{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,10]],"date-time":"2026-09-10T05:09:29Z","timestamp":1789016969805,"version":"build-2803163510"},"reference-count":41,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,10]],"date-time":"2026-09-10T00:00:00Z","timestamp":1788998400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Oncol."],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>The emergence of HER2-low breast cancer as a distinct clinical entity has challenged the traditional binary classification of HER2 status. This systematic review aims to evaluate the disparities in Progression-Free Survival (PFS) and Overall Survival (OS) between HER2-low and HER2-positive breast cancer patients.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>A systematic search was performed across PubMed, Scopus, Cochrane Library, ESMO and ASCO for studies published through January 2026. The Clinical trials and observational studies reporting Progression-Free Survival (PFS) and Overall Survival (OS) with Hazard Ratios (HR) were included. Due to significant clinical and methodological heterogeneity, a formal meta-analysis was deemed inappropriate; consequently, evidence was synthesized qualitatively following the Synthesis Without Meta-analysis (SWiM) guidelines. The protocol was prospectively registered in PROSPERO (CRD420261293004).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>A total of 536 records were identified; after removing 356 duplicates, 180 were screened, and 10 trials met the inclusion criteria. Preliminary synthesis indicates that HER2-low tumors exhibit distinct survival trajectories compared to HER2-positive cohorts, often influenced by Hormone Receptor (HR) co-expression and the type of targeted therapy received.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Understanding survival disparities is crucial for optimizing treatment sequencing in the era of antibody-drug conjugates (ADCs).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Systematic review registration<\/jats:title>\n                    <jats:p>\n                      <jats:ext-link>https:\/\/www.crd.york.ac.uk\/prospero\/<\/jats:ext-link>\n                      , identifier CRD420261293004.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fonc.2026.1839945","type":"journal-article","created":{"date-parts":[[2026,9,10]],"date-time":"2026-09-10T04:28:42Z","timestamp":1789014522000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Survival disparities in HER2-low versus HER2-positive breast cancer: a systematic review of progression-free survival and overall survival"],"prefix":"10.3389","volume":"16","author":[{"given":"Widyanti","family":"Soewoto","sequence":"first","affiliation":[{"name":"Department of Surgical Oncology, Faculty of Medicine, Sebelas Maret University, Dr. Moewardi Hospital","place":["Surakarta, Indonesia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ida Bagus Budhi","family":"S. A.","sequence":"additional","affiliation":[{"name":"Department of Digestive Surgery, Faculty of Medicine, Sebelas Maret University, Dr. Moewardi Hospital","place":["Surakarta, Indonesia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"family":"Wibisono","sequence":"additional","affiliation":[{"name":"Department of Urology, Faculty of Medicine, Sebelas Maret University, Dr. Moewardi Hospital","place":["Surakarta, Indonesia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kristanto Yuli","family":"Yarso","sequence":"additional","affiliation":[{"name":"Department of Surgical Oncology, Faculty of Medicine, Sebelas Maret University, Dr. Moewardi Hospital","place":["Surakarta, Indonesia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joko Wibowo","family":"Sentoso","sequence":"additional","affiliation":[{"name":"Department of Surgery, Faculty of Medicine, Sebelas Maret University, Dr. Moewardi Hospital","place":["Surakarta, 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