Quantification of JAK2V617F mutation load by droplet digital PCR can aid in diagnosis of myeloproliferative neoplasms.

INTRODUCTION This study developed a method for quantifying the JAK2V617F mutation load in patients with myeloproliferative neoplasm (MPN) using droplet digital PCR (ddPCR), which provides a new laboratory method for diagnosing polycythemia vera (PV), essential thrombocythemia (ET), and pre-primary myelofibrosis (pre-PMF). METHODS Patients with MPN who had JAK2V617F mutations from March 2013 to August 2019 were enrolled in this study. JAK2V617F mutation loads were quantified using ddPCR technology. RESULTS The study examined 225 patients, including 135 with ET, 58 with PV, and 32 with PMF. JAK2V617F mutation loads significantly differed (P < .001) between the ET and PV groups and between the ET and PMF groups. Bone marrow biopsies were reclassified in accordance with the 2016 World Health Organization diagnostic criteria, which revealed 132 patients with MPN: 62 with ET, 35 with PV, 17 with pre-PMF, and 18 with overt-PMF. JAK2V617F mutation loads significantly differed (P < .001) between the ET and PV groups and between the ET and pre-PMF groups. The cutoff value between the ET and pre-PMF groups was 49.9. CONCLUSION JAK2V617F mutation loads provide an additional basis for diagnosis of ET, PV, and PMF, particularly regarding differentiation between ET and pre-PMF.