[Remission of acute promyelocytic leukemia after all-trans-retinoic acid]

This is the first report in Israel of the successful treatment of acute promyelocytic leukemia (APL; M3) with an active metabolite of vitamin A. In a 42-year-old woman with APL all-trans-retinoic acid (ATRA; tretinoin), 45 mg/m2/day was given per os for 90 days. APL is associated with a distinct cytogenetic abnormality: translocation of a portion of the long arm chromosome 17 onto the long arm chromosome 15t (15; 17) with a breakpoint on chromosome 17 in the region of the retinoic acid receptor-alpha (RAR-alpha), playing a crucial role in the leukemogenesis of APL. In man, the drug induces myeloid and mainly promyelocytic leukemic cells to differentiate, without the development of bone marrow hypoplasia. In our patient it caused complete remission and the disappearance of intravascular disseminated coagulation. The only side-effects were a transient macular rash, gastrointestinal symptoms and mild hypertriglyceridemia. Other principal adverse effects reported in the literature are relatively not very serious and consist of dryness of the skin, occasional headaches and intracranial hypertension, nasal congestion, lymphadenopathy, respiratory distress with infiltrates in the lung, bone pain and increased hepatic aminotransferase. A hyperleukocytosis syndrome seems to be more problematic. ATRA appears to be superior to conventional chemotherapeutic regimens. It is safe and highly effective in inducing clinical, morphologic and karyotypic remission with a marked decrease in the expression of the abnormal RAR-message in APL. There is a possible molecular link between the pathogenesis and treatment of this severe and often fatal coagulopathic disease. This therapy of course does not eradicate the leukemic clone, and consolidation chemotherapy or bone marrow transplantation is necessary.(ABSTRACT TRUNCATED AT 250 WORDS)