Ph1-negative eosinophilic leukaemia with trisomy 8. Case report and review of cytogenetic studies.

A case of eosinophilic leukaemia of the mature cell type in a 73-year-old man is described. Bone marrow chromosomes were studied in direct preparations on 3 occasions. With the G- and Q-banding techniques an extra chromosome number 8 was observed in all metaphases. There was no Ph1-chromosome. Therapy with vincristine and prednisone produced remissions but the course of the disease was accelerated. Review of the literature and study of the present case suggests that eosinophilic leukaemia like CGL may be divided into a Ph1-positive and a Ph1-negative group. In both groups karyotype abnormalities may be present and might herald a downhill course.