Haemophagocytic lymphohistiocytosis associated with immune checkpoint inhibitors: a descriptive case study and literature review

Clinical characterization of hemophagocytic lymphohistiocytosis caused by immune checkpoint inhibitors: a review of published cases

OBJECTIVE

An association exists between immune checkpoint inhibitors and hemophagocytic lymphohistiocytosis (HLH). Therefore, the main objective of this study was to collect data on this rare but potentially life-threatening immune-related adverse reaction to identify the medications that cause it, the clinical characteristics, and effective treatments.

METHODS

Literature in English and Chinese on immune checkpoint inhibitors causing HLH published from August 2014 to March 2024 was analyzed. Immune checkpoint inhibitors, immunotherapy, anti-PD-1, PD-L1 inhibitors, HLH, hemophagocytic lymphohistiocytosis, hemophagocytic syndrome keywords were used to find the literature on China Knowledge Network, Wanfang, PubMed and Emabase Databases.

RESULTS AND DISCUSSION

Twenty-four studies were included, with a total of 27 patients (18 males and 9 females) with a mean age of 58 years (range 26-86). The mean time to the onset of symptoms was 10.3 weeks (7 days-14 months). The main clinical characteristics were fever, cytopenia, splenomegaly, methemoglobinemia, hypofibrinogenemia, and bone marrow biopsy showed phagocytosis. Twenty-two patients improved after the treatment with steroids, cytokine blocking therapy and symptomatic treatment, four patients died, and one patient was not described.

CONCLUSION

HLH should be not underestimated as a potentially serious adverse effect of immune checkpoint inhibitors since appropriate treatments may save the life of patients.

A Case Report of Hemophagocytic Lymphohistiocytosis and Meningitis Due to Atezolizumab Treatment for Lung Adenocarcinoma

Immune checkpoint inhibitors (ICIs) are used to treat a variety of tumors. Despite their broad beneficial effects, these inhibitors can cause immune-related adverse events (irAEs) and even death. Hemophagocytic lymphohistiocytosis (HLH) and meningitis, although infrequent, can be aggressive and life-threatening due to excessive immune activation. Herein, we report a case of an 80-year-old man who developed HLH after receiving atezolizumab monotherapy as a second-line treatment for lung adenocarcinoma. He was treated for HLH with oral prednisolone (PSL), but further ataxia and dysuria developed, and a lumbar puncture diagnosed meningitis. Both HLH and meningitis improved with continued oral PSL treatment. This is the first case of atezolizumab-induced HLH with meningitis and highlights the importance of early diagnosis and treatment for rare irAE.

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.

Severe Cytokine Release Syndrome and Hemophagocytic Lymphohistiocytosis (HLH)-Like Syndrome Following Administration of Combined Brentuximab Vedotin and Nivolumab for Recurrent Classical Hodgkin Lymphoma: A Case Report

Brentuximab vedotin (BV) and nivolumab are increasingly utilized as a novel regimen in patients with relapsed/refractory classical Hodgkin lymphoma (cHL). A 26-year-old male presented to the hospital with refractory diabetic ketoacidosis and multiple electrolyte abnormalities, 9 days after the first dose of brentuximab vedotin and nivolumab for recurrent classical Hodgkin lymphoma. During his hospitalization, he developed multi-organ failure. His workup showed elevated cytokine levels concerning severe cytokine release syndrome (CRS) and hemophagocytic lymphohistiocytosis (HLH)-like syndrome. Despite treatment with CRS- and HLH-directed therapies, his clinical status deteriorated due to ongoing multifactorial shock and worsening multi-organ dysfunction, and comfort care measures were eventually pursued. To our knowledge, there have been no other cases reported of HLH-like syndrome after the combination of BV and nivolumab in patients with cHL. This case of a fatal adverse event following one dose of BV and nivolumab underscores the vital need for close monitoring of patients receiving this treatment regimen.

Hemophagocytic lymphohistiocytosis following pembrolizumab and bevacizumab combination therapy for cervical cancer: a case report and systematic review

BACKGROUND

Programmed cell death protein 1 (PD-1) checkpoint inhibitors such as pembrolizumab are novel therapeutics used to treat various advanced malignancies. Immune-related adverse events are common, among the most serious of these toxicities is hemophagocytic lymphohistiocytosis (HLH), which is a life-threatening disorder of unbridled immune activation but has not been properly established.

METHODS

We have procured the first case of hemophagocytic lymphohistiocytosis as an aftermath of treatment with pembrolizumab from the Sir Run Run Shaw Hospital, Zhejiang University, China. In a pursuit to enhance the understanding of this condition, a comprehensive systematic review was performed encompassing all reported instances of ICI-associated Hemophagocytic lymphohistiocytosis within the realms of PubMed and Embase databases.

