy after dual ICI treatment with nivolumab and ipilimumab in metastatic melanoma. In case 2, PRCA was successfully treated with steroids and later rechallenged with single-agent nivolumab, causing mild ICI-induced immune thrombocytopenia, which did not require treatment with steroids. CONCLUSIONS It is crucial to increase clinician awareness of the possibility of PRCA development not only during treatment with ICI but also after finishing treatment with ICI; there is high mortality associated with missing an opportunity to diagnose and treat PRCA on time with favorable results. ICI rechallenge can be considered in patients who showed response to immunotherapy, especially those with limited alternative therapeutic options.

Auto-immune hemolytic anemia and hemophagocytic lymphohistiocytosis as immune-related adverse event in patients with metastatic melanoma and concurrent chronic lymphocytic leukemia: a case series and literature review

Auto-immune hemolytic anemia (AIHA) and hemophagocytic lymphohistiocytosis (HLH) are both rare immune-related adverse events (irAEs) following treatment with immune checkpoint inhibitors. Consensus treatment guidelines are currently lacking. Patients with a solid malignancy and a concurrent lymphoproliferative disorder, such as chronic lymphocytic leukemia (CLL), might be more prone to develop hematological irAEs. We report the case history of two patients, diagnosed with CLL, who during treatment for metastatic melanoma with nivolumab, a PD-1 immune checkpoint blocking mAb, developed AIHA and HLH in combination with AIHA. Furthermore, we provide a review of the literature on published cases of immune-related AIHA and HLH and their correlation with CLL.

Hematological toxicities of immune checkpoint inhibitors and the impact of blood transfusion and its microbiome on therapeutic efficacy and recipient's safety and survival outcome:A systematic narrative appraisal of where we are now!

Classically, patients with solid and hematologic malignancies have been treated with a combination of chemotherapy with or without a holistic targeted strategy using approved conventional therapy. While the evidence-based use of Immunomodulatory drugs and Immune checkpoint inhibitors (ICIs), including those targeting the PD-1, PD-L1 and CTLA-4, have reshaped the treatment paradigm for many malignant tumors and significantly stretched the life expectancy of patients, as for any interventional therapy, the rise in ICI applications, was associated with the observation of more immune-related hematological adverse events. Many of these patients require transfusion support during their treatment in line with precision transfusion. It has been presumed that transfusion-related immunomodulation (TRIM) and the microbiome can pose immunosuppressive effects on the recipients. Looking to the past and beyond and translating available data into practice in the evolving role of pharmaceutical therapy to ICI-receiving patients, we performed a narrative review of the literature on the immune-related hematological adverse events of ICIs, immunosuppressive mechanisms linked to blood product transfusions, as well as the detrimental impact of transfusions and its related microbiome on the sustained efficacy of ICIs and the patients' survival outcomes. Recent reports are pointing to the negative impact of transfusion on ICI response. Studies have concluded that packed RBC [PRBC] transfusions lead to an inferior progression-free and overall survival in patients with advanced cancer receiving ICIs, even after adjustments for other prognostic variables. The attenuation of the effectiveness of immunotherapy likely results from the immunosuppressive effects of PRBC transfusions. It is, therefore, wise to look retrospectively and prospectively at the impact of transfusion on ICI effects and adopt, in the interim, a restrictive transfusion strategy, if applicable, for those patients.

Combined response of advanced cutaneous squamous cell carcinoma and renal cell carcinoma to immunotherapy: a case report

Immune checkpoint inhibitors have significantly improved the therapeutic scenario of many different advanced malignancies and could be an effective treatment strategy in synchronous or metachronous tumors. The authors describe the clinical case of a patient who experienced a long-lasting response of his metastatic renal cell carcinoma and an optimal response of his locally advanced cutaneous squamous cell carcinoma to immunotherapy. The systemic treatment was chosen based on a literature review of several clinical reports, since there was no prospective study on anti-PD-1 blockade activity in cutaneous squamous cell carcinoma when the patient started the treatment. This clinical case supports the growing evidence for immunotherapy as a valid treatment option across different types of advanced tumors.

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.

Nivolumab-Induced Autoimmune Haemolytic Anaemia and Safety of Subsequent Use of Ipilimumab: A Case Report

Autoimmune haemolytic anaemia (AIHA) is a rare immune-related adverse event and appears to be more common with anti-PD1/PDL1 than anti-CTLA4. Little is known about the safety of re-treating with anti-PD1/PDL1 or changing to anti-CTLA4. We present a case of grade 4 AIHA due to nivolumab (PD1-inhibitor) treatment in a patient with melanoma for adjuvant setting after surgery and the safeness of subsequent treatment with ipilimumab (anti-CTLA4). After the remission of AIHA with steroids, ipilimumab was started with the rationale of its different mechanism of action. Fortunately, AIHA did not recur. The mechanism by which checkpoint inhibitors cause AIHA is likely by augmenting or redirecting immune surveillance, especially by activating pre-existing red blood cell autoantibodies, but further studies must be done. To our knowledge, this is the first case published in the literature with the change of immunotherapy treatment to anti-CTLA4.

