[Light- and electron microscopic cytochemistry in blastic leukaemias]

Cytochemistry and membrane markers in acute lymphatic leukaemia (ALL)

136 patients suffering from ALL were subdivided into 5 subtypes (C-ALL, C/T-ALL, pre-T-ALL, B-ALL) according to rosetting tests and using specific antisera directed against membrane antigens. In addition, leukaemic blasts of all patients were investigated according to morphological and cytochemical criteria. In APh and ANAE, indices and the percentages of cases showing a granular staining pattern were high in pre-T- and in T-ALL, but low in C/T- and in C-ALL. PAS-staining, conversely, was more pronounced in C/T- and C-ALL. APh proved to be more discriminative for recognition of the T- and pre-T-ALL subgroups than ANAE, but ANAE-cytochemistry may be useful to detect contaminating normal T-lymphocytes in ALL. Receptors for C3 were more frequent in C- and in T-ALL than in C/T- and in pre-T-ALL, receptors for Fc were distributed equally among all subtypes. Positively of C3- and Fc-receptors was not correlated with cytochemical results. Morphological criteria were not sufficient for subclassification of ALL; the combination of APh- and PAS-staining, however, is valuable to differentiate between C-subgroups and T-subgroups.

[Significance of PAS-positive myeloblastic leukemia]

We refer to 48 adult patients suffering from acute myeloblastic leukemia, whose leukemic cells showed a typical cytochemical pattern: i.e. weak staining for peroxydase and with sudanblack B and lacking or only weak staining for nonspecific esterase. In 8 patients the leukemic myeloblasts additionally showed distinct granular staining for polysaccharides using the PAS-reaction. The therapeutic response, the remission rate and the survival time of these 8 cases have been compared to those of 40 patients, whose leukemic myeloblasts differed exclusively in the absence of granular PAS-positive materials. Out of the latter PAS-negative cases 7 patients (18%) went into a complete remission (M1, P1), 5 patients achieved partial remission (M2, P1-2), the 50%-survival time was 4.9 months. Out of the 8 granular PAS-positive cases 4 patients (50%) went into complete (M1, P1), and 1 reached partial remission (M2, P1-2). The 50%-survival time of the cases now lasts 10.1 months and three patients are still alive and in persisting complete remission 19, 12.5 and 12 months after diagnosis. These results suggest a better prognosis and an improved therapeutic response in those myeloblastic leukemias which additionally contain cytoplasmic granular PAS-positive materials.