In vitro chemosensitivity testing in acute non lymphocytic leukemia using the bioluminescence ATP assay

The ATP assay is a short term in vitro chemosensitivity assay where the amount of viable cells are determined by their content of ATP. The aim of the study was to compare the in vitro results of six cytostatic drugs to the clinical outcome in 83 acute non-lymphocytic leukemia (ANLL) patients. The secondary ANLL at diagnosis showed an in vitro resistance to daunorubicin that was significantly higher compared to de novo ANLL at diagnosis (P<0.003). De novo ANLL at diagnosis that achieved complete remission (CR) were significantly more sensitive to daunorubicin compared to those who didn't achieve CR (P<0.05). There was an vitro correlation between topoisomerase II active drugs but not between these drugs and ara-C. In vitro ara-C sensitivity (< or = the median of the de novo ANLL at diagnosis) was correlated to poor overall survival (P = 0.02). In vitro sensitivity to daunorubicin and mitoxantrone was associated with prolonged disease free survival (P = 0.03 and P = 0.04). We conclude that despite significant correlation to clinical parameters for daunorubicin and mitoxantrone the predictive value of the ATP assay in this material was insufficient for directing therapy.