All-transretinoic acid and chemotherapy in the treatment of acute promyelocytic leukemia

BACKGROUND : All- transretinoic acid (ATRA) and chemotherapy has improved complete remission rates and disease free survival in acute promyelocytic leukemia (APL). There is scanty data from Middle East. AIM : To determine the efficacy of ATRA and multi-agent combination chemotherapy in treatment of APL in a single Centre in Kuwait. SET-UPS AND DESIGN : Tertiary cancer centre, retrospective study. METHODS AND MATERIAL : All newly diagnosed APL patients were treated with oral ATRA 45mg/m2 daily until complete remission (CR), intravenous daunorubicin 50mg/m2 on days 1,3 and 5, cytosine arabinoside 100mg/m2 12hrly on days 1 through 10 and etoposide 100mg/m2 on days 1 through 5. Post remission three courses of intensive consolidation chemotherapy were administered. Since October 1999, maintenance chemotherapy consisting of oral 6 mercaptopurine 90mg/m2 daily, methotrexate 15mg/m2 weekly and ATRA 45mg/m2 for 2 weeks every three months was added. Complete remission rates and duration, relapse rate and toxicity were studied. RESULTS : 22 of 24 evaluable patients (91.6%) achieved CR. The median duration of remission was 13 months (range 2-55 months). Three patients (12.5%) relapsed. Two patients (8.3%) developed retinoic acid syndrome and responded to dexamethasone. Five patients (20.8%) died one each of refractory disease, during remission induction and of relapse. Two patients died while in remission. CONCLUSION :: ATRA and combination chemotherapy results in high complete remission rates and low relapse rate in newly diagnosed APL. Maintenance therapy may be useful in preventing relapses.