Nivolumab-related severe thrombocytopenia in a patient with relapsed lung adenocarcinoma: a case report and review of the literature

Successful Treatment of Steroid-Refractory Immune Thrombocytopenia in a Patient Developing Multiple Myeloma While on Immune Checkpoint Inhibitor Therapy for Lung Cancer: A Case Report

Immune checkpoint inhibitor-related thrombocytopenia (irTCP) is a relatively rare immune-related adverse event (irAE); however, overall survival may worsen when it occurs. Prolonged use of high-dose steroids can diminish the effectiveness of immune checkpoint inhibitor (ICI) therapy on the primary disease because of T lymphocyte suppression, thus early tapering is necessary. We experienced a rare case of a 79-year-old male who concurrently developed irTCP and multiple myeloma (MM) during treatment with ICIs for lung adenocarcinoma. The patient exhibited severe thrombocytopenia and elevated serum IgA levels. Based on various tests, we diagnosed MM and irTCP. Despite administering the standard bortezomib plus dexamethasone (Bd therapy) treatment for MM, there was no response and the irTCP was steroid-resistant. Consequently, we administered a regimen including daratumumab (DPd therapy) for steroid-resistant irTCP and refractory MM, which resulted in a response. As a result, we were able to avoid prolonged use of high-dose steroids and the patient is stable without exacerbation of lung adenocarcinoma for 1 year and 5 months after the onset of MM. To our knowledge, there are no cases of MM developing during ICI treatment and this is the first case report in which daratumumab was effective for the treatment of irTCP.

Association of thrombocytopenia with immune checkpoint inhibitors: a large-scale pharmacovigilance analysis based on the data from FDA adverse event reporting system database

Introduction: An increasing number of immune-related adverse events (irAEs) induced by immune checkpoint inhibitors (ICIs) have been reported during clinical treatment. We aimed to explore the clinical characteristics of patients with ICIs-induced ITP under different therapeutic strategies based on the FAERS database and explore the potential biological mechanisms in combination with TCGA pan-cancer data. Methods: Data from FAERS were collected for ICIs adverse reactions between January 2012 and December 2022. Disproportionality analysis identified ICIs-induced ITP in the FAERS database using the reporting odds ratio (ROR), proportional reporting ratio (PRP), Bayesian confidence propagation neural network (BCPNN), and multi-item gamma Poisson shrinker algorithms (MGPS). The potential biological mechanisms underlying ITP induced by ICIs were examined using TCGA transcriptome data on cancers. Results: In the FAERS, 345 ICIs-induced ITP reports were retrieved, wherein 290 (84.06%) and 55 (15.94%) were reported as monotherapy and combination therapy, respectively. The median age of the reported patients with ICIs-induced ITP was 69 years (IQR 60-76), of which 62 (18%) died and 47 (13.6%) had a life-threatening outcome. The majority of reported indications were lung, skin, and bladder cancers, and the median time to ITP after dosing was 42 days (IQR 17-135), with 64 patients (43.5%) experiencing ITP within 30 days of dosing and 88 patients experiencing ITP in less than 2 months (59.9%). The occurrence of ICIs-induced ITP may be associated with ICIs-induced dysregulation of the mTORC1 signaling pathway and megakaryocyte dysfunction. Conclusion: There were significant reporting signals for ITP with nivolumab, pembrolizumab, cemiplimab, atezolizumab, avelumab, durvalumab, ipilimumab, nivolumab/ipilimumab, and pembrolizumab/ipilimumab. Patients treated with anti-PD-1 in combination with anti-CTLA-4 are more likely to have an increased risk of ICIs-induced ITP. Patients with melanoma are at a higher risk of developing ITP when treated with ICI and should be closely monitored for this risk within 60 days of treatment. The potential biological mechanism of ICIs-induced ITP may be related to the dysfunction of megakaryocyte autophagy through the overactivation of the mTOR-related signaling pathway. This study provides a comprehensive understanding of ICIs-induced ITP. Clinicians should pay attention to this potentially fatal adverse reaction.

