[Rare cause of pure white cell aplasia (PWCA) in a 76-year-old male patient].

Pure white cell aplasia (PWCA) is a rare hematological condition characterized by the complete absence of granulocytes and myeloid precursor cells in the bone marrow. In this case report, we describe a 76-year-old patient with chronic lymphocytic leukemia (CLL) and cutaneous squamous cell carcinoma of the right upper eyelid who developed PWCA after treatment with the immune checkpoint inhibitor (ICI) cemiplimab. The PWCA is a rare side effect of checkpoint inhibitors. The exact cause is not fully understood, but it is believed that dysregulation of the immune system triggers the condition. The treatment of PWCA typically involves corticosteroids and granulocyte colony-stimulating factors (G-CSF). In cases of non-response, high-dose intravenous immunoglobulin (IVIg) or cyclosporine can be administered.