The Remission and Relapse Status of Acute Leukemia as Studied by the In Vitro Uptake of Tritiated Thymidine by Peripheral Blood Leukocytes

I T IS THE PURPOSE of this study to evaluate the uptake of tritiated thymidine ( H3TdR) by peripheral blood leukocytes as a parameter for assessing various phases of acute leukemia in remission and in relapse. Two recent reports1’2 have documented the persistence of leukemic cells in some patients with acute leukemia diagnosed as being in complete bone marrow remission after therapy. These residual leukemic cells were found using extensive histologic and cytologic tests. The results of the present study suggest that, in addition to the usual morphologic technics, H3TdR uptake by peripheral blood leukocytes in vitro may be useful in the evaluation of patients with acute leukemia.