Association Between RBC Antigen Allo-Antibodies and Immune-Related Adverse Events During Immune Checkpoint Inhibitor Treatment for Advanced Cancers

Introduction

Immune checkpoint inhibitors (ICI) have become a primary treatment modality for patients with a variety of malignancies. Given their increasing use, it is essential to be familiar with their immune-related adverse events (irAEs). Here we report a severe case of autoimmune hemolytic anemia (AIHA) associated with cold agglutinin precipitated by pembrolizumab, and a retrospective study of patients treated with ICI utilizing an institutional database where we analyzed the patterns of anti-RBC testing and their ability to predict irAE.

Methods

Patients treated with at least one dose of ICI (PD-1, PD-L1, CTLA-4 inhibitors) for advanced cancer between November 2012 and September 2017 at our institution were included. Electronic Medical Records were reviewed to abstract data. Medians and 95% CIs were estimated using Kaplan–Meier method and differences compared using the Log Rank test. Fisher’s exact test and Chi square test were used to analyze clinical associations.

Results

We identified 1065 patients who received at least one dose of ICI: 180/1065 (17%) underwent direct antiglobulin test (DAT) or allo-antibody (alloAb) testing at any time; 127/1065 (12%) had either DAT or alloAb testing pre-ICI; 129 had either DAT or alloAb testing after ICI initiation; and 76 had either DAT or alloAb testing at both time points. There was a significant association between positive alloAb pre-ICI and the development of irAE while on ICI (p = 0.04).

Conclusion

Given the increasing use of ICI, oncologists should be aware of potential irAEs with ICI. We found an association between the presence of an alloAb pre-ICI and the development of irAE, indicating that this previous non-self antigen response may predict immune adverse events. A larger prospective study is needed for systematic evaluation of the association between alloAb testing and irAE, and whether routine testing may inform clinical decision-making for patients.

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.

Pembrolizumab-induced pancytopenia in a patient with squamous cell lung cancer

Immune checkpoint inhibitors (ICIs) are reportedly effective against many kinds of neoplasm, but may be responsible for several kinds of immune‐related adverse events (irAEs). Among these irAEs, the incidence of myelosuppression due to ICIs is relatively low. Corticosteroids are needed to control most cases of myelosuppression. Here, we report an 88‐year‐old woman with squamous cell lung cancer who was administered pembrolizumab. After five cycles of pembrolizumab, she developed severe pancytopenia. The pancytopenia improved under observation without steroid administration after cessation of pembrolizumab. During recovery from this irAE, the patient also maintained long‐term antitumor efficacy.

Key points

Significant findings of the study

There are several kinds of immune‐related adverse events. We encountered a case of pembrolizumab‐induced pancytopenia with squamous cell lung cancer.

What this study adds

Corticosteroids are needed to control most cases of myelosuppression induced by ICIs, but pancytopenia induced by pembrolizumab in our case improved without steroids.

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

Immunotherapy in metastatic melanoma: a novel scenario of new toxicities and their management

Checkpoint inhibitors can cause an imbalance in immune tolerance that may clinically manifest as immune-related adverse events (irAEs). These events may involve many organs and tissues, including the skin, gastrointestinal (GI) tract, liver, endocrine system, kidneys, central nervous system (CNS), eyes and lungs. The incidence of irAEs appears to be lower with anti-programmed death antigen-1/programmed death antigen-ligand-1 agents than with the anti-cytotoxic T-lymphocyte-associated protein-4 antibody ipilimumab. Combined immunotherapy does not appear to be associated with novel safety signals compared with monotherapy, but more organs may be involved. Increased experience and the use of algorithms for the most common irAEs have resulted in severe toxicity and related deaths being reduced. However, continuous vigilance, especially regarding less common events, is needed to better characterize the wide spectrum of clinical manifestations.

