Pembrolizumab-Induced Pancytopenia: A Case Report

Abstract

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.

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

“…Anemia, neutropenia, thrombocytopenia, leukopenia and lymphopenia are reported to occur in 1%-10%, with febrile neutropenia and eosinophilia occurring in <1%. 2,3 However, few reports have described pancytopenia as an irAE. The mechanisms by which pembrolizumab induces pancytopenia are unknown.…”

New drugs and new toxicities: pembrolizumab-induced myocarditis

“…Significant inflammatory or immune-mediated reactions included infusion-related reactions (3.0%), hypothyroidism (6.9%) and pneumonitis (3.6%) 4. Furthermore, newer reports described notable toxicities, such as type 1 diabetes mellitus,5 pancytopenia,6 colitis,7 keratoacanthomas,8 scleroderma,9 myasthenia gravis10 and uveitis 11. In terms of cardiotoxicity, two case reports are available in the published literature.…”

Posttransfusion purpura with antibodies against human platelet antigen‐4a following checkpoint inhibitor therapy: a case report and review of the literature

“…Ipilimumab and nivolumab are two checkpoint inhibitors that bind to CTLA‐4 and PD‐L1, respectively, and thereby reactivate cytotoxic T cells to destroy cancer cells. Both agents have been associated with immune‐related cytopenias, including red cell aplasia, autoimmune neutropenia, and thrombocytopenia . One case series of 11 patients showed that the incidence of immune thrombocytopenia purpura (ITP) with checkpoint inhibitors in melanoma patients was less than 1% and that the majority of cases had spontaneous resolution of thrombocytopenia .…”