Quantitation of Minimal Residual Disease in Acute Myeloid Leukemia by Tryptase Monitoring Identifies a Group of Patients with a High Risk of Relapse

Purpose: Recent data suggest that tryptase is produced by blast cells in a group of patients with acute myeloid leukemia (AML). In these patients, serum tryptase levels are elevated at diagnosis and decrease to normal ( Patients: In this study, we examined the value of tryptase as a marker of minimal residual AML. In 61 patients with de novo AML exhibiting elevated serum tryptase (>15 ng/mL) at diagnosis, tryptase levels were measured serially during and after chemotherapy by a fluoroenzyme immunoassay. Results: Of the 61 patients, 42 (68.9%) entered hematologic CR in response to induction chemotherapy. Twenty-nine of these 42 patients also entered biochemical remission (BR) defined by a decrease of tryptase levels to normal ( P Conclusion: A persistently elevated tryptase level in AML in CR is indicative of minimal residual AML and associated with a high risk of relapse.