Acute leukemia characterized by trisomy 8 in Down's syndrome

Of the myeloproliferative disorders which develop in Down's syndrome, acute leukemia associated with trisomy 8 has distinct characteristics. It is non-lymphoblastic in type and has a preleukemia phase in which thrombocytopenia is a prominent feature. One case occurring in a 20 mth-old girl is reported and 3 other similar cases reviewed. Acquired trisomy 8 in Down's syndrome is linked to leukemogenesis and confers non-lymphoblastic differentiation.