Treatment of older adults with acute promyelocytic leukaemia.

Only 15 to 20% of acute promyelocytic leukaemia (APL) patients are older than 60 years, and the characteristics and outcome of APL in that age range are not well known. Published studies show that APL in elderly patients has haematological features similar to those of APL in younger patients. However, using the current combination of all-trans retinoic acid (ATRA) and anthracycline-based chemotherapy, the outcome for these patients, although it has much improved, remains less favourable than that for younger patients. This is due to a higher incidence of early deaths and deaths in complete remission (CR), during consolidation chemotherapy courses, whereas the relapse rate appears similar in older and younger adults. Treatment approaches with more limited myelosuppression, especially consolidation chemotherapy with an anthracycline alone (without Ara-C), low-dose maintenance treatment with 6-mercaptopurine, methotrexate and ATRA, and consolidation with arsenic trioxide, should be tested especially in elderly patients in order to replace more toxic 'classical' anthracycline-Ara-C consolidation treatment, after achieving CR with ATRA.