[A third complete remission of acute promyelocytic leukemia achieved by administering a gradual increase of all-trans retinoic acid following massive ascites due to retinoic acid syndrome].

A 69-year-old man was diagnosed as having acute promyelocytic leukemia (APL) and was treated with all-trans retinoic acid (ATRA) and idarubicin plus cytarabine. He achieved cytogenetic complete remission (CCR). Relapse occurred 1 year after CCR. Treatment with Am80 gave him a second CCR. However, a second relapse occurred. Re-induction therapy with ATRA was started at 70 mg per day. On day 14, abdominal fullness rapidly increased and massive ascites appeared as a symptom of retinoic acid syndrome (RAS). We ceased the ATRA treatment and started administration of methylprednisolone. The ascites decreased, but an increase of ascites was recognized again temporarily after having re-started ATRA treatment. Thus we gradually increased ATRA administration from 40 mg/day to 70 mg/day of ATRA. RAS did not occur and the patient achieved a third CCR. This case indicates that a gradual increase in ATRA administration is beneficial for RAS occurring in APL patients.