Pembrolizumab-associated autoimmune haemolytic anaemia

Treatment paradigms have recently changed with the introduction of immunotherapy; autoimmune toxicities that can arise are frequently very different from the more familiar chemotherapy toxicities. We present a clinical case of autoimmune haemolytic anaemia (AIHA) secondary to pembrolizumab occurring in a 73-year-old male patient being treated for lung adenocarcinoma, who had received 13 cycles of pembrolizumab. Treatment was immediately stopped and he was treated with high dose steroids to which he responded both clinically and biochemically. There have been prior reports of immunotherapy-associated AIHA with the use of cytotoxic T-lymphocyte-associated antigen-4 inhibitors, such as ipilimumab, but very few reports of programmed death-1 (PD-1)/programmed death-ligand 1 (PDL-1) inhibitor associated AIHA. We highlight a rare case of AIHA as an adverse effect of pembrolizumab, a PD-1 inhibitor. Although unusual, it is important to be vigilant for haematological immune-related adverse events.

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

免疫检查点抑制剂能够重新激活免疫系统，启动肿瘤杀伤，而T细胞过度激活导致各种免疫相关不良反应。血液系统不良反应报道少见，主要表现为单系或多系血细胞减少，包括自身免疫性溶血性贫血、免疫性血小板减少症、中性粒细胞减少症，严重时表现为再生障碍性贫血，甚至可能致命，如噬血细胞淋巴组织细胞增多症。我们将总结免疫检查点抑制剂相关血液不良反应的临床特点，并对诊断和治疗给予建议。

Haematological immune-related adverse events with immune checkpoint inhibitors, how to manage?

Immune checkpoint inhibitors (ICIs) are changing the treatments of many patients with cancer. These immunotherapies are generally better tolerated than chemotherapy, and their adverse events are immune-related mimicking autoimmune or inflammatory conditions. Although these immune-related adverse events mainly affect the skin, endocrine glands, digestive tract, joints, liver or lungs, all the organs can be theoretically affected, and the haematopoietic system is not spared. This review of the literature will focus on the haematological immune-related adverse events (Haem-irAEs). By reviewing the largest clinical trials of ICIs, we estimate the frequency of Haem-irAEs at 3.6% for all grades and 0.7% for grades III-IV. Frequency of Haem-irAEs of all grades was found to be higher with anti-programmed cell death 1 (4.1%) or anti-programmed cell death ligand 1 (4.7%) than with anti-cytotoxic T-lymphocyte-associated protein 4 (0.5%) (p < 0.0001). From the 63 cases with Haem-irAEs reported in the literature, the mean time to the onset was found to be 10 weeks after ICI initiation, and the large range for occurrence (1-84 weeks) and the regular incidence suggest that Haem-irAEs could occur at any time after ICI therapy. Among the 63 reported cases with Haem-irAEs, the distribution was immune thrombocytopenia (n = 18, 29%), pancytopenia or immune aplastic anaemia (n = 12, 19%), neutropenia (n = 11, 17%), haemolytic anaemia (n = 10, 16%), cytokine release syndrome with haemophagocytic syndrome (n = 7, 11%) and other Haem-irAEs including bicytopenia or pure red cell aplasia (n = 5, 8%). Haem-irAEs are generally highly severe adverse reactions with a mortality rate of Haem-irAEs reported to be 14% (9 deaths among the 63 cases reported). The more severe and life-threatening Haem-irAEs were both cytokine release syndrome with haemophagocytic syndrome and pancytopenia or aplastic anaemia. Haem-irAEs induced by ICIs are potentially life-threatening. By discussing their pathophysiological aspects and clinical picture, we propose in this review clinical guidelines for management.

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.

AIHA and Pancytopenia as Complications of Pembrolizumab Therapy for Metastatic Melanoma: A Case Report

Immunotherapy has been an emerging treatment for metastatic melanoma and several other malignancies since 2015. Hematological immune-mediated adverse effects from immunotherapy are rarely reported but they can cause serious harm to patients. Antibodies such as ipilimumab, nivolumab and pembrolizumab target different immune checkpoints to promote T cell anti-tumour response. In particular, pembrolizumab is an antibody that inhibits programmed cell death receptor 1 (PD-1) to upregulate tumour suppression. In this report, we present a case of pembrolizumab-induced autoimmune hemolytic anemia and pancytopenia in a patient who was receiving pembrolizumab treatment for metastatic melanoma. This patient has a history of chronic lymphocytic leukemia and was diagnosed with metastatic melanoma in 2017. He developed symptomatic AIHA and pancytopenia after receiving 8 cycles of pembrolizumab in 2018. Pembrolizumab treatment was discontinued and he was treated with blood transfusion and prednisone. After 5 months of tapering prednisone treatment, his anemia and pancytopenia have improved toward successful recovery. Cancer patients already face an increased risk of immunosuppression with conventional chemotherapy. This case report also summarized all reported cases of PD-1 inhibitor hematological adverse effects in the treatment of oncological diseases. These incidents reflect the risk of immune-mediated hematologic adverse effects, which should be considered in all patients using immunotherapy.