PD-1/PD-L1 inhibitor-induced immune thrombocytopenia: A pharmacovigilance study and systematic review

INTRODUCTION

Programmed cell death-1 (PD-1) and programmed cell death ligand-1 (PD-L1) immune checkpoint inhibitors (ICIs) are used for a variety of cancers and are associated with a risk of developing immune-related adverse events, most commonly dermatitis, colitis, hepatitis, and pneumonitis. Immune-mediated hematologic toxicities have been reported, but are less well-described in the literature. Immune thrombocytopenia (ITP) is a rare autoimmune, hematologic adverse event that has been reported with PD-1/PD-L1 inhibitors.

METHODS

We performed a retrospective observational analysis of the United States Food and Drug Administration Adverse Event Reporting System (FAERS) data. We searched for cases of ITP reported with exposure to PD-1/PD-L1 inhibitors from initial FDA approval for each agent to September 30, 2022. Disproportionality signal analysis was done by calculating the reporting odds ratio (ROR). Oxaliplatin was used as a positive control for sensitivity analysis as it is an anticancer therapy that has been associated with drug-induced ITP. A systematic review of the PubMed database was also conducted to identify published cases of PD-1/PD-L1 inhibitor-induced ITP.

RESULTS

There were 329 reports of ITP with ICIs in the FAERS database that were reviewed for a disproportionality signal, including atezolizumab (n = 27), durvalumab (n = 17), nivolumab (n = 160), and pembrolizumab (n = 125). The ROR was significant for atezolizumab (ROR 5.39, 95 % CI 3.69-7.87), avelumab (ROR 10.32, 95 % CI 4.91-21.69), durvalumab (ROR 7.91, 95 % CI 4.91-12.75), nivolumab (ROR 9.76, 95 % CI 8.34-11.43), and pembrolizumab (ROR 12.6, 95 % CI 10.55-15.06). In our systematic review, we summated 57 cases of ICI-induced ITP. Nivolumab and pembrolizumab had the most reported cases of ITP in the literature. Most cases reported (53 %) included ITP-directed therapies beyond corticosteroids for the management of ICI-induced ITP.

CONCLUSION

There is a significant reporting signal of ITP with several ICI agents. Clinicians should be aware of and monitor for signs of this potentially serious adverse event.

Cerebral Infarction as a Rare Adverse Event of Immune Checkpoint Inhibitors in Patients With Head and Neck Squamous Cell Carcinoma: A Case Series

Immune checkpoint inhibitors (ICIs) are a novel treatment option for treating head and neck squamous cell carcinoma (HNSCC). Among the immune-related adverse effects, cerebral infarction (CI) is a rare but fatal complication, and it has been reported in various cancers, except HNSCC. Herein, we describe three cases of patients diagnosed with HNSCC who experienced CI following ICI treatment. In addition, we conducted a comprehensive literature review on ICI-related thrombosis. Three patients with recurrent HNSCC were treated with nivolumab. Two patients had a history of CI, or heart disease, and were concurrently prescribed antithrombotic medications during nivolumab treatment. The number of nivolumab administrations varied from 1-25 before the onset of CI. All patients experienced worsening of neurological symptoms due to CI, irrespective of antithrombotic treatment, and they ultimately succumbed to the disease within 16-222 days following their initial ICI administration. ICIs may cause thromboembolisms, leading to CI. Based on our review of the literature, a history of thromboembolism or heart disease could be a risk factor for ICI-related thrombosis.

[Immune Thrombocytopenia Induced by Sintilimab in Lung Cancer: A Case Report and Literature Review]

Immune checkpoint inhibitors (ICIs) show unique advantages in the treatment of lung cancer, making the treatment of lung cancer enter the era of immunotherapy, but ICIs will also have adverse reactions, and the incidence of immune-induced hematological toxicity is not very high. Immunotherapy-induced thrombocytopenia is a rare adverse event.We report one case of thrombocytopenia induced by ICIs and review the literature on thrombocytopenia associated with ICIs and discuss the clinical features, possible mechanisms, and optimal treatment. 
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Case Report: Life-threatening pancytopenia with tislelizumab followed by cerebral infarction in a patient with lung adenocarcinoma

