Leukaemia Classification: a Study of the Accuracy of Diagnosis in 456 Patients

Abstract
A panel of 5 hematologists examined, without consultation or prior knowledge of the diagnosis, blood films and bone marrow smears from 456 patients with a diagnosis of leukemia. A diagnostic classification which recognized various subtypes of acute myelogenous leukemia was used but no attempt was made to subdivide acute lymphoblastic leukemia. Complete agreement with the initial diagnosis was low (56.4%) and was particularly poor (45.7%) when the patient had 1 of the forms of acute leukemia. Disagreements which would have involved the patient in a change of treatment were unusual (2.0%). A high degree of diagnostic agreement for patients with leukemia is unlikely from morphological classifications alone.