Clinical and laboratory features of autoimmune hemolytic anemia associated with immune checkpoint inhibitors

Immune checkpoint inhibitors (ICPis) are a novel class of immunotherapeutic agents that have revolutionized the treatment of cancer; however, these drugs can also cause a unique spectrum of autoimmune toxicity. Autoimmune hemolytic anemia (AIHA) is a rare, but often severe, complication of ICPis. We identified 14 patients from nine institutions across the United States who developed ICPi-AIHA. The median interval from ICPi initiation to development of AIHA was 55 days (interquartile range [IQR], 22-110 days). Results from the direct antiglobulin test (DAT) were available for 13 of 14 patients: 8 patients (62%) had a positive DAT and 5 (38%) had a negative DAT. The median pretreatment and nadir hemoglobin concentrations were 11.8 g/dL (IQR, 10.2-12.9 g/dL) and 6.3 g/dL (IQR, 6.1-8.0 g/dL), respectively. Four patients (29%) had a preexisting lymphoproliferative disorder, and two (14%) had a positive DAT prior to initiation of ICPi therapy. All patients were treated with glucocorticoids, with three requiring additional immunosuppressive therapy. Complete and partial recoveries of hemoglobin were achieved in 12 (86%) and 2 (14%) patients, respectively. Seven patients (50%) were rechallenged with ICPis, and one (14%) developed recurrent AIHA. Clinical and laboratory features of ICPi-AIHA were similar in DAT positive and negative patients. ICPi-AIHA shares many clinical features with primary AIHA; however, a unique aspect of ICPi-AIHA is a high incidence of DAT negativity. Glucocorticoids are an effective first-line treatment in the majority of patients with ICPi-AIHA, and most patients who are rechallenged with an ICPi do not appear to develop recurrence of AIHA.

Hematologic Complications of Immune Checkpoint Inhibitors

Immune checkpoint inhibitors have improved outcomes for patients with numerous hematological and solid cancers. Hematologic toxicities have been described, but the spectrum, timing, and clinical presentation of these complications are not well understood. We used the World Health Organization's pharmacovigilance database of individual-case-safety-reports (ICSRs) of adverse drug reactions, VigiBase, to identify cases of hematologic toxicities complicating immune checkpoint inhibitor therapy. We identified 168 ICSRs of immune thrombocytopenic purpura (ITP), hemolytic anemia (HA), hemophagocytic lymphohistiocytosis, aplastic anemia, and pure red cell aplasia in 164 ICSRs. ITP (n = 68) and HA (n = 57) were the most common of these toxicities and occurred concomitantly in four patients. These events occurred early on treatment (median 40 days) and were associated with fatal outcome in 12% of cases. Ipilimumab-based therapy (monotherapy or combination with anti-programmed death-1 [PD-1]) was associated with earlier onset (median 23 vs. 47.5 days, p = .006) than anti-PD-1/programmed death ligand-1 monotherapy. Reporting of hematologic toxicities has increased over the past 2 years (98 cases between January 2017 and March 2018 vs. 70 cases before 2017), possibly because of increased use of checkpoint inhibitors and improved recognition of toxicities. Future studies should evaluate incidence of hematologic toxicities, elucidate risk factors, and determine the most effective treatment algorithms. KEY POINTS: Immune-mediated hematologic toxicities are a potential side effect of immune checkpoint inhibitors (ICIs).Providers should monitor complete blood counts during treatment with ICIs.Corticosteroids are the mainstay of treatment for immune-mediated hematologic toxicities.Further research is needed to define patient-specific risk factors and optimal management strategies for hematologic toxicities.

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.

Nivolumab-induced cold agglutinin syndrome successfully treated with rituximab

Cold agglutinin syndrome is one of the rare immune-related adverse events of nivolumab. Rituximab should be considered for treatment of nivolumab-induced cold agglutinin syndrome.

Bicytopenia in Primary Lung Melanoma Treated with Nivolumab

A 73-year-old man who was a current smoker complained of weakness in his limbs and slow movement and was diagnosed with primary lung melanoma with brain metastases. Following stereotactic brain radiotherapy, nivolumab was administrated. After the first cycle of nivolumab, his blood neutrophil count and hemoglobin levels started to decline. Excluding other possible causes, nivolumab was considered the most probable cause of bicytopenia. Nivolumab was not restarted, and the bicytopenia gradually recovered with no corticosteroid administration for this event. While serious hematological adverse events regarding immune checkpoint inhibitors have been assumed to be rare, severe neutropenia and anemia should be considered in patients receiving immune checkpoint therapy.

