Will ALL leukaemia convert to AML leukaemia if untreated?

Acute leukaemias are generally of 2 types – acute myeloid leukaemia (AML) and acute lymphoid leukaemia (ALL) based on the cell of origin. Their behaviour, response to therapy and prognosis are different. An ALL will not convert to AML or vice-versa except as an occurrence of second malignancy (very rare) following cure of the primary disease.