[Co-operative study of all-trans retinoic acid as a differentiation induction therapy of acute promyelocytic leukemia].

Efficacy and safety of tretinoin (all-trans retinoic acid, ATRA, Ro01-5488) for refractory and relapsed acute promyelocytic leukemia were studied by multi-institutional study in Japan. 22 out of 27 (81.5%) patients with previously untreated who were intolerable to chemotherapy, relapsed and refractory were achieved CR. And 4 out of 11 (36.4%) in relapsed patients who received ATRA remission induction therapy previously responded. Side effects, such as dryness of the lip and skin, headache, increase of triglyceride, beta-lipoprotein and lactate dehydrogenase, were observed in 36 of 41 eligible patients (87.8%) but these were well tolerated. In addition to these, hyperleukocytosis in 4 cases and retinoic acid syndrome in 3 cases were observed. However, all patients were prescribed tretinoin again by adequate management.