Survival curves of APL patients according to the level of in vitro differentiation of APL blasts at diagnosis.

Patients were separated into 2 groups according to the percentage of differentiated leukemic cells at day 3 of suspension culture in the presence of ATRA (continuous lines indicate a percentage lower than 50%; dotted lines, a percentage greater than 50). (A) Event-free survival. (B) Relapse-free survival. (C) Overall survival.