{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,22]],"date-time":"2026-04-22T11:44:38Z","timestamp":1776858278989,"version":"3.51.2"},"reference-count":28,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2026,4,22]],"date-time":"2026-04-22T00:00:00Z","timestamp":1776816000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,4,22]],"date-time":"2026-04-22T00:00:00Z","timestamp":1776816000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/501100002462","name":"Chungnam National University","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100002462","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Blood Res."],"published-print":{"date-parts":[[2026,12]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background\/Aim<\/jats:title>\n                    <jats:p>\n                      This study retrospectively examined the clinical implications of monitoring\n                      <jats:italic>JAK2<\/jats:italic>\n                      V617F, with a particular focus on disease transformation, in a Korean population of patients with essential thrombocythemia (ET).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      Medical records of patients diagnosed with ET between January 1996 and December 2021 at Chungnam National University Hospital, Daejeon, Korea, were reviewed. Both episodic changes (increase or decrease) and longitudinal patterns of change (stable, gradual increase, or gradual decrease) in\n                      <jats:italic>JAK2<\/jats:italic>\n                      V617F variant allele frequency (VAF), measured at 1-year intervals, were analyzed.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Among the 87 patients who had\n                      <jats:italic>JAK2<\/jats:italic>\n                      V617F VAF measured at least three times, 23 (26.4%), 21 (24.1%), and 16 (18.4%) experienced increases of\u2009\u2265\u200925%,\u2009\u2265\u200950%, and\u2009\u2265\u2009100%, respectively, while 27 (42.5%), 26 (29.9%), and 2 (2.3%) experienced decreases of\u2009\u2265\u200925%,\u2009\u2265\u200950%, and 100%, respectively. Patients with VAF increases had significantly poorer transformation-free survival than those without increases (15-year survival for\u2009\u2265\u200950% increase: 79.2%\n                      <jats:italic>vs.<\/jats:italic>\n                      97.5%;\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.007). Regarding the longitudinal patterns, 62 (71.3%), 13 (14.9%), and 12 (13.8%) patients were classified as having stable, gradual increase, and gradual decrease patterns, respectively. Transformation-free survival was worse in patients with a gradual increase and better in those with a gradual decrease than in those with a stable pattern (20-year survival: 100%\n                      <jats:italic>vs.<\/jats:italic>\n                      88.8%\n                      <jats:italic>vs.<\/jats:italic>\n                      31.3%;\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.026).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>\n                      An increasing\n                      <jats:italic>JAK2<\/jats:italic>\n                      V617F allele burden over time is associated with disease transformation in ET, supporting the need for the ongoing monitoring of\n                      <jats:italic>JAK2<\/jats:italic>\n                      V617F VAF in these patients.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.1007\/s44313-026-00137-2","type":"journal-article","created":{"date-parts":[[2026,4,22]],"date-time":"2026-04-22T10:04:13Z","timestamp":1776852253000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Monitoring of JAK2V617F allele burden in patients with essential thrombocythemia"],"prefix":"10.1007","volume":"61","author":[{"given":"Jeong Suk","family":"Koh","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wonhyoung","family":"Seo","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sora","family":"Kang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Myung-Won","family":"Lee","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hyewon","family":"Ryu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Seung-Woo","family":"Baek","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ik-Chan","family":"Song","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hyo-Jin","family":"Lee","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Deog-Yeon","family":"Jo","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2026,4,22]]},"reference":[{"key":"137_CR1","doi-asserted-by":"publisher","first-page":"1190","DOI":"10.3904\/kjim.2020.634","volume":"36","author":"IC Song","year":"2021","unstructured":"Song IC, Yeon SH, Lee MW, et al. 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