[A neoplasm of lymphoblasts committed to the B-cell lineage, typically composed of small to medium-sized blast cells. When the neoplasm involves predominantly the bone marrow and the peripheral blood, it is called precursor B lymphoblastic leukemia (B-cell acute lymphoblastic leukemia). When it involves nodal or extranodal sites, it is called B lymphoblastic lymphoma. (WHO, 2001) — 2003 ( NCI )]
UMLS (NCI) C0862030Precursor B-Lymphoblastic Lymphoma/Leukemia