Immune checkpoint inhibitors (ICIs) are an integral antitumor therapy for many malignancies. Most patients show very good tolerability to ICIs; however, serious immune-related adverse events (irAEs) with ICIs have been well documented and prevent some patients from continuing ICIs or even become the direct cause of patient death. Cytopenia is a rare irAE but can be life-threatening. Here, we present the case of a 66-year-old male patient with metastatic lung adenocarcinoma who received two doses of chemotherapy + PD-1 antibody tislelizumab and developed pancytopenia after each dose. Although the first episode of pancytopenia resolved with a treatment regimen of granulocyte colony-stimulating factor (G-CSF), thrombopoietin (TPO), and red blood cell and platelet transfusion, the second episode showed extreme resistance to these treatments and improved only after the administration of steroids. His second pancytopenia episode resolved after a long course of treatment with methylprednisolone, G-CSF, TPO, hetrombopag and multiple red blood cell and platelet transfusions. However, he suffered a cerebral infarction when his platelet count was in the normal range and gradually recovered 1 week later. This case highlights the importance of the early recognition and management of hematological irAEs.

Kutane Nebenwirkungen unter Immun-Checkpoint-Inhibitor-Therapie

Moderne Immuntherapeutika wie Nivolumab, Pembrolizumab oder Ipilimumab, die sogenannte Immun-Checkpoints blockieren, haben die onkologische Therapie in den letzten Jahren revolutioniert. Mit dem neuen Wirkmechanismus der Blockade wichtiger Kontrollpunkte im Immunsystem zeigen sich jedoch auch eine Vielzahl an unterschiedlichen Nebenwirkungen. Diese treten nicht selten an der Haut auf. Zu den häufigsten dermalen Reaktionen unter Immuntherapie zählen die Vitiligo, Exantheme, blasenbildende Reaktionen oder der Lichen planus. Ausgeprägter Juckreiz kann Patienten stark beeinträchtigen. Der Verlauf bei auf die Haut beschränkten Nebenwirkungen ist häufig mild und gut zu behandeln oder selbstlimitierend. Hauterscheinungen können jedoch auch als Symptom systemischer Reaktionen auftreten. Eine frühe Diagnosestellung, die Einleitung einer adäquaten Therapie sowie eine interdisziplinäre Betreuung bei komplexen Erkrankungen sind entscheidend, um dauerhafte Einschränkungen für die Patienten zu verhindern und eine sichere Behandlung der zugrundeliegenden Tumorerkrankung gewährleisten zu können.

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.

Immune Thrombocytopenia Induced by Immune Checkpoint Inhibitrs in Lung Cancer: Case Report and Literature Review

Immune checkpoint inhibitors (ICIs), including antibodies targeting programmed cell death protein-1 (PD-1) and programmed cell death ligand-1 (PD-L1), are being extensively used on advanced human malignancies therapy. The treatment with ICIs have acquired durable tumor inhibition and changed the treatment landscape in lung cancer. Immune-related adverse events including pneumonitis and thyroiditis have been well described, but less frequent events, such as ICIs-induced thrombocytopenia, are now emerging and may sometimes be severe or fatal. Since early detection and prompt intervention are crucial to prevent fatal consequences, it is of outmost importance that medical staff is aware of these potential toxicities and learn to recognize and treat them adequately. This review focuses on the epidemiology, clinical presentation, mechanisms, and clinical management of ICIs-induced thrombocytopenia in patients with lung cancer. We also present a patient with advanced lung adenocarcinoma who received the PD-L1 inhibitor atezolizumab and eventually developed severe thrombocytopenia. The case indirectly suggests that cytokine changes might contribute to immune dysregulation in ICIs-induced thrombocytopenia.

Immune-checkpoint inhibitor-associated diabetes compared to other diabetes types - A prospective, matched control study

BACKGROUND

To describe checkpoint inhibitor-induced diabetes mellitus (CPI-DM) and to compare with regular type 1 (T1DM), type 2 (T2DM), and medication-induced diabetes mellitus (MI-DM).

METHODS

We included 88 177 adult patients from the Diabetes Patient Follow-Up (DPV) registry with diabetes manifestation between 2011 and 2020. Inclusion criteria were T1DM, T2DM, MI-DM, or CPI-DM. Because of the heterogeneity between the groups, we matched patients by age, sex, and diabetes duration using propensity scores. Patient data were aggregated in the respective first documented treatment year.

