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)

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 pos tremission therapy and in the treatment of relapse is currently under inves tigation, Moreover, the impact of cytosine arabinoside (Ara-C) in the thera py of APL has been questioned in recent studies. We report a prolonged thir d molecular remission (MR) in a patient with hyperleukocytotic APL after in duction with ATRA, consolidation chemotherapy (CT) with intermittent interm ediate 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 a s 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 th erapy for relapsed disease. A third molecular remission of such duration an d quality is unusual.