Automated cytochemistry in acute leukemias. A new approach to the FAB classification based on cell distribution pattern

Flow cytochemical patterns of white blood cells in human haematopoietic malignancies. II. Chronic leukaemias

Peripheral blood samples from 73 patients with chronic leukaemia were measured with the Technicon H-6000 automated haematology analyser to provide flow cytochemical (peroxidase content) and volume (light scatter) discriminated scattergram patterns. For chronic granulocytic leukaemia (CGL), these patterns were so reproducible and distinct that they allowed an immediate diagnosis even without the benefit of microscopic examination. Relative and absolute basophilia was an invariable feature, and remained detected by the H-6000 even when the patient was in haematologic and cytogenetic remission or progressed into blast crisis (BC). Most patients in BC also demonstrated an inordinately high number of large unstained cells (LUC) and high proportions of 'lymphocytes' (small blasts with no peroxidase content by visual inspection). Thus, for patients with CGL, LUC values above 10%, and/or steady increments in the proportion of 'lymphocytes', merit concern as these changes may herald an accelerated phase of disease. The scattergram pattern of untreated chronic lymphocytic leukaemia (CLL) showed a dense accumulation of data points within the lymphocytic 'box' with a small cluster of granulocytic elements. Most patients also had a frankly abnormal proportion of LUC. Sixteen patients with CLL were compared for ratios of LUC to lymphocytes and stage of disease; patients with the most advanced stage (IV) had the highest, statistically significant values, than the patients with more benign disease. Thus, it is possible that follow up with this instrument of patients with CLL will also allow early detection of an impending prolymphocytoid transformation (accelerated phase) of this disease.

Automated leucocyte differential counts in chronic lymphocytic and hairy-cell leukaemias: a comparison of the Hemalog D, H6000 and Coulter S Plus IV

The automated peripheral blood differential counts produced by the Hemalog D, H6000 and Coulter S Plus IV were analysed and compared in 30 cases of chronic lymphocytic leukaemia (CLL) and 12 cases of hairy-cell leukaemia. All three machines were reliable in identifying CLL and HCL as a 'lymphocytosis' and in estimating neutrophil numbers in the disease. The Hemalog D and H6000 produced accurate monocyte counts in the two diseases, but the Coulter S Plus IV was unreliable in this regard since large lymphoid cells were identified as monocytes. The Haemalog D and H6000 were comparable in consistently identifying modestly raised large unstained cells (LUCs) in CLL. The Hemalog D, but not the H6000, was able to distinguish HCL from CLL on the basis of markedly raised LUCs.

Automated leucocyte differential counts in acute leukaemia: a comparison of the Hemalog D, H6000 and Coulter S-plus IV

The automated peripheral blood differential counts produced by the Hemalog D, H6000 and Coulter S-plus IV were analysed in 32 cases of acute leukaemia (22 AML (acute myeloblastic leukaemia); 10 ALL (acute lymphoblastic leukaemia], all with greater than 30% circulating blast cells. All three machines were highly effective in recognizing the presence of an abnormality. With the Hemalog D and H6000, the presence of increased LUC and HPX cells, together with an LPX alarm, was suggestive of acute leukaemia. With the Coulter S-plus IV, multiple alarms indicated the need for further investigation but, since alarms occur in many other situations, their presence was not necessarily suggestive of acute leukaemia. All the machines were of value in distinguishing AML from ALL since 'lymphocytes' were predominant in all cases of ALL and 'neutrophils' the majority cell type in most patients with AML. However, the presence in a minority of cases of AML of large numbers of micromyeloblasts recognized as 'lymphocytes' limited the discriminating power of all three machines. The Hemalog D allowed some definition of subtypes of AML, but the H6000 and Coulter S-plus IV were of no value in this regard.