WT1 and acute lymphoblastic leukemia: The subsets were defined as follows: common-ALL: CALLA+, DR+, T (WT1/E/T11)-, smIg-, Tdt+; null-ALL: CALLA-, DR+, T (WT1/E/T11)-, smIg-, Tdt-; T-ALL: cALLA+/- DR+/- T (WT1/E/T11)+, smIg-, Tdt+; B-ALL: CALLA-, DR+, Tdt-.