22. Reducing diagnostic FISH turn-around-time: A rapid pipeline for BCR::ABL1 and PML::RARA suspected leukemias

Successful long-term outcome of patients with BCR::ABL1 positive chronic myeloid leukemia (CML) and PML::RARA positive acute promyelocytic leukemia (APL) is critically dependent on rapid cytogenetic and molecular studies. Fluorescence in situ hybridization (FISH) serves as a standard-of-care diagnostic assay in the workup of suspected BCR::ABL1 and PML::RARA positive leukemias. Nonetheless, turn-around-time for FISH results can be upwards of days, delaying highly-effective personalized treatments. To reduce FISH turn-around-time for patients with a suspected BCR::ABL1 or PML::RARA positive leukemia, our cytogenetics laboratory developed a rapid specimen processing algorithm to consistently return diagnostic BCR::ABL1 and PML::RARA FISH results within 24-hours from sample receipt. Our algorithm, a time-dependent decision matrix, leverages modified sample culturing, harvesting, and FISH hybridization protocols to return diagnostic BCR::ABL1 and PML::RARA FISH results as quickly as 6 hours from sample receipt. This pipeline enables accelerated treatment for patients with BCR::ABL1 and PML::RARA positive leukemias.