Ewan was diagnosed with an aggressive form of acute lymphoblastic leukemia (ALL). It is considered very high risk (VHR) for relapse. This means that even if it is cleared out of his blood and marrow now, it is likely to return. The reason for this is a mixed lineage leukemia (MLL) gene. Ewan has a translocation involving the chromosome band 11q23 where there is a swap of information on chromosomes 9 and 11, t(11;19).