[The preleukemic syndrome. Aspects of the problem and consideration of 5 cases].

Chronic acquired peripheral cytopenia, usually the result of ineffective myelopoiesis, is the main feature of the dysmyelopoiesis described as the preleukaemic syndrome. Probably attributable to a stem cell disorder, this condition may well progress to acute myeloblastic leukaemia. Five cases in which a retrospective diagnosis of preleukaemia was possible are presented. Each patient was followed from the onset of the disease and throughout its entire course. The possibility that the preleukaemic picture might have been secondary to exposure to marrow-damaging agents or an initial paraneoplastic syndrome, or was some other disease (Björkman's acquired sideroblastic anaemia, refractory anaemia with partial Dreyfus myeloblastosis, nocturnal paroxystic haemoglobinuria) was ruled out in all cases.