precursor T-lymphoblastic leukemia
(pree-KER-ser T-LIM-foh-BLAS-tik loo-KEE-mee-uh)
An aggressive (fast-growing) type of leukemia (blood cancer) in which too many T-cell lymphoblasts (immature white blood cells) are found in the bone marrow and blood. Also called T-cell acute lymphoblastic leukemia and T-cell acute lymphocytic leukemia.