New rearrangement pattern after treatment of hairy-cell leukemia with 2-chlorodeoxyadenosine

Leukemic hairy cells are clonally proliferating B-lymphoid cells with clona l rearrangements of genes for immunoglobulin chains. We describe a patient with a new hairy-cell clone after treatment with 2-chlorodeoxyadenosine (2- CdA). In this patient, a single course of 2-CdA resulted in good partial re mission of hairy-cell leukemia, but Southern blot analysis of bone marrow b iopsies and polymerase chain reaction using seminested amplifications with consensus primers revealed a new rearranged band 4 months after therapy wit h 2-CdA. Four years after therapy, the patient is in complete clinical remi ssion and both bands disappeared during follow-up. The new rearranged band might have been related to prior treatment of hairy-cell leukemia with 2-Cd A. Copyright (C) 2000 S. Karger AG, Basel.