RESULTS

The matched cohort consisted of 24 164 patients; T1DM: 29, T2DM: 24000, MI-DM: 120, CPI-DM: 15 patients. Median age at manifestation of CPI-DM patients was 63.6 (57.2-72.8) years (53.3% male). Body mass index in CPI-DM patients was significantly lower (26.8 [23.9-28.1] kg/m² ) compared with T2DM patients (29.8 [26.2-34.3] kg/m² , P = 0.02). At manifestation, HbA1c was significantly higher in CPI-DM compared with MI-DM, but there was no difference during follow-up. Diabetic ketoacidosis (DKA) was documented in six CPI-DM patients (T1DM: 0%, T2DM: 0.4%, MI-DM: 0.0%). Fourteen CPI-DM patients were treated with insulin, and three received additional oral antidiabetics. The most common therapy in T2DM was lifestyle modification (38.8%), insulin in MI-DM (52.5%). Concomitant autoimmune thyroid disease was present in four CPI-DM patients (T1DM: 0.0%, T2DM: 1.0%, MI-DM: 0.8%).

CONCLUSIONS

The data from this controlled study show that CPI-DM is characterized by a high prevalence of DKA, autoimmune comorbidity, and metabolic decompensation at onset. Structured diagnostic monitoring is warranted to prevent DKA and other acute endocrine complications in CPI-treated patients.

Immune checkpoint inhibitor-related thrombocytopenia: incidence, risk factors and effect on survival

INTRODUCTION

Immune checkpoint inhibitors (ICI) are associated with unique immune-related adverse events (irAEs). Immune-related thrombocytopenia (irTCP) is an understudied and poorly understood toxicity; little data are available regarding either risk of irTCP or the effect of irTCP on clinical outcomes of patients treated with ICI.

METHODS

We conducted a retrospective review of sequential cancer patients treated with ICI between 2011 and 2017 at our institution. All patients who received ICI alone or in combination with other systemic therapy in any line of treatment were included; those with thrombocytopenia ≥ grade 3 at baseline were excluded. We calculated the incidence of ≥ grade 3 irTCP and overall survival (OS). Patient factors associated with irTCP were assessed.

RESULTS

We identified 1,038 patients that met eligibility criteria. Overall, 89 (8.6%) patients developed grade ≥ 3 thrombocytopenia; eighteen were attributed to ICI (1.73% overall). Patients who developed grade ≥ 3 irTCP had worse overall survival compared to those whose thrombocytopenia was unrelated to ICI (4.17 vs. 10.8 month; HR. 1.94, 95% CI 1.13, 3.33; log-rank p = 0.0164). Patients with grade ≥ 3 irTCP also had worse survival compared to those without thrombocytopenia (4.17 vs. 13.31 months; HR 2.22, 95% CI 1.36, 3.62; log-rank p = 0.001). The incidence of irTCP appeared lowest among those treated with PD-1/L1 monotherapy (p = 0.059) and was not associated with cancer type, smoking status, age, gender, race, or line of therapy.

CONCLUSIONS

Unlike other irAEs, we found that irTCP was associated with worse overall survival. The incidence of irTCP appeared lowest among those treated with PD-1/L1 monotherapy.

Response to Immune Checkpoint Inhibitor Treatment in Advanced Cervical Cancer and Biomarker Study

Background: Checkpoint inhibitor immunotherapy or immuno-oncology (IO) treatment in refractory cervical cancer yielded an objective response rate (ORR) of 12% in tumors expressing the programmed cell death ligand-1 (PD-L1) in the KEYNOTE-158 phase II study. We hypothesized that the positive response might be associated with the level of PD-L1 expression and/or the tumor mutation burden (TMB). We also aimed to analyze if responses could be associated with platinum sensitivity. Methods: This is a retrospective study of all consecutive patients with cervical cancer who received pembrolizumab or nivolumab. Results: Ten patients were identified. Median age was 64.5 years old (range 48-80). The response rate was 70% and the median duration of response was 21.0 months (range 1.8-26.7) after 20.7 months of follow-up (range 2.0-31.0). The response rate was 80% in patients with PD-L1 combined positive score (CPS) ≥ 10, and 75% in patients with tumor mutation burden (TMB) ≥ 10 mut/Mb. The mean progression-free survival (PFS) for the entire cohort was 20.2 months (95% CI 12.0-28.5). Seven patients had treatment for >12 months (range 14.6-31.0). Five patients were platinum-sensitive and 5 patients were platinum-resistant at the time of immunotherapy, and the response rate was similar regardless of platinum sensitivity. Conclusions: The positive response to IO treatment in advanced cervical cancer in this study was higher than published, and a possible association with the level of PD-L1 expression and the TMB level was suggested. A PD-L1 CPS score ≥ 10 or TMB ≥ 10 may be biomarkers to correlate with response, which should be explored in large studies.

