Thrombotic events in acute promyelocytic leukemia

Abstract Introduction Thrombotic events (TE) appear to be more common in acute promyelocytic leukemia (APL) than in other acute leukemias, with reported prevalence ranging from 2 to10-15%. Materials and Methods We retrospectively analyzed the data on TE appearance in 63 APL patients. Results TE occured in 13 (20.6%) cases, four arterial (6.3%) and nine venous (14.3%). TE were more frequently diagnosed after initiation of weekly D-dimer monitoring (7 TE during 20 months vs 6 during 76 months, P = 0.032 ). Patients with and without venous thrombosis were significantly different regarding female/male ratio ( P = 0.046 ), PT ( P = 0.022 ), aPTT ( P = 0.044 ), ISTH DIC score ( P = 0.001 ), bcr3 ( P = 0.02 ) and FLT3-ITD ( P = 0.028 ) mutation. The most significant risk factor for venous TE occurrence in multivariate analysis was FLT3-ITD mutation ( P = 0.034 ). PAI-1 4G/4G polymorphism was five times more frequent in patients with venous TE than without it ( P = 0.05 ). Regarding risk factors for arterial TE we failed to identify any. Conclusions We have demonstrated that APL-related TE rate is higher than previously reported and that weekly D-dimer monitoring might help to identify patients with silent thrombosis. Moreover, our study suggests a possible relationship between venous TE occurrence and several laboratory findings (PT, aPTT, ISTH DIC score, bcr3 isoform, FLT3-ITD mutation and PAI 4G/4G). Prophylactic use of heparin might be considered in patients with ISTH DIC score  FLT3-ITD mutation and PAI 4G/4G.