CENTRAL-NERVOUS-SYSTEM RELAPSE IN ACUTE PROMYELOCYTIC LEUKEMIA IN PATIENTS TREATED WITH ALL-TRANS-RETINOIC ACID

All-trans retinoic acid (ATRA) is currently recommended as standard tr eatment for acute promyelocytic leukaemia (APL). However, there has be en increasing concern that ATRA is associated with unusual sites of re lapse. We present three cases of APL previously treated with ATRA who ultimately relapsed within the central nervous system (CNS) and hypoth esize that, by up-regulating intercellular adhesion molecules, ATRA ma y facilitate the passage of malignant promyelocytes across the blood-b rain barrier.