Impact of Ultra Rapid Molecular Profiling on Treatment Delays and Healthcare Utilization of Patients Hospitalized for Acute Leukemia

Background Molecular testing is fundamental to treatment decisions in patients with acute leukemia. The impact of rapid molecular profiling on the timing of treatment initiation and healthcare utilization in patients hospitalized for suspected acute leukemia has not been described. Methods We conducted a retrospective chart review of patients hospitalized and treated for suspected acute leukemia at Massachusetts General Hospital between September 2023 and April 2024. We conducted a detailed workflow analysis comparing the time to obtaining molecular profiling results from admission [“time to results” or TTR] between routine (legacy) methods (i.e., RT-PCT, karyotype, FISH, targeted DNA and RNA sequencing) and an ultra-rapid genomic profiling test (Thermo Fisher Genexus Oncomine Myeloid Panel, or “Genexus”) which was run in parallel. We used linear regression models to evaluate the impact of TTR on time to treatment initiation from admission [TTTI] and hospital length of stay [LOS]. Results Of the 111 patients who had ultra-rapid genomic profiling conducted during the study period, 57 (51.4%) were adult patients who were hospitalized for diagnostic workup and treatment of suspected acute leukemia. The most common leukemia subtypes were acute myeloid leukemia (n=39/57, 68.4%), B-lymphoblastic leukemia (n=9/57, 15.8%), and acute promyelocytic leukemia (n=4/57, 7.0%). The mean TTTI was 5.2 days (range 1-17) and mean LOS was 30.9 days (range 3-86). Genexus had a mean TTR of 3.1 days (range 1-8), whereas legacy methods had a mean TTR of 5.4 days (range 3-10). Longer TTR was associated with longer TTTI (b=0.95; SE=0.20; P=<0.001) and longer LOS (b=4.08; SE=1.30; P=<0.003). Conclusions Ultra-rapid molecular profiling reduces the time to obtaining actionable genetic sequencing results for patients hospitalized for suspected acute leukemia by 2 days compared to legacy methods. Delays in obtaining molecular profiling of these patients is associated with treatment initiation delays and longer hospital length of stay, underscoring the importance of expanded access to ultra-rapid molecular profiling for acute leukemia. Further work is needed to elucidate the full economic impact of ultra-rapid molecular profiling on overall healthcare utilization.