Outcome of a Real-Life Population of Patients With Acute Promyelocytic Leukemia Treated According to the PETHEMA Guidelines: The Polish Adult Leukemia Group (PALG) Experience

Abstract

Background: Acute promyelocytic leukemia (APL) has a favorable prognosis. However, results of randomized studies do not necessarily reflect the outcomes of a real-life population.

Patients and methods: We analyzed 283 unselected APL patients treated in 20 Polish hospitals between 2005 and 2017. All patients were intended to be treated with PETHEMA (Programa Español para el Tratamiento de las Hemopatías Malignas) protocols based on all-trans retinoic acid plus chemotherapy.

Results: The probability of overall survival at 4 years was 67%, while event-free survival was 64%. The early death (ED) rate was 20.1% (n = 57), while 3.5% (n = 10) patients died before induction therapy was started. The main causes of ED included hemorrhage (45.6%), infections (17.5%), and differentiation syndrome (14.5%). Of 273 treated patients, 214 (78.4%) experienced hematologic morphologic remission, 2 (0.7%) were found to have resistant disease, 47 (17.2%) could not be evaluated for response because of ED, and in 6 (3.7%) no data concerning the response were available. Multivariate analyses showed that predictors of ED and overall survival were Eastern Cooperative Oncology Group performance status > 2, age > 60 years, and all types of bleeding episodes that occurred before starting therapy, while an additional predictor of event-free survival was high white blood cell count (> 10 10⁹/L).

Conclusion: ED remains a major problem in APL patients, especially in a real-life population. Shortening of the time between the initial contact with a health care professional, and all-trans retinoic acid administration and the use of appropriate supportive care could improve the outcome of unselected APL population, mainly by reducing the ED rate.

Keywords: ATRA; Acute promyelocytic leukemia; Chemotherapy; Early death; Outcome.