Prognostic significance of terminal transferase activity and glucocorticoid receptor levels in acute myeloid leukemia

Abstract

A retrospective study was undertaken to evaluate terminal transferase activity and glucocorticoid receptor content as predictors of prognosis in 52 adult patients with acute myeloid leukemia (AML). Eighteen patients who had detectable levels of TdT in their leukaemic cells (greater than or equal to 0.1 unit microgram-1 DNA), had a higher complete remission rate than patients with low TdT activity. Patients below 60 years with increased TdT activity also had longer survival as compared to those with low TdT levels. By combining cytochemical analysis of peroxidase and immunocytochemical staining for TdT it was possible to show that the enzyme was located in leukaemic cells of myeloid origin. Leukemias of monocytic origin had no detectable TdT activity in 10/11 cases. The cellular content of the cytoplasmic glucocorticoid receptor varied from 0 to 2.8 fmol micrograms-1 DNA. There was no difference in receptor content between the different FAB subgroups. High levels of the receptor (greater than or equal to 0.22 fmol microgram-1 DNA) were positively correlated with the remission rate. Patients with TdT levels of greater than or equal to 0.1 unit microgram-1 DNA and a glucocorticoid receptor concentration of greater than or equal to 0.22 fmol microgram-1 DNA had significantly higher remission (P = 0.001) and survival rates (P = 0.007) compared with those with undectectable levels of both TdT and low receptor content. It is thus concluded that combined measurements of TdT and the glucocorticoid receptor are useful predictors of prognosis in AML.