Acute promyelocytic leukaemia

Acute promyelocytic leukaemia (APML) is a subtype of AML that differs from AML in prognosis. If discovered and treated in time, the prognosis is excellent, but it is very deadly if not due to the high risk of bleeding. Treatment should be started immediately if APL is suspected before diagnosis. The genotype is t(15;17) PML-RARA.

Diagnosis

Leukopenia and promyelocytes in the peripheral blood. T(15;17) and PML-RARA fusion transcript. High risk disease is when the WBC count is below 10 G/L.

Treatment

All-trans retinoic acid (ATRA) must be given as soon as possible. New is that Arsenic trioxide (ATO) is added into the early phase treatment together with ATRA, resulting in synergy and potential curative treatment. The effect of these agents is to force the malignant promyelocytes to mature. In high-risk disease cytarabine is added.

Maintenance therapy is obligatory. ATRA and low doses of MTX are usually enough.