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.

Haematological immune-related adverse events induced by anti-PD-1 or anti-PD-L1 immunotherapy: a descriptive observational study

BACKGROUND

Anti-programmed cell death 1 (PD-1) and anti-programmed cell death ligand 1 (PD-L1) antibodies are novel immunotherapies for cancer that can induce immune-related adverse events (irAEs). These adverse events can involve all organs, including the haemopoietic system. Thus far, haematological irAEs (haem-irAEs) have not been extensively characterised. This study aims to provide a comprehensive report of the haem-irAEs induced by anti-PD-1 or anti-PD-L1.

METHODS

In this descriptive observational study, we included consecutive patients aged at least 18 years with grade 2 or worse haem-irAEs induced by anti-PD-1 or anti-PD-L1 immunotherapy registered in three French pharmacovigilance databases: the Registre des Effets Indésirables Sévères des Anticorps Monoclonaux Immunomodulateurs en Cancérologie (REISAMIC; a prospective registry of patients treated with anti-PD-1 or anti-PD-L1 at a single centre), the ImmunoTOX committee of Gustave Roussy (a national referral database of suspected irAEs in patients treated with immunotherapy), and the registry of the Centre de Référence des Cytopénies Auto-Immunes de l'Adulte (CeReCAI; a national database of autoimmune cytopenias). Cases were reviewed by a central committee; adverse events had to be classed as certainly or probably related to anti-PD-1 or anti-PD-L1 therapy, and their severity was assessed according to the Common Terminology Criteria for Adverse Events (version 4.03). The primary endpoint was clinical description of haem-irAEs, as reported in all databases, and their frequency, as reported in the prospective REISAMIC registry.

FINDINGS

We screened 948 patients registered in the three databases from June 27, 2014, to June 29, 2018 (745 from REISAMIC, 190 from the ImmunoTOX committee, and 13 from CeReCAI). 35 patients (21 men and 14 women) with haem-irAEs related to anti-PD-1 or anti-PD-L1 were included in the study. Of 745 patients in the REISAMIC registry treated with anti-PD-1 or anti-PD-L1, four had haem-irAEs, giving a frequency of 0·5%. Median age in the 35 patients was 65 years (IQR 51-75), and the most common tumour types were melanoma (15 [43%] patients), non-small-cell lung cancer (12 [34%] patients), and lymphoma (four [11%] patients). 20 (57%) patients received nivolumab, 14 (40%) received pembrolizumab, and one (3%) received atezolizumab. Among the 35 patients, neutropenia, autoimmune haemolytic anaemia, and immune thrombocytopenia were the most common types of haem-irAE (each in nine patients [26%]), followed by pancytopenia or aplastic anaemia (five patients [14%]), bicytopenia (one patients with thrombocytopenia plus anaemia and one patient with neutropenia plus anaemia [6%]), and pure red cell aplasia (one patient [3%]). The maximum grade of severity was grade 2 in three (9%) patients, grade 3 in five (14%) patients, and grade 4 in 25 (71%) patients; two (6%) patients died from febrile neutropenia during haem-irAE related to anti-PD-1. Haem-irAEs resolved in 21 (60%) of the 35 patients.

INTERPRETATION

Haem-irAEs induced by PD-1 or PD-L1 inhibitors are rare but potentially life-threatening events. The most common clinical presentations are neutropenia, autoimmune haemolytic anaemia, immune thrombocytopenia, and aplastic anaemia. Investigations into earlier detection and better management are warranted.

FUNDING

Gustave Roussy and Gustave Roussy Immunotherapy Program.

Severe hemophagocytic lymphohistiocytosis in a melanoma patient treated with ipilimumab + nivolumab

BACKGROUND

Treatment of metastatic melanoma patients with immune checkpoint inhibitors is an important standard of care. Side effects are due to immune activation, can affect virtually all organ systems, and are occasionally severe. Although hematologic toxicity has been reported, we present a case of hemophagocytic lymphohistiocytosis (HLH) due to immune checkpoint inhibitor therapy.

CASE PRESENTATION

A patient with metastatic melanoma was treated with one course of ipilimumab + nivolumab and presented 3 weeks later with severe anemia and hyperferritinemia. A bone marrow biopsy revealed necrotic tumor cells, infiltrating T cells, and hemophagocytosis. The patient was treated with high-dose steroids; 12 months later, the patient remains off all therapy and in complete remission of both HLH and metastatic melanoma.

