RELAPSE OF ACUTE PROMYELOCYTIC LEUKEMIA FOLLOWS SERIAL NEGATIVE RT-PCR ASSAYS - A CAUTIONARY TALE

Six patients with acute promyelocytic leukaemia (APL) and t(15;17) wer e investigated by cytogenetics and by reverse transcriptase polymerase chain reaction (RT-PCR) for the fusion transcript PML-RARA. The clone was detected in remission following all-trans retinoic acid and chemo therapy by cytogenetics and/or by RT-PCR up to 2 months from diagnosis . Thereafter the PML-RARA transcript was not seen in 20/21 first remis sion samples in five cases studied. Remission was maintained in two pa tients, one following bone marrow transplantation (BMT). Despite seria l negative RT-PCR results, PML-RARA reemerged at or prior to relapse f ollowing BMT in the remaining three cases. Frequent molecular monitori ng and caution in the interpretation of negative RT-PCR results are in dicated in APL. Copyright (C) 1996 Elsevier Science Ltd