All trans retinoic acid in acute promyelocytic leukaemia: Case series and review of literature

Over the past few years All Trans-Retinoic Acid (ATRA) has been increasingly used to induce remission in Acute Promyelocytic Leukaemia (APL). ATRA is thought to restore the structural integrity of the nuclear bodies which are disrupted by the transcribed chimeric protein (APL-RARα) formed as a result of a specific non-random chromosomal translocation (15:17). Six patients of APL with ATRA were treated at a dose of 45 mg/m² orally. There were five female and one male patient. Five patients presented with pancytopenia while all had a picture of disseminated intravascular coagulation (DIC). Four out of six patients entered into complete remission either on ATRA alone or with the addition of cytotoxic chemotherapy. The other two patients developed serious side effects and the treatment with ATRA had to be stopped. One of these patients subsequently entered into remission with standard chemotherapy. The mean time to remission was 39 days. Since ATRA does not induce cytotoxicity, the problem of marrow suppression and exacerbation of DIC were largely alleviated. The patients remained at home for the most part of their treatment. Relevant literature is reviewed.