CONCLUSIONS

The hemophagocytic syndromes are attributable to dysregulated immune activation and share pathophysiologic mechanisms with immune activation from checkpoint inhibitors. Increasing use of regimens that include immune checkpoint inhibition require vigilant monitoring for immune-activating side effects as they can occasionally be life threatening, as in this case of HLH.

A case of pure red cell aplasia during nivolumab therapy for cardiac metastatic melanoma

Nivolumab is an antibody against programmed cell death 1 and functions as an immune checkpoint inhibitor for various malignancies, including unresectable melanomas. Nivolumab causes several immune-related adverse events, which typically include skin rash, pneumonitis, thyroid dysfunction, hepatitis, and colitis; in rare cases, anemia may be present. There are several reports of autoimmune hemolytic anemia that has developed in response to nivolumab; however, there are few reports of pure red cell aplasia (PRCA). We describe a patient who developed PRCA during nivolumab administration. A 70-year-old Japanese woman received nivolumab for cardiac metastasis from malignant melanoma from an unknown site. Twenty-one months after nivolumab administration (31 courses), treatment was discontinued because she developed severe anemia. Blood test results indicated normocytic, normochromic anemia, and reticulocytopenia, but all other components were normal. Bone marrow aspiration showed increased megakaryocytes and decreased erythroblasts; these findings were consistent with PRCA. Anemia improved without recurrence after treatment with corticosteroids and blood transfusions. The steroid dosage was reduced gradually, and to date, the patient has not experienced recurrence of anemia. The tumor decreased in size and the patient has shown a continued response to treatment with decrease in disease for 3 years. Although it is unclear how nivolumab causes PRCA, hematological toxicities have been reported in patients treated with immunotherapy drugs. PRCA might be an unrecognized immune-mediated adverse event that did not manifest during the clinical trial phase.

Pembrolizumab-Induced Pancytopenia: A Case Report

INTRODUCTION

Programmed death receptor-1 blockade with pembrolizumab is approved by the US Food and Drug Administration to treat patients with metastatic melanoma. Activating T cells to fight cancer may cause immune-mediated adverse events. Pembrolizumab-induced pancytopenia has not been previously reported in the medical literature, to our knowledge.

CASE PRESENTATION

A 52-year-old Caucasian woman with a diagnosis of metastatic melanoma of the rectum experienced multiple adverse events along her course of therapy with pembrolizumab, ranging from colitis, hepatitis, gastritis, and vitiligo after the fifth cycle of pembrolizumab; to knee synovitis after the 14th cycle; and to severe pancytopenia after the 18th cycle of pembrolizumab. Severe pancytopenia improved after high-dose corticosteroids and a 5-day course of intravenous immunoglobulin therapy.

DISCUSSION

In our case, pembrolizumab-induced Grade 4 pancytopenia resolved via a combination of corticosteroids and intravenous immunoglobulins. Pancytopenia reached a nadir in 10 weeks, and it took 16 weeks for meaningful recovery.

A case of autoimmune haemolytic anaemia after 39 cycles of nivolumab

With growing use of nivolumab, rare but serious side effects have surfaced in some patients. We present a case of autoimmune haemolytic anaemia that developed after 39 cycles of nivolumab. A 78-year-old man with metastatic lung adenocarcinoma, refractory to multiple lines of chemotherapy was switched to nivolumab. After around 2 years of stable course on nivolumab, he developed transfusion-dependent anaemia with haemoglobin of 8.6 g/dL. Nivolumab was held immediately. Bone marrow biopsy findings were inconclusive of myelodysplastic syndrome. Further testing was suggestive of haemolysis with haptoglobin <10 mg/dL, elevated reticulocyte count and identification of immunoglobulin G antibody. Haemoglobin improved significantly with initiation of 1 mg/kg prednisone in addition to rituximab weekly × four doses. The development of transfusion-dependent anaemia with the exposure to cytotoxic chemotherapy usually raises the question for myelodysplastic syndrome. In contradiction, our patient was diagnosed to have a haematological autoimmune complication related to immunotherapy.

Nivolumab in squamous cell carcinoma of the head and neck

INTRODUCTION

The prognosis of recurrent/metastatic (R/M) squamous cell carcinoma of the head and neck (HNSCC) after failure of first line chemotherapy is dismal. Until the publication of the results of CheckMate 141, not a single agent provided any survival benefit as a second line treatment for R/M HNSCC. Areas covered: A comprehensive review of the literature was conducted on the role of nivolumab in HNSCC. Expert commentary: Nivolumab is approved by the Food and Drug Administration for the treatment of patients based on the results of CheckMate 141 showing an overall survival benefit as compared to standard care (single agent docetaxel, methotrexate, or cetuximab). Of particular interest are immune-related adverse events which should be managed according to published guidelines.

