Prolonged Third Remission in a Patient With Acute Promyelocytic Leukemia After Consolidation Chemotherapy With Intermittent Intermediate Dose Ara-C and Maintenance With Intermittent all-trans Retinoic Acid (ATRA)

Abstract

The benefit of all-trans-retinoic acid (ATRA) in the front line therapy of acute promyelocytic leukemia (APL) is well established, but its role in postremission therapy and in the treatment of relapse is currently under investigation. Moreover, the impact of cytosine arabinoside (Ara-C) in the therapy of APL has been questioned in recent studies. We report a prolonged third molecular remission (MR) in a patient with hyperleukocytotic APL after induction with ATRA, consolidation chemotherapy (CT) with intermittent intermediate dose Ara-C and maintenance therapy with intermittent ATRA. While the first two remissions were relatively short (8 months and 11 months, resp.), the duration of the third continuous CR (49+ months) is more than twice as long as the length of the two previous remissions combined. In this case Ara-C followed by intermittent ATRA maintenance was a safe and effective therapy for relapsed disease. A third molecular remission of such duration and quality is unusual.

Key Words:

• APL
• t(15, 17)
• PML/RARα RT-PCR
• postremission therapy
• relapse therapy
• intermittent ATRA
• intermittent intermediate dose Ara-C