Delayed immune thrombocytopenia after discontinuation of nivolumab therapy: A case report and literature review

INTRODUCTION

Nivolumab, a programmed death-1(PD-1) inhibitor antibody, have demonstrated anti-tumor activity for multiple malignancies. Such immune checkpoint inhibitors induce novel and distinctive adverse effects, which are collectively named immune-related adverse events. Immune-related adverse events can theoretically occur at any part of the body, including the haemopoietic system. Most immune-related adverse events developed within 10 weeks of receiving immunotherapy. Thus far, there is no report of immune thrombocytopenia as an immune-related adverse event developed after discontinuation of immunotherapy.

CASE REPORT

We describe a 62-year-old male with metastatic non-small cell lung cancer developed immune thrombocytopenia nearly two months after discontinuation of nivolumab. When thrombocytopenia was detected, the patient was undergoing radiotherapy of supraclavicular lymph nodes. After complex diagnosis-by-exclusion process, nivolumab-induced immune thrombocytopenia was diagnosed.

MANAGEMENT AND OUTCOME

Intravenous immunoglobulins 20 g daily for 5 days, intravenous methylprednisolone 40 mg daily for 14 days followed by oral prednisone, intermittent platelet transfusion and oral thrombopoietin receptor (eltrombopag 25 mg daily) were administered. After 30 days, his platelet count had achieved a level of adequate hemostasis and continued to improvement during the tapering period.

DISCUSSION

Most immune-related developed 6 months of immunotherapy. Clinicians need to be aware of a clinical diagnostic complex, developing months to years after discontinuation of immunotherapy, which recently is termed delayed immune-related events. This case is the first report of immune checkpoint inhibitors-induced thrombocytopenia that developed nearly 2 months after discontinuation of treatment with nivolumab for metastatic NSCLC. In future clinical practice, patients who have received immune checkpoint inhibitors develop new or unexplained symptom, irrespective of interval post-immunotherapy, immune-related adverse events should be considered.

Acquired amegakaryocytic thrombocytopenia after durvalumab administration

Immune checkpoint inhibitors (ICIs), despite their ability to potentiate antitumor T-cell responses, may cause various immune-related adverse events. Most cases of thrombocytopenia induced by ICIs have revealed a pathophysiologic mechanism of immune thrombocytopenia with increased platelet destruction and preserved megakaryocytes. Acquired amegakaryocytic thrombocytopenic purpura (AATP) is an unusual disorder characterized by thrombocytopenia with markedly diminished bone marrow megakaryocytes in the presence of otherwise normal hematopoiesis. AATP caused by ICIs has not been reported on. Herein, we present the case of a 79-year-old man diagnosed with squamous cell carcinoma of the lung who developed AATP after two courses of durvalumab, a drug targeting programmed death-ligand 1. Two weeks after the second cycle, his platelet count decreased to 2.1 × 10⁴/μL. After the patient underwent platelet transfusion, his platelet count increased to 8.1 × 10⁴/μL the next day but subsequently decreased repeatedly even after the ICI was discontinued. Six weeks after the second cycle, he developed interstitial pneumonia and was administered prednisolone (50 mg/day). However, thrombocytopenia did not improve. Bone marrow biopsy showed scarce megakaryocytes (< 1 megakaryocyte/10 high-power fields) with preservation of myeloid and erythroid series. Myelodysplasia, myelofibrosis, or metastatic lesions were not observed. Cytogenetic analysis showed a normal male karyotype of 46XY. Hence, the patient received eltrombopag, a thrombopoietin receptor agonist, and his platelet count subsequently improved. After recovery, bone marrow aspiration revealed a normal number of megakaryocytes. AATP is rarely the type of thrombocytopenia induced by ICIs and may be successfully treated with thrombopoietin receptor agonists.

