Prolonged haematologic toxicity in CAR-T-cell therapy: A review

Chimeric antigen receptor-T-cell (CAR-T-cell) therapy is a novel immunotherapy with encouraging results for treatment of relapsed/refractory haematologic malignancies. With increasing use, our understanding of immune-mediated side effects such as cytokine release syndrome and neurotoxicity has improved; nevertheless, prolonged haematologic toxicity (PHT), with a high incidence rate, remains underrecognized. Owing to heterogeneity in populations, the CAR-T cells used and diseases treated as well as differences in the definition of PHT, its rate, risk factors and management vary across studies. In this review, we provide a narrative of PHT occurring in patients following CAR-T-cell therapy; evidence of PHT treatment strategies is also presented, with the aim of contributing to systematic understanding of PHT.