Prediction of therapeutic response in acute leukaemia.

The degree to which anticancer drugs suppressed incorporation of tritiated thymidine into leukaemic cells was measured in 26 patients with acute leukaemia. Subsequent achievement of remission correlated best with suppression by cytosine arabinoside (ara-C). 6 of 7 patients with acute myelocytic and myelomonocytic leukaemia whose cells demonstrated suppression by ara-C of 3H-thymidine incorporation of 15% or less of control counts subsequently achieved remission, while 4 of 6 patients whose cells showed smaller degrees of inhibition did not achieve remission. Patients with acute lymphocytic leukaemia showed a similar pattern.