Pembrolizumab-related autoimmune hemolytic anemia in a patient with metastatic lung adenocarcinoma: a case report

Immune checkpoint inhibitors (ICIs) have become the main drugs for programmed cell death receptor-1 or ligand-1 expressing non-small cell lung cancer (NSCLC) combined with conventional chemotherapy. ICIs are generally more tolerable than cytotoxic chemotherapies in terms of toxicity, and ICI-related adverse events are mild and manageable. However, these drugs may lead to unexpected severe adverse events such as immune-related hematologic toxicities, which could be life-threatening. Here, a rare case of a pembrolizumab-related adverse event in a patient with NSCLC who showed early-onset hemolytic anemia and recovered by high-dose steroid and a series of plasma exchanges is reported.