{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,21]],"date-time":"2026-07-21T04:42:12Z","timestamp":1784608932937,"version":"3.55.0"},"reference-count":51,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2022,12,24]],"date-time":"2022-12-24T00:00:00Z","timestamp":1671840000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001659","name":"Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) Clinician Scientist Program OrganAge","doi-asserted-by":"publisher","award":["413668513"],"award-info":[{"award-number":["413668513"]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Interdisciplinary Center of Clinical Research of the Medical Faculty Jena","award":["413668513"],"award-info":[{"award-number":["413668513"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Current Oncology"],"abstract":"<jats:p>Background: Adjuvant radiotherapy (RT) is an integral component of a multidisciplinary treatment strategy for early-stage breast cancer. It significantly reduces the incidence of loco-regional recurrence but also of distant events. Distant events are due to tumor cells disseminated from the primary tumor into lymphatic fluid or blood, circulating epithelial tumor cells (CETC\/CTC), which can reach distant tissues and regrow into metastases. The purpose of this study is to determine changes in the number of CETC\/CTC in the course of adjuvant RT, and to evaluate whether they are correlated to local recurrence and distant metastases in breast cancer patients. Methods: Blood from 165 patients irradiated between 2002 and 2012 was analyzed 0\u20136 weeks prior to and 0\u20136 weeks after RT using the maintrac\u00ae method, and patients were followed over a median period of 8.97 (1.16\u201319.09) years. Results: Patients with an increase in CETC\/CTC numbers over the course of adjuvant RT had a significantly worse disease-free survival (p = 0.004) than patients with stable or decreasing CETC\/CTC numbers. CETC\/CTC behavior was the most important factor in predicting subsequent relapse-free survival. In particular, patients who had received neoadjuvant chemotherapy were disproportionately more likely to develop metastases when cell counts increased over the course of RT (p = 0.003; hazard ratio 4.886). Conclusions: Using the maintrac\u00ae method, CETC\/CTC were detected in almost all breast cancer patients after surgery. The increase in CETC\/CTC numbers over the course of RT represents a potential predictive biomarker to judge relative risk\/benefit in patients with early breast cancer. The results of this study highlight the need for prospective clinical trials