B-cell acute lymphoblastic leukemia with L1 morphology and coexistence of t(1;19) and t(14;18) chromosome translocations.

We report a case of adult de novo acute lymphoblastic leukemia (ALL) with unique cytogenetic abnormalities and discrepant morphologic and immunologic features. Morphology was L1 by the French-American-British classification, but flow cytometry was consistent with a mature B-cell phenotype. Cytogenetic analysis showed numerous chromosome abnormalities nonspecific for lymphoid neoplasm except for t(1;19) and t(14;18). The former is characteristic of pre-B-ALL and the latter is characteristic of follicular lymphoma. This is the first report of these two translocations occurring concurrently in ALL.