PB1745 CLINICAL FEATURES AND TREATMENT OUTCOME OF 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 is 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 2017. The diagnosis of APL is based on morphological, cytogenetic and molecular study. The specific treatment is similar that of the French protocol APL93 until 2013, and then similar that of Spanish protocol APL2005 since January 2014.The treatment regimen includes an induction treatment combining ATRA and chemotherapy followed by 2 consolidation courses in the APL93 protocol and 3 consolidation courses in the APL 2005 protocol followed by a 2‐year maintenance treatment with methotrexate, mercaptopurine and ATRA. We evaluate the rates of remission, death and overall survival (Kaplan‐Meier method).Results:We collected 60 patients. The sex ratio was 1.32 with a median age of 32 years (extreme: 2‐75 years). Hyperleukocytosis (GB > 10000 / mm3) was noted in 20 patients (33%). The average white blood cell count was 12995 / mm3. The disseminated intravascular coagulation (DIC) was found in the majority of cases (67% of cases). The t(15,17) was found in 86.1% of cases. The PML‐RARAα transcript was positive in 100% of cases. Seven patients (11.6%) died before treatment with cerebral hemorrhage. Thirty one patients were treated by the APL 93 (group1) and twenty two patients were treated by the protocol APL2005 (group 2). Ten patients (16.7%) died early between days 2 and 5 of the induction course. Forty three patients were evaluable for induction therapy. Complete remission was obtained in thirty nine patients (91% of the evaluable patients and 70% of the treated patients) and tow patient failure (4%). No death was reported during consolidation or maintenance treatment. A late bone marrow relapse was observed in 5 patients (12%), one patient in the group 2 and four patients in the group 1. At five years of follow up, overall survival and event‐free survival are 71% and 55.9%, respectively, and relapse‐free survival is 77%.Summary/Conclusion:In our series, the DIC rates is correlated that of the literature. It would be increase the early death rate by hemorrhage syndrome. The complete remission and overall survival are improved with the APL 2005 protocol, but there remain lower than that of the literature. This is explained by a high rate of early mortality (before7 days of induction) by cerebral hemorrhage, of the higher frequency of hyper‐leukocyte forms and the delay in diagnosis and management for our patients.