Monitoring Minimal Residual Disease in the Myeloproliferative Neoplasms: Current Applications and Emerging Approaches

Abstract

The presence of acquired mutations within the JAK2, CALR, and MPL genes in the majority of patients with myeloproliferative neoplasms (MPN) affords the opportunity to utilise these mutations as markers of minimal residual disease (MRD). Reduction of the mutated allele burden has been reported in response to a number of therapeutic modalities including interferon, JAK inhibitors, and allogeneic stem cell transplantation; novel therapies in development will also require assessment of efficacy. Real-time quantitative PCR has been widely adopted for recurrent point mutations with assays demonstrating the specificity, sensitivity, and reproducibility required for clinical utility. More recently, approaches such as digital PCR have demonstrated comparable, if not improved, assay characteristics and are likely to play an increasing role in MRD monitoring. While next-generation sequencing is increasingly valuable as a tool for diagnosis of MPN, its role in the assessment of MRD requires further evaluation.

BCR::ABL1-negative myeloproliferative neoplasms in the era of next-generation sequencing

“…The JAK2V617F mutation is usually detected by allele-specific PCR (Baxter et al, 2005;Scott et al, 2007;Scott, 2011;Tefferi et al, 2016a). Quantitative PCR methods such as RQ-PCR, ddPCR (droplet digital PCR), and NGS (Haslam and Langabeer, 2016;Link-Lenczowska et al, 2018;Arber et al, 2022). Peripheral blood counts, in patients with this mutation, show erythrocytosis, thrombocytosis, and/or leukocytosis.…”

High-throughput sequencing for noninvasive disease detection in hematologic malignancies

“…Primary disease entities are polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). 183 At molecular level, mutations in JAK2 V617F are frequently observed, with ;95% of PV and 50% to 60% of ET/ PMF patients harboring this aberration. However, variants in other genetic regions are also common, including CALR exon 9 (;25% ET, ;35% PMF), MPL exon 10 (;4% PMF, ;1% ET), and JAK2 exon 12 (;4% PV).…”

“…[192][193][194] Some assays have already been used in clinical settings, demonstrating potential future utility for noninvasive disease monitoring. 183,[195][196][197][198] HTS-based approaches are not broadly established yet for routine MPN molecular diagnostics, but their capacity to simultaneously cover multiple genetic variants make them a promising tool for monitoring the genetic complexity of MPN. 184,185,197 Abdelhamid et al demonstrated in a proof-of-principle study robust detection of JAK2 V617F in PB by HTS with high concordance to qPCR, even at low AFs.…”

Detecting CALR mutations in splanchnic vein thrombosis: Who and how?

“…[ 26 ] Whether this phenomenon is also observed in patients with CALR + SVT remains to be answered. Given the number of methodological approaches available for the detection of CALR mutations,[ 27 , 28 ] careful validation and selection of a sensitive technique is required so as not to underdiagnose the potential underlying MPN. Secondly, all the pathologically annotated, MPN-associated CALR indel mutations result in a +1 alteration of the reading frame leading to a loss of the terminal calreticulin localization domain.…”