Retinoic acid syndrome in patients following the treatment of acute promyelocytic leukemia with all-trans retinoic acid.

BACKGROUND: Retinoic acid syndrome (RAS) is a potentially lethal complication during all-trans retinoic acid (ATRA) treatment of acute promyelocytic leukemia (APL). The incidence and risk factors have been shown to vary in different series. In this study we want to establish the incidence of RAS in our hospital and try to elucidate factors that increase its risk.

METHODS: We retrospectively analyzed 102 patients diagnosed with APL between August 1993 and December 2007 at Chang Gung Memorial Hospital, Taiwan. All patients received ATRA as an induction regimen with or without conventional chemotherapy.

RESULTS: Eight of the 102 patients (7.8%) experienced RAS which developed after a median of 9 days (range: 2 to 23 days) of ATRA treatment. Respiratory distress and fever were the most common presentations, occurring in 7 of 8 patients (87.5%). Age, gender, morphological or molecular subtypes, an initial white blood cell (WBC) count of more than 10 x 10(9)/L and concurrent chemotherapy did not statistically attribute to the occurrence of RAS. One patient developed RAS manifesting with pulmonary hemorrhage but experienced a complete recovery after administration of high-dose dexamethasone. The RAS-related mortality was 12.5% (1 out of 8 patients).

CONCLUSION: The incidence of RAS in this study was similar to those of other series with ATRA and concurrent chemotherapy. Age, gender, morphological or molecular subtypes, an initial leukocyte count of more than 10 x 10(9)/L or the presence of concurrent chemotherapy is not significantly associated with the occurrence of the RAS.