Wishing on a CAR: Understanding the Scope of Intrinsic T-cell Deficits in Patients with Cancer.

Treatment with chimeric antigen receptor T cells has led to impressive and durable responses in adult and pediatric malignancies refractory to conventional therapy; however, only patients with a handful of cancers have responded thus far and significant disparities exist between the response rates of pediatric and adult patients. A new extensive analysis of pediatric patient T-cell subsets at diagnosis and throughout the patients' chemotherapy courses in a variety of solid and hematologic malignancies sheds new light on the intrinsic T-cell deficits that may be partly to blame.See related article by Das et al., p. 492. ©2019 American Association for Cancer Research.