Autoimmune haemolytic anaemia in a patient with advanced lung adenocarcinoma and chronic lymphocytic leukaemia receiving nivolumab and intravenous immunoglobulin

We describe a rare case of severe autoimmune haemolytic anaemia (AIHA) in the setting of underlying chronic lymphocytic leukaemia receiving intravenous immunoglobulin, history of warm IgG autoantibody and treatment with nivolumab for advanced non-small cell lung cancer. In this report, we describe AIHA as a potential serious immune-related adverse event from immune checkpoint inhibitors, discuss other potential contributing factors and review previously described cases of AIHA in patients receiving programmed death 1 (PD-1) inhibitors. In the era of immunotherapy, we hope to add literature to raise awareness of potential immune-related sequelae such as AIHA. We aim to highlight the importance of close monitoring for prompt identification and management of potentially fatal AIHA and immune-related adverse events of PD-1 inhibitors by holding immunotherapy and treating with high-dose steroids, particularly in subgroups which may be at increased risk.

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

Directed immunotherapy at the programmed cell death-1 receptor has demonstrated efficacy in non-small-cell lung cancer, metastatic melanoma, and various other malignancies. Immune checkpoint inhibitors are innovative therapies producing some impressive clinical responses with a more manageable adverse effect profile when compared to traditional chemotherapy. The more common adverse effects associated with these agents include fatigue, rash, myalgia, pyrexia, and cough, but less common yet serious adverse effects have included immune-mediated colitis, pneumonitis, hepatitis, type 1 diabetes, and encephalitis. Here we present a case of a female patient with glioblastoma multiforme, who was treated with the programmed cell death-1 receptor inhibitor nivolumab and subsequently developed aplastic anemia.

Prevalence of immune-related systemic adverse events in patients treated with anti-Programmed cell Death 1/anti-Programmed cell Death-Ligand 1 agents: A single-centre pharmacovigilance database analysis

AIM

The growing use of immune checkpoint inhibitors (ICIs) is associated with the occurrence of immune-related adverse events (irAEs). Few data are published on systemic, immunohaematological and rheumatic irAEs. In a pharmacovigilance database analysis, we screened for these irAEs and calculated their prevalence.

PATIENTS AND METHODS

Participants were recruited via Registre des Effets Indésirables Sévères des Anticorps Monoclonaux Immunomodulateurs en Cancérologie (REISAMIC)¹ a French registry of grade ≥2 irAEs occurring in ICI-treated patients. The pathologies of interest were systemic autoimmune and inflammatory diseases, rheumatic diseases and immune cytopenia.

RESULTS

Out of 908 patients treated with anti-Programmed cell Death 1 (PD1)/anti-Programmed cell Death-Ligand 1 (PD-L1) agents (together with an anti-cytotoxic T-lymphocyte antigen-4 (CTLA-4) agent in 40 cases) between December 2012 and December 2016 at a single centre, 21 patients experienced systemic irAEs. The types and the prevalence of irAEs were as follows: immune thrombocytopenia (0.2%), Sjögren syndrome (0.3%), rheumatoid arthritis (0.2%), polymyalgia rheumatica (0.2%), psoriatic arthritis (0.2%), seronegative polyarthritis (0.7%) and sarcoidosis (0.2%). Patients with Sjögren syndrome or seronegative polyarthritis were more likely to have received combination therapy with ipilimumab (2.5% for both). We described these 21 cases, together with nine additional cases from five other centres. Most irAE were moderately severe (grade 2, 63%). The median time to onset was 57°days (interquartile range (IQR) 24-117). The ICI was withdrawn in 12 cases, 25 patients (83%) received corticosteroids, and five patients (17%) received immunosuppressant/immunomodulatory agents. The irAEs resolved fully or partially in 28 cases (93%).

CONCLUSION

Although systemic, immunohaematological and rheumatic diseases are rarely associated with ICI use, the prevalence is higher when two ICIs are combined. Corticosteroids are often effective and may enable the continued administration of ICIs. Studies designed to identify at-risk patients are warranted.

