Chronic myelomonocytic leukaemia in a child with constitutional partial trisomy 8 mosaicism.

We present a 3-year-old boy with constitutional partial trisomy 8 mosaicism (karyotype 47,XY, + del(8)(p12)/46,XY) who developed chronic myelomonocytic leukaemia and we review the few reported cases of constitutional trisomy 8 mosaicism (CT8M) associated with malignancy. This case highlights the association between CT8M and the development of malignancies, haematological malignancies in particular.