RESULTS

We detail the recovery of a cervical cancer patient with a history of psoriasis who developed HLH after combined pembrolizumab and bevacizumab treatment. Remarkably, tumor lesions exhibited substantial and sustained regression. From an analysis of 52 identified Immune Checkpoint Inhibitor (ICI)-related HLH cases, we discovered that HLH often occurred within the first two treatment cycles and approximately 20% of these patients had a history of autoimmune-related diseases. Despite a 15% mortality rate, the majority of patients experienced positive outcomes. Notably, in instances of recovery from HLH, 80% showed positive tumor outcomes. Even after discontinuation of ICI treatment, tumor control persisted in some cases.

CONCLUSION

We identified the first case of HLH caused by ICI treatment in cervical cancer and summarized the possible occurrence factors of these cases, the treatment outcomes of HLH, and the impact on tumor outcomes.

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.

Checkpoint inhibitors

Immune checkpoint inhibitors are a class of antineoplastic therapies that unleash immune cells to kill malignant cells. These medications commonly cause immune-related adverse effects due to activated adaptive and innate immune cells, autoantibody production, and/or cytokine dysregulation. Hematologic toxicities are rare and of uncertain mechanism, and therefore management is often based on experiences with familiar conditions involving these perturbed immune responses. Management is challenging because one must attend to the hematologic toxicity while simultaneously attending to the malignancy, with the imperative that therapeutic effects be maintained or minimally interrupted when possible.

Clinical characteristics, treatment, and management of pembrolizumab induced hemophagocytic lymphohistiocytosis

BACKGROUND

Hemophagocytic lymphohistiocytosis (HLH) is a rare and fatal adverse reaction to pembrolizumab. The clinical characteristics of pembrolizumab induced HLH are unknown. Exploring the clinical features of pembrolizumab induced HLH is crucial for the treatment and prevention of immune checkpoint inhibitor-induced HLH.

METHODS

The literature related to pembrolizumab induced HLH was collected for retrospective analysis by searching the Chinese and English databases from inception until August 31, 2023.

RESULTS

A total of 24 patients were included, including 17 men (70.8%) with a median age of 61 years (41,80). The time between the last infusion and the start of HLH ranged from 2 to 46 days, with a median time of 14 days. Fever (100%) was the most common symptom, accompanied by splenomegaly (14 cases, 58.3%) and hepatomegaly (6 cases, 25.0%). Laboratory examination revealed revealed anemia (18 cases, 75.0%), leukopenia (12 cases, 50.0%), thrombocytopenia (20 cases, 83.3%), hypertriglyceridemia (11 cases, 45.8%), hypofibrinogenemia (11 cases, 45.8%). decreased natural killer cell function (7 cases, 29.2%), and elevated soluble CD25(15 cases, 62.5%). All patients developed hyperferriinemia, with a median of 30,808 ng/mL (range 1303 ~ 100,000). Bone marrow biopsy showed hemophagocytosis (15 cases, 62.5%). After discontinuation of pembrolizumab and treatment with steroids, etoposide, intravenous immunoglobulin, cytokine blocking, and immunosuppression, 17 patients recovered or improved, and 5 patients eventually died.

CONCLUSION

HLH should be suspected when unexplained fever, cytopenia, splenomegaly, and elevated aminotransferase occur in patients using pembrolizumab. Screening for risk factors before treatment with pembrolizumab may be necessary to prevent HLH.

Immune checkpoint inhibitor-associated hemophagocytic lymphohistiocytosis in a patient with chronic lymphocytic leukemia

Haemophagocytic lymphohistiocytosis (HLH) is a rare complication of immune checkpoint inhibitor therapy. A 55-year-old male with stable chronic lymphocytic leukemia presented with fevers and symptomatic anaemia after nine cycles of nivolumab for metastatic melanoma. Investigations were consistent with autoimmune haemolytic anemia and corticosteroids were initiated. Thrombocytopenia and elevated liver enzymes without evidence of chronic lymphocytic leukaemia transformation was present. Ferritin was elevated, and thus HLH was considered and subsequently confirmed on a bone marrow biopsy. Corticosteroid monotherapy was continued, with resolution of fevers and improvement in cytopenias and liver enzymes. A six month corticosteroid tapering regimen was initiated, and he remains in HLH remission. This case highlights the importance of prompt recognition of immune checkpoint inhibitor-related HLH in patients with concurrent haematological malignancy.