Immune Thrombocytopenia Induced by Immune Checkpoint Inhibitors in Solid Cancer: Case Report and Literature Review

Immune checkpoint inhibitors, including antibodies targeting programmed cell death protein-1 (PD-1) and its receptor programmed cell death ligand-1 (PD-L1), represent promising therapeutic strategies for advanced human malignancies. However, a subgroup of patients experiences various autoimmune toxicities, termed immune-related adverse events (irAEs), that occur as a result of on-target and off-tumor autoimmune responses. Although irAEs are generally confirmed to be less severe than toxicities caused by conventional chemotherapy and targeted therapy, uncommon irAEs, such as immune thrombocytopenia, may occur with a very low incidence and sometimes be severe or fatal. This review focuses on the epidemiology, clinical presentation, and prognosis of immune thrombocytopenia occurring in advanced cancer patients induced by immune checkpoint inhibitors, especially in those with PD-1 or PD-L1 inhibitor treatment. We also first present one patient with non-small cell lung cancer who received the PD-L1 inhibitor durvalumab and developed severe thrombocytopenia.

Rare case of life-threatening thrombocytopenia occurring after radiotherapy in a patient treated with immune checkpoint inhibitor

Immune checkpoint inhibitors (ICIs) improve significantly outcome of patients with advanced renal cancer. Although immune-related adverse events involve frequently skin, digestive tract, lung, liver and endocrine organs, haematological toxicities are rare. We describe the case of a patient with metastatic renal cancer who was treated with nivolumab. Eight courses of nivolumab were administered without any toxicity; brain metastases were then diagnosed and treated with stereotactic radiotherapy. As the extra-cranial disease was stable, the ninth course of nivolumab was administered 5 days after the end of radiotherapy. One week later, he presented with rectal and nasal bleeding in a context of severe thrombocytopenia (1000/mm³). High dose of steroids and intravenous immunoglobulin reversed slowly the thrombocytopenia. This case highlights the possibility of life-threatening thrombocytopenia with ICIs. Interestingly, the close time relation with radiotherapy highlights a potential interaction, warranting a close follow-up of patients in this situation.

Severe immune thrombocytopenia induced by a single dose of nivolumab in a patient with advanced non-small cell lung cancer

Nivolumab-induced immune thrombocytopenia (ITP) is a rare process with few reported cases. We present a 67-year-old man with advanced non-small cell lung cancer who was hospitalized with severe thrombocytopenia. Physical exam was notable for petechiae across his chest and extremities as well as bullae in his oral cavity. The patient initially received high-dose glucocorticoids and intravenous immuno - globulin, but did not respond to treatment. He was then started on weekly rituximab and after three doses, there was complete resolution of his thrombocytopenia. Altogether, his presentation was an extreme case and rare side effect of immune checkpoint therapy, known as nivolumab-induced ITP. Diagnosis of nivolumab-induced ITP is challenging given the lack of specific testing and a wide differential diagnosis. There are few cases reporting severe ITP following nivolumab treatment. We highlight the importance of recognizing and treating this rare complication of immunotherapy.

Nivolumab-induced immune thrombocytopenia in a patient with malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is a rare and highly aggressive tumor. Nivolumab showed durable antitumor effect in patients with recurrent MPM and was approved for those patients in Japan in 2018. Immune related adverse event (irAE) is occurred in various organs and is suggestive to be related to better outcome of nivolumab. Frequency of hematological irAE is low and there are few reports about hematological irAE and association between irAE and outcome of nivolumab in patients with MPM. We present a case of recurrent MPM who responded to nivolumab treatment and experienced nivolumab-induced immune thrombocytopenia (ITP). Although high dose dexamethasone was administered and platelet count increased transiently, re-administration of dexamethasone was required to maintain normal count of platelet. The careful and intensive management of ITP treatment is necessary in cases who show no response or relapse to initial glucocorticoids treatment. This is the first report about nivolumab-induced ITP and association with response to nivolumab in MPM.

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Frequency of hematological immune related adverse event (irAE) is low and there are only a few reports of hematological irAE in patients with MPM.

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This patient needed repeated administration of dexamethasone for nivolumab-induced immune thrombocytopenia (ITP) treatment.

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Careful and intensive management of ITP treatment is necessary in patients who show no response or who relapse after initial glucocorticoid treatment.

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A clinical response to nivolumab was observed in this patient.

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This is the first report of nivolumab-induced ITP and its association with response to nivolumab treatment in a patient with MPM.