Sandrine Valade, MD, Saint-Louis University Hospital, Paris, France, discusses the prevalence of adverse events in CAR-T treated patients, and the challenges of distinguishing between them. She covers cytokine release syndrome (CRS), neutropenic fever, and macrophage activation syndrome (MAS) and hemophagocytic lymphohistiocytosis (HLH). This interview took place at the CAR-T Cell Therapy and the ICU meeting in London, UK, which was organized by EuroCARTForce.