Diagnosis and Management of Adult Malignancy-Associated Hemophagocytic Lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is a syndrome of severe, dysregulated inflammation driven by the inability of T cells to clear an antigenic target. When associated with malignancy (mHLH), the HLH syndrome is typically associated with extremely poor survival. Here, we review the diagnosis of secondary HLH (sHLH) syndromes in adults, with emphasis on the appropriate workup and treatment of mHLH. At present, the management of HLH in adults, including most forms of mHLH, is based on the use of corticosteroids and etoposide following the HLH-94 regimen. In some cases, this therapeutic approach may be cohesively incorporated into malignancy-directed therapy, while in other cases, the decision about whether to treat HLH prior to initiating other therapies may be more complicated. Recent studies exploring the efficacy of other agents in HLH, in particular ruxolitinib, offer hope for better outcomes in the management of mHLH. Considerations for the management of lymphoma-associated mHLH, as well as other forms of mHLH and immunotherapy treatment-related HLH, are discussed.

Hemophagocytic Lymphohistiocytosis Associated with Immunological Checkpoint Inhibitors: A Pharmacovigilance Study

BACKGROUND

Acquired hemophagocytic lymphohistiocytosis (HLH) is a rare but potentially fatal condition characterized by hyperactivation of macrophages and cytotoxic lymphocytes, combining a series of non-specific clinical symptoms and laboratory disorders. Etiologies are multiple: infectious (mainly viral) but also oncologic, autoimmune or drug-induced. Immune checkpoint inhibitors (ICI) are recent anti-tumor agents associated with a novel profile of adverse events triggered by immune system over-activation. Here, we sought to provide a comprehensive description and analysis of HLH cases reported with ICI since 2014.

METHODS

Disproportionality analyses were performed in order to further explore the association between ICI therapy and HLH. We selected 190 cases, 177 from the World Health Organization pharmacovigilance database and 13 from the literature. Detailed clinical characteristics were retrieved from the literature and from the French pharmacovigilance database.

RESULTS

The cases of HLH reported with ICI concerned men in 65% of cases with a median age of 64 years. HLH occurred in an average of 102 days after the initiation of ICI treatment and mostly concerned nivolumab, pembrolizumab and nivolumab/ipilimumab combination. All cases were considered serious. Most cases presented a favorable outcome (58.4%); however, death was reported for 15.3% of patients. Disproportionality analyses showed that HLH was seven times more frequently reported with ICI therapy than with other drugs and three times more than with other antineoplastic agents.

CONCLUSIONS

Clinicians should be aware of the potential risk of ICI-related HLH to improve the early diagnosis of this rare immune-related adverse event.

Hemophagocytic lymphohistiocytosis as an etiology of bone marrow failure

Hemophagocytic lymphohistiocytosis (HLH) is a syndrome of multiorgan system dysfunction that is caused by hypercytokinemia and persistent activation of cytotoxic T lymphocytes and macrophages. A nearly ubiquitous finding and a diagnostic criterion of HLH is the presence of cytopenias in ≥ 2 cell lines. The mechanism of cytopenias in HLH is multifactorial but appears to be predominantly driven by suppression of hematopoiesis by pro-inflammatory cytokines and, to some extent, by consumptive hemophagocytosis. Recognition of cytopenias as a manifestation of HLH is an important consideration for patients with bone marrow failure of unclear etiology.

Treatment-related hemophagocytic lymphohistiocytosis due to atezolizumab: a case report and review of the literature

Background

Immune checkpoint inhibitors avoid inhibition of T-cell responses, upregulating antitumor immune response. Moreover, a dysregulation with hyperactive immune response can be caused, some of them underdiagnosed. Hemophagocytic lymphohistiocytosis is a rare and often fatal syndrome of uncontrolled and ineffective hyperinflammatory response that triggers an inflammatory cascade that can lead in many cases to death.

Case presentation

We report the case of a 67-year-old Caucasian man with stage IV lung adenocarcinoma who developed hemophagocytic lymphohistiocytosis after initiation of atezolizumab, an antagonist of programmed death-ligand 1. Even with early diagnosis and proper treatment, death occurs in approximately half of all cases reported.

Conclusion

Key markers are needed to better identify patients at risk of developing severe immune-related adverse events. In addition to key markers, a higher degree of suspicion and early intervention are needed to improve outcomes in acquired hemophagocytic lymphohistiocytosis, especially with the increasingly and expanding use of immune activation.

