An unusual case of leukemic non-Hodgkin's lymphoma with blastic transformation

We report on a patient who was diagnosed as having B-cell chronic lymphocytic leukemia (CLL) with atypical morphology. Flow cytometry disclosed CD5, CD19, and CD23 positivity, an immunophenotype seen mostly in B-CLL. Histology of the spleen and bone marrow suggested a diagnosis of small lymphocytic lymphoma. Upon blastic transformation, only 3 years after the diagnosis had been made, unusual clinical and laboratory features emerged. Lymphoid blasts appeared in the peripheral blood, and the patient developed nodular infiltrates consisting of these blasts at recent venous puncture sites. The patient did not respond to chemotherapy and died. The lymphoid blasts in the peripheral blood were CD5-, CD19+, and CD23+ and harbored t(11;14) (q13;q32) and t(11;21)(p11;q21) translocations. To account for the possibility of two independent lymphoid malignancies, molecular genetic analyses were performed on samples from the spleen, bone marrow and a lymph node with the large-cell lymphoma, which showed identical clones in these tissues. This unusual case supports the idea that in leukemic non-Hodgkin's lymphoma, in addition to morphology, an accurate diagnostic workup requires immunophenotypic, cytogenetic, and molecular studies.