{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T06:46:20Z","timestamp":1790318780470,"version":"4.1.0"},"reference-count":22,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2024,5,26]],"date-time":"2024-05-26T00:00:00Z","timestamp":1716681600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Sydney Blood Cancer Research Institute"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>The tyrosine kinase domain of the FMS-Like tyrosine kinase 3 (FLT3-TKD) is recurrently mutated in acute myeloid leukemia (AML). Common molecular techniques used in its detection include PCR and capillary electrophoresis, Sanger sequencing and next-generation sequencing with recognized sensitivity limitations. This study aims to validate the use of droplet digital PCR (ddPCR) in the detection of measurable residual disease (MRD) involving the common FLT3-TKD mutations (D835Y, D835H, D835V, D835E). Twenty-two diagnostic samples, six donor controls, and a commercial D835Y positive control were tested using a commercial Bio-rad\u00ae ddPCR assay. All known variants were identified, and no false positives were detected in the wild-type control (100% specificity and sensitivity). The assays achieved a limit of detection suitable for MRD testing at 0.01% variant allelic fraction. Serial samples from seven intensively-treated patients with FLT3-TKD variants at diagnosis were tested. Five patients demonstrated clearance of FLT3-TKD clones, but two patients had FLT3-TKD persistence in the context of primary refractory disease. In conclusion, ddPCR is suitable for the detection and quantification of FLT3-TKD mutations in the MRD setting; however, the clinical significance and optimal management of MRD positivity require further exploration.<\/jats:p>","DOI":"10.3390\/ijms25115771","type":"journal-article","created":{"date-parts":[[2024,5,27]],"date-time":"2024-05-27T10:12:27Z","timestamp":1716804747000},"page":"5771","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["FLT3-TKD Measurable Residual Disease Detection Using Droplet Digital PCR and Clinical Applications in Acute Myeloid Leukemia"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6688-8511","authenticated-orcid":false,"given":"Eric Wenlong","family":"Li","sequence":"first","affiliation":[{"name":"Institute of Hematology, Royal Prince Alfred Hospital, Sydney, NSW 2050, Australia"},{"name":"Molecular Hematology Laboratory, Royal Prince Alfred Hospital, Sydney, NSW 2050, Australia"},{"name":"Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2050, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ngoc Yen Kim","family":"Tran","sequence":"additional","affiliation":[{"name":"Molecular Hematology Laboratory, Royal Prince Alfred Hospital, Sydney, NSW 2050, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Derek","family":"McCulloch","sequence":"additional","affiliation":[{"name":"Institute of Hematology, Royal Prince Alfred Hospital, Sydney, NSW 2050, Australia"},{"name":"Molecular Hematology Laboratory, Royal Prince Alfred Hospital, Sydney, NSW 2050, Australia"},{"name":"Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2050, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6964-9591","authenticated-orcid":false,"given":"Michael","family":"Krigstein","sequence":"additional","affiliation":[{"name":"Department of Hematology, St Vincent\u2019s Hospital, Sydney, NSW 2010, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alberto","family":"Catalano","sequence":"additional","affiliation":[{"name":"Molecular Hematology Laboratory, Royal Prince Alfred Hospital, Sydney, NSW 2050, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jad","family":"Othman","sequence":"additional","affiliation":[{"name":"Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2050, Australia"},{"name":"Department of Hematology, Royal North Shore Hospital, Sydney, NSW 2065, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Edward","family":"Abadir","sequence":"additional","affiliation":[{"name":"Institute of Hematology, Royal Prince Alfred Hospital, Sydney, NSW 2050, Australia"},{"name":"Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2050, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cheryl","family":"Smith","sequence":"additional","affiliation":[{"name":"Molecular Hematology Laboratory, Royal Prince Alfred Hospital, Sydney, NSW 2050, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Harry","family":"Iland","sequence":"additional","affiliation":[{"name":"Institute of Hematology, Royal Prince Alfred Hospital, Sydney, NSW 2050, Australia"},{"name":"Molecular Hematology Laboratory, Royal Prince Alfred Hospital, Sydney, NSW 2050, Australia"},{"name":"Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2050, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,5,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2073","DOI":"10.1016\/S0140-6736(23)00108-3","article-title":"Acute myeloid leukaemia","volume":"401","author":"DiNardo","year":"2023","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1345","DOI":"10.1182\/blood.2022016867","article-title":"Diagnosis and management of AML in adults: 2022 recommendations from an international expert panel on behalf of the ELN","volume":"140","author":"Wei","year":"2022","journal-title":"Blood"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"2273","DOI":"10.1080\/10428194.2017.1399312","article-title":"The importance of FLT3 mutational analysis in acute myeloid leukemia","volume":"59","author":"Patnaik","year":"2018","journal-title":"Leuk. 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