Combined immune checkpoint blockade (anti-PD-1/anti-CTLA-4): Evaluation and management of adverse drug reactions

BACKGROUND

Combined immune checkpoint blockade (ICB) provides unprecedented efficacy gains in numerous cancer indications, with PD-1 inhibitor nivolumab plus CTLA-4 inhibitor ipilimumab in advanced melanoma as first-ever approved therapies for combined ICB. However, gains in efficacy must be balanced against a higher frequency and severity of adverse drug reactions (ADR). Because delays in diagnosis and management might result in symptom worsening and further complications, clinicians shall be well trained to identify ADR promptly and monitor patients adequately. This paper reviews safety data assessed by the European Medicines Agency for the anti-PD-1/CTLA-4 combination and provides a literature overview on published case reports for rare ADR with suspected potential underreporting. Incidences and kinetics of immune-related ADR are described. Recommendations for the evaluation and management of ADR are convened by an interdisciplinary expert panel focusing on rare but clinically important side effects arising from combined ICB. Pooled safety data from 1551 patients with advanced melanoma, treated either with 3mg/kg ipilimumab plus 1mg/kg nivolumab (N=407), or nivolumab alone (N=787), or ipilimumab alone (N=357) demonstrate that immune-related ADR occur more frequently for the combination, with a shorter time-to-onset, and tend to be more severe. The majority of events is reversible after systemic use of glucocorticoids, notably methylprednisolone or equivalents; in certain cases of long-lasting and refractory immune toxicities, non-steroidal immunosuppressants may be used, once ICB is interrupted or terminated. Combined ICB has considerable toxicities, therefore close monitoring and high experience in diagnosis and treatment of ADR is necessary.

Immunotherapy-associated autoimmune hemolytic anemia

BACKGROUND

Immunotherapy has been widely used in the treatment of several solid and hematologic malignancies. Checkpoint inhibitors have been the forefront of cancer immunotherapy in recent years. Cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed cell death 1 (PD-1) pathway are the prototypic checkpoint targets for immunotherapy. When combined, CTLA-4 and PD-1 checkpoint inhibitors work synergistically, but with increased probability of toxicity. The following case represents an unusual adverse effect of combined treatment with ipilimumab and nivolumab used for treatment of metastatic melanoma.

CASE PRESENTATION

A 43-year-old woman with metastatic melanoma presented with severe generalized weakness and fatigue. She has received two cycles of ipilimumab and nivolumab, last administered 3 weeks prior to her presentation. Initial investigations revealed severe anemia with appropriate reticulocytosis, severely elevated lactate dehydrogenase, undetectable haptoglobin level and positive direct coombs test. Patient was diagnosed with severe autoimmune hemolytic anemia secondary to ipilimumab and nivolumab. She was successfully treated with high dose steroids and rituximab.

CONCLUSIONS

In our case, we present a rare but serious adverse effect of immunotherapy. We illustrate the clinical presentation and management of immunotherapy associated autoimmune hemolytic anemia. Immunotherapy has revolutionized the treatment of many malignant conditions; therefore, it is imperative for health care professionals caring for cancer patient to be familiar with the adverse effects of immunotherapy, which allow for early recognition and management of these potentially lethal side effects.

Autoimmune Hemolytic Anemia as a Complication of Nivolumab Therapy

Recently, immunotherapeutic drugs, including PD-1 inhibitors (nivolumab, pembrolizumab), PD-L1 inhibitors (atezolizumab, avelumab), and CTLA4 inhibitors (ipiliumumab), have emerged as important additions to the armamentarium against certain malignancies and have been incorporated into therapeutic protocols for first-, second-, or third-line agents for these metastatic cancers. Immune checkpoint inhibitor nivolumab is currently FDA approved for the treatment of patients with metastatic malignant melanoma [Redman et al.: BMC Med 2016;14: 20], metastatic non-small cell lung cancer [Guibert and Mazières: Expert Opin Biol Ther 2015;15: 1789–1797], metastatic renal cell cancer [Farolfi et al.: Expert Opin Drug Metab Toxicol 2016;12: 1089–1096], and relapsed or refractory classic Hodgkin's lymphoma [Villasboas and Ansell: Expert Rev Anticancer Ther 2016;16: 5–12]. Given the current and increasing indications for these drugs, it is essential for all physicians to become well versed with their common adverse effects and to be observant for other less documented clinical conditions that could be unmasked with the use of such medications. A definite association between autoimmune hemolytic anemia and the immune checkpoint inhibitor nivolumab has not been clearly documented, although a few cases have been reported recently [Kong et al.: Melanoma Res 2016;26: 202–204; Schwab et al.: Case Rep Oncol 2016;9: 373–378; Tardy et al.: Hematol Oncol 2016, DOI: 10.1002/hon.2338]. We report a case of fatal autoimmune hemolytic anemia refractory to steroids in a patient treated with nivolumab for metastatic lung cancer, and reflect on the other reported cases of autoimmune hemolytic anemia after the use of nivolumab.