Predictive factors of bleeding and thrombosis during induction therapy in acute promyelocytic leukemia-a single center experience in 34 patients

In this retrospective study, the hemorrhagic and thrombotic events are reported at presentation and during induction in 34 consecutive acute promyelocytic leukemia (APL) patients treated in a single referral center. The most consistent hemostatic abnormality was decreased fibrinogen level (<150 mg/dL) found in 21 patients (61%), partial thromboplastin time (PTT) was normal almost in all patients. A mildly prolonged prothrombin time (PT) was observed in 14 patients (44%). Median platelet count was 30·109/L (range 3-191·109/L). Life-threatening bleeding manifestations occurred in 10 patients (29%). By multivariate analysis, severe bleeding complications did not correlate with hemostatic parameters but did correlate with white cell count at presentation. Four patients (12%) had severe thrombotic events, two cerebral sagital sinus thrombosis, one pulmonary embolism, and one subclavian vein thrombosis. Two other patients had pseudotumor cerebri. Three out of six patients with thrombotic events were found to have thrombophilia. These results may suggest an association between thrombophilia and thrombosis in APL patients. Two patients suffered from combined severe bleeding and thrombosis. Hemostatic parameters are not helpful in predicting neither hemorrhage nor thrombosis.