OBJECTIVETo analyze the long-term therapeutic outcome of patients with acute promyelocytic leukemia(APL).

METHODSNewly diagnosed APL patients were treated with ATRA as induction therapy followed by 3-4 courses of combined consolidation chemotherapy and 2 year maintenance therapy with ATRA and 6-MP + methrotrexate, alternatively. Patients were regularly monitored with nested RT-PCR for PML-RARalpha fusion transcript at the end of consolidation chemotherapy and in the following 4 to 5 years.

RESULTSA total of 81 patients with APL were entered the trial, 75 (92.6%) patients achieved CR. Early death (ED) rate was 6.6%. ED patients had significantly higher WBC count and higher percentage of peripheral promyelocyte than those achieved CR. Of 65 patients received consolidation, 60 (92.3%) were proved PML-RARalpha fusion gene negative at the end of the 3rd courses and 3 (4.6%) the end of the 4th courses of consolidation. The mean follow-up was 21.2 (8-64) months, 6 patients relapsed (relapse rate 9.2%). The 5-year Kaplan-Meier estimates of overall survival (OS) rate was (86.6 +/- 4.6)%. For 65 patients received consolidation therapy, the 5-year relapse-free survival (RFS) rate was 82.7%. COX-regression analyses showed only high WBC count (>10 x 10(9)/L) had an adverse prognostic influence on OS.

CONCLUSIONMore than 80% of APL patients treated with systemic therapy could experience long-term relapse-free survival.