Familial occurrence of chronic neutrophilic leukaemia

A father and son who both developed chronic neutrophilic leukaemia (CNL) ar e reported. The father, aged 63, had been exposed to radioactive fallout af ter the atomic bomb attack on Hiroshima; he presented with hepatosplenomega ly and neutrophilic leucocytosis, and died of intracerebral haemorrhage 1 m onth after diagnosis. 4 years later his son, then aged 44, presented with n eutrophilic leucocytosis, Leukaemic transformation to acute myelogenous leu kaemia (AML-M1) occurred, and he died of refractory leukaemia 4 months afte r the diagnosis of CNL. This is the first report of this rare disease occur ring in family members; genetic effect due to radioactive poisoning was sus pected in the development of CNL in these two cases.