{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,9]],"date-time":"2026-07-09T16:17:27Z","timestamp":1783613847239,"version":"3.55.0"},"reference-count":23,"publisher":"S. Karger AG","license":[{"start":{"date-parts":[[2026,5,9]],"date-time":"2026-05-09T00:00:00Z","timestamp":1778284800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"},{"start":{"date-parts":[[2026,5,9]],"date-time":"2026-05-09T00:00:00Z","timestamp":1778284800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Breast Care"],"abstract":"<jats:p>Introduction: Staging examinations have historically not been standard practice in low-risk early breast cancer (EBC). This study aimed to assess the frequency, modalities, and clinical implications of staging diagnostics in this population, including the incidence of additional imaging, false-positive findings, and metastatic rates, with a comparative focus on HER2-low subgroups. Methods: This retrospective single-center cohort study included all patients diagnosed with low-risk EBC at the University Medical Center Freiburg between 2017 and 2023. Low-risk criteria comprised clinical stage T1\/2, node-negative (N0), hormone receptor-positive (HR+), HER2-low (IHC 1+\/2+ with negative FISH) or HER2-negative (IHC 0) status, and asymptomatic presentation. Demographic, clinicopathological, and staging data were analyzed, including modalities and frequency of staging diagnostics, incidence of subsequent imaging\/biopsies triggered by indeterminate findings, false-positive rates, and metastatic outcomes. HER2 status was classified as: HER2-low: IHC 1+ or 2+ with FISH-negative and HER2-negative: IHC 0 without membrane staining. Comparative analyses examined how metastatic rates and the use of staging procedures differed between the HER2-low subgroups. Results: Of the included patients, 158 (43.5%) had a HER2 IHC 0, 153 (42.2%) had a HER2 IHC 1+, and 52 (14.3%) had a HER2 IHC 2+ with a negative FISH test. The overall risk of distant metastases was 0.8%. Among patients with a HER2 IHC 1+, the metastasis rate was 1 (0.7%); in the HER2 IHC 2+ group, no metastases were observed (0.0%); and in the HER2 IHC 0 group, the metastasis rate was 2 (1.3%) (p = 0.65). A total of 205 patients with confirmed HER2-low status (IHC 1+ or 2+ with negative FISH) were further analyzed regarding staging procedures and follow-up examinations. Due to suspicious findings during initial staging, additional imaging was required in 30 cases (6.4%). In total, 466 staging tests were performed in the HER2-low cohort, resulting in 40 (9.1%) follow-up examinations. Metastases were confirmed in 3 patients (0.8%) following these additional investigations, corresponding to a positive predictive rate of 6.4% in this group. Conclusion: Distant metastases are rare in HER2-low EBC. Overall, staging tests should not be routinely performed in this patient population. This study found no significant difference in the rate of metastasis between patients with a HER2 IHC 0 and those with a HER2-low status.<\/jats:p>","DOI":"10.1159\/000552309","type":"journal-article","created":{"date-parts":[[2026,5,9]],"date-time":"2026-05-09T16:00:28Z","timestamp":1778342428000},"page":"1-8","source":"Crossref","is-referenced-by-count":0,"title":["The Impact of Staging Investigations in HER2-Low, Low-Risk Patients"],"prefix":"10.1159","author":[{"given":"Lisa","family":"Jung","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Markus","family":"Medl","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hannes","family":"Endres","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dorothee","family":"Jakob","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4066-2773","authenticated-orcid":false,"given":"Claudia","family":"Neubauer","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carolin","family":"M\u00fcller","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ingolf","family":"Juhasz-B\u00f6ss","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sarah Isabelle","family":"Huwer","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"127","published-online":{"date-parts":[[2026,5,9]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","DOI":"10.1245\/s10434-018-6486-6"},{"key":"ref2","doi-asserted-by":"publisher","DOI":"10.1038\/sj.bjc.6605323"},{"key":"ref3","doi-asserted-by":"publisher","DOI":"10.2147\/CMAR.S176763"},{"key":"ref4","doi-asserted-by":"publisher","DOI":"10.1677\/ERC-09-0033"},{"key":"ref5","doi-asserted-by":"publisher","DOI":"10.3389\/fcell.2022.923371"},{"key":"ref6","doi-asserted-by":"publisher","DOI":"10.1007\/s00404-023-07169-4"},{"key":"ref7","doi-asserted-by":"publisher","DOI":"10.1634\/theoncologist.2012-0194"},{"key":"ref8","doi-asserted-by":"publisher","DOI":"10.1016\/j.esmoop.2024.102989"},{"key":"ref9","doi-asserted-by":"publisher","DOI":"10.3390\/cancers13051015"},{"key":"ref10","doi-asserted-by":"publisher","DOI":"10.1186\/s13058-022-01519-x"},{"key":"ref11","doi-asserted-by":"publisher","DOI":"10.1016\/j.annonc.2023.11.016"},{"key":"ref12","doi-asserted-by":"publisher","DOI":"10.1007\/s00404-024-07753-2"},{"key":"ref13","doi-asserted-by":"publisher","DOI":"10.1200\/JCO.2018.77.8738"},{"key":"ref14","doi-asserted-by":"publisher","DOI":"10.1016\/j.breast.2012.08.001"},{"key":"ref15","doi-asserted-by":"publisher","DOI":"10.1016\/j.breast.2011.10.005"},{"key":"ref16","doi-asserted-by":"publisher","DOI":"10.1200\/JCO.2012.42.8375"},{"key":"ref17","doi-asserted-by":"publisher","DOI":"10.1016\/j.breast.2016.06.017"},{"key":"ref18","doi-asserted-by":"publisher","DOI":"10.1016\/S1470-2045(21)00301-6"},{"key":"ref19","doi-asserted-by":"publisher","DOI":"10.1016\/j.ijsu.2017.09.004"},{"key":"ref20","doi-asserted-by":"publisher","DOI":"10.1093\/oncolo\/oyad087"},{"key":"ref21","doi-asserted-by":"publisher","DOI":"10.1016\/j.breast.2021.08.016"},{"key":"ref22","doi-asserted-by":"publisher","DOI":"10.1054\/brst.1999.0085"},{"key":"ref23","doi-asserted-by":"publisher","DOI":"10.1159\/000502223"}],"container-title":["Breast Care"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/karger.com\/article-pdf\/doi\/10.1159\/000552309","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,7,9]],"date-time":"2026-07-09T16:00:51Z","timestamp":1783612851000},"score":1,"resource":{"primary":{"URL":"https:\/\/karger.com\/article\/doi\/10.1159\/000552309"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,5,9]]},"references-count":23,"URL":"https:\/\/doi.org\/10.1159\/000552309","archive":["Portico"],"relation":{},"ISSN":["1661-3791","1661-3805"],"issn-type":[{"value":"1661-3791","type":"print"},{"value":"1661-3805","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,5,9]]}}}