Malignancy-associated haemophagocytic lymphohistiocytosis

Haemophagocytic lymphohistiocytosis (HLH) is an inflammatory syndrome that can occur with cancer (malignancy-associated HLH) or with immune-activating therapies for cancer. Patients with lymphoma appear to be at particularly high risk for malignancy-associated HLH. The familial form of HLH is characterised by uncontrolled activation of macrophages and cytotoxic T cells, which can be identified by genetics or specific immune markers. However, the pathophysiology of malignancy-associated HLH is not well understood, and distinguishing pathological immune activation from the laboratory and clinical abnormalities seen in cancer and cancer treatment is challenging. Emerging diagnostic tools, such as serum cytokine or chemokine concentrations, flow cytometry, and other functional measures, are discussed. Mortality remains high with current approaches. Targeted therapy, including blockade of specific cytokines such as IL-1, IL-6, and IFNγ, and inhibition of the JAK-STAT pathways might improve outcomes for some patients. Finally, we discuss a framework for thinking of malignancy-associated HLH within a larger umbrella concept of cytokine storm syndrome.

Secondary hemophagocytic lymphohistiocytosis due to nivolumab/ipilimumab in a renal cell cancer patient-A case report

Secondary immune-related hemophagocytic lymphohistiocytosis is a rare but life-threatening complication of immune checkpoint inhibitors. HLH-2004 and HLH-1994 guidelines originally developed for primary HLH are the only available guidelines. It has proven to have a good prognosis if diagnosed promptly with discontinuation of immunotherapy and treated with corticosteroid monotherapy.

Hematologic complications of immune checkpoint inhibitors

Immune checkpoint inhibitors are a class of anti-neoplastic therapies that unleash immune cells to kill malignant cells. There are currently 7 medications FDA-approved for the treatment of 14 solid tumors and 2 hematological malignancies. These medications commonly cause immune-related adverse effects due to overactive T lymphocytes, autoantibody production, and/or cytokine dysregulation. Hematological toxicities are rare and of uncertain mechanism, and therefore management is often based on experiences with familiar conditions involving these perturbed immune responses, such as autoimmune hemolytic anemia, immune thrombocytopenia, and idiopathic aplastic anemia. Management is challenging because one must attend to the hematological toxicity while simultaneously attending to the malignancy, with the imperative that effective cancer therapy be maintained or minimally interrupted if possible. The purpose of this review is to assist clinicians by providing a clinical and pathophysiological framework in which to view these problems.

Encephalitis Associated With Hemophagocytic Lymphohistiocytosis Secondary to Immune Checkpoint Inhibitors: An Unfamiliar Spin-Off

Checkpoint inhibitors (CPI) have become mainstream in standard therapy in various tumors, especially in malignant melanoma. Despite their widespread beneficial effects, these inhibitors are also notorious for immune-related adverse events (irAEs). Hemophagocytic lymphohistiocytosis (HLH) is an aggressive and life-threatening syndrome of excessive immune activation. We report a case of a 33-year-old male having a history of metastatic melanoma on immunotherapy (status post two cycles of ipilimumab/nivolumab) admitted for persistent fever and elevated liver enzymes. Additional work showed anemia, thrombocytopenia, hypertriglyceridemia, and hyperferritinemia which meet the diagnostic criteria of histiocyte society HLH-2004. The patient was effectively treated with oral prednisone. Moreover, further complications encompassed slurred speech, word-finding difficulties, ataxia, and lower extremity hyperreflexia concerning for autoimmune encephalitis. He was treated with high-dose IV methylprednisolone (1 gram/day for 3 days) with improvement in symptoms. Autoimmune encephalitis associated with HLH can be fatal - high-dose IV methylprednisolone should be considered, but this avenue still needs to be explored.

Response to Treatment with an Anti-Interleukin-6 Receptor Antibody (Tocilizumab) in a Patient with Hemophagocytic Syndrome Secondary to Immune Checkpoint Inhibitors

Background. Immunotherapy represents one of the fundamental treatments in the management of some types of cancer, especially malignant melanoma. Toxicity derived from increased immune system activity can manifest in multiple organs and systems. We present a case of hematological toxicity, manifested as hemophagocytic syndrome (HPS), which was successfully treated with an anti-interleukin-6 antibody (tocilizumab). Case Report. This case presents a 75-year-old woman diagnosed with metastatic choroidal melanoma, refractory to several lines of treatment. After the failure of the previous lines, ipilimumab was started. After the third dose, she developed grade 2 thrombocytopenia and anemia accompanied by elevated levels of ferritin, triglycerides, and decreased fibrinogen. Hemophagocytosis was observed in the bone marrow biopsy, and a PET-CT showed splenomegaly with increased metabolism. Treatment was based on high doses of corticosteroids and tocilizumab. Four days after the start of treatment, progressive clinical and analytical improvement was observed, achieving total remission of the condition. Discussion. HPS induced by immunotherapy is due to an immunorelated cytokine storm syndrome (CSS). The administration of the anti-interleukin-6 receptor antibody drug acted on this cytokine cascade, leading to stabilization and subsequent remission. For this reason, the use of tocilizumab should be part of the immunotherapy-induced HPS treatment algorithm.