A non-random chromosome abnormality found in precursor-B lineage acute lymphoblastic leukaemia : dic(9;20)(p1?3;q11)

A comparison of cytogenetical data on acute lymphoblastic leukaemia studied at four large European centres has revealed a non-random dicentric chromosome abnormality : dic(9 ;20) (p1 ?3 ;q11) in 10 patients, nine of whom were children. All had early precursor-B lineage ALL, and eight children had a non-standard risk clinical presentation. The origin of the dicentric chromosome was demonstrated using a range of chromosome banding techniques. This was confirmed by FISH using paints and centromeric probes for chromosomes 9 and 20, together with a number of cosmid probes. The follow-up time of these patients is presently too short and the number of patients too few to determine the prognostic significant of this chromosome abnormality. FISH ; precursor-B lineage