ABSTRACT
The phenotype of blasts is an independent prognostic parameter in B-ALL. B-lymphoblastic leukemia/lymphoma presents with primary involvement of lymph nodes, skin, bone, and other extranodal sites. Most cases do not express CD20 and occasional cases express BCL6, which differentiate B-ALL from Burkitt lymphoma. Characteristically, the expression of CD10 is bright, which distinguishes B-ALL from mature B-cell lympho mas of follicle center cell origin. Based on the immunophenotype, B-ALLs are divided into early pre-B-ALL (pro-B-ALL), common ALL (intermediate stage) and pre-B-ALL (most mature ALL). B-cell lymphomas of follicle center cell origin show bright expression of CD45, moderate to bright CD20, and moderate to bright expression of surface immunoglobulins (kappa or lambda). An analysis of disease-free survival rates for MRD + and MRD- patients shows that MRD positivity is associated with increased relapses (being most significant at 3-5 months post-induction and beyond).
