Outcome of acute promyelocytic leukemia treated with all trans retinoic acid and chemotherapy in elderly patients: the European group experience

We analyzed the outcome of patients aged more than 60 included in a multicenter trial in newly diagnosed acute promyelocytic leukemia (APL93 trial), which tested the role of early addition of chemotherapy to all trans retinoic acid ( ATRA) and of maintenance with ATRA and/or low-dose chemotherapy. In total, 129/533 (24.2%) patients included in this trial were older than 60. The CR rate was 86% in patients older than 60 as compared to 94.5% in younger patients ( P = 0.0014), due to a higher incidence of early deaths in elderly patients. The 4-year incidence of relapse was 15.6% in adults older than 60 and 23.2% in younger adults although most elderly patients received less intensive consolidation chemotherapy. However, 18.6% of the patients older than 60 years who achieved CR died in CR, mainly from sepsis during consolidation course or maintenance treatment, as compared to 5.7% of younger adults (P<0.001). Thus, overall 4-year survival of elderly patients was 57.8% as compared to 78% in younger adults (P<0.0001). APL in elderly patients appears as sensitive to ATRA-Chemotherapy based regimen as in younger adults. Less favorable outcome is mainly due to an increase of early deaths and to toxicity of consolidation treatment, strongly suggesting a beneficial role for less intensive consolidation chemotherapy and possibly introduction of arsenic derivates in the treatment of APL in the elderly.