CAR T cells targeting CD19 have been approved for patients with relapsed or refractory ALL, failing two or more prior protocols. Several institutional-based studies with other CAR T cells targeting CD19 have demonstrated outstanding response rates in patients with refractory disease, and the ability of CAR T cells to clear CNS leukemia. Nevertheless, these cases are sparse and have never been reported collectively.

Here, we aim to retrospectively assess toxicity and long term outcome of patients treated with CAR T cells for CNS relapse of ALL.

Inclusion Criteria:

• Prior diagnosis of B-cell acute lymphoblastic leukemia involving the central nervous system
• Treatment with CAR T cells (either on a clinical trial or commercial use) due to this indication

Retrospective review of patients with CNS - involvement of B-cell ALL, treated with CAR T cells targeting CD19 of either an institutional-based clinical trial, a pharma-based clinical trial or commercial product.