<unk>  (WHO 2008), previously labeled precursor<unk>  (WHO 2001) is a form of lymphoid leukemia and<unk>  in which too many T-cell lymphoblasts (immature white blood cells) are found in the blood, bone marrow, and tissues, particularly mediastinal lymph nodes. Labeling as leukemia or<unk>  depends on which feature is more pronounced in a given situation, but has no biological or treatment implication. It is uncommon in adults, but represents 15% of childhood acute<unk>  leukemia and 90% of<unk><unk> . The 2008 terminology dropped "precursor" to avoid linguistic redundancy because the lymphoblast is an immature precursor cell by definition.
T-lymphoblastic leukemia/lymphoma
Adult T-cell leukemia/lymphoma
T-cell acute lymphoblastic leukemia
B-cell prolymphocytic leukemia
T-cell prolymphocytic leukemia
Atypical chronic myeloid leukemia
Prolymphocytic leukemia
Minimally differentiated acute myeloblastic leukemia