PB1819: CHARACTERISTICS AND OUTCOME OF PATIENTS WITH ACUTE PROMYELOCYTIC LEUKEMIA IN SOUTHERN TUNISIA

Abstract

Background: All-trans retinoic acid (ATRA) is the major advance in the treatment of acute promyelocytic leukemia (APL). Its introduction in the treatment of APL has revolutionized the outcome of this disease. Aims: The current study reports the clinical features and treatment outcome of patients with acute promyelocytic leukemia (APL) treated at the hematology department of Sfax from Tunisia. Methods: Our study was retrospective. It concerned all patients with the diagnosis of APL and followed in the hematology department of Hedi Chaker Hospital Sfax, from January 2000 until December 2019. The diagnosis of APL is based on morphological, cytogenetic and molecular study. The specific treatment is similar to that of the French protocol APL93 until 2013, and then similar to that of Spanish protocol LPA2005 since January 2014. We evaluate the rates of remission, death and overall survival (Kaplan-Meier method). Results: We collected 79 patients. The sex ratio was 1.3 with a median age of 34 years (extreme: 2-75 years). Hyperleukocytosis (GB> 10000 / mm3) was noted in 29 patients (37%). The average white blood cell count was 21900 / mm3. The disseminated intravascular coagulation (DIC) was found in the majority of cases (72% of cases). The t(15,17) was found in 89% of cases. The PML-RARA transcript was positive in 100% of cases. Eight patients (10%) died before treatment with hemorrhage. Thirty three patients were treated by the APL 93 (group1) and thirty eight patients were treated by the protocol LPA2005 (group 2). Fifteen patients (22%) died early during the induction course before evaluation. Causes of death during treatment were multiple: respiratory disease due to the differentiation syndrome, a severe haemorrhagic syndrome and or septic shock. Complete remission was obtained in 55 patients (98% of the evaluable patients and 77% of the treated patients) and one patient failure (2%). No deaths were reported during consolidation or maintenance treatment. A late bone marrow relapse was observed in 8 patients (14,5%). At five years of follow up, overall survival and event-free survival are 66% and 64%, respectively, and relapse-free survival is 77%. Summary/Conclusion: In our series, the DIC rates are correlated with that of the literature, as well as early death rate. The complete remission and overall survival remain lower than that of the literature. This is explained by a high rate of early mortality (during induction) by hemorrhage, of the higher frequency of hyper-leukocyte forms and the delay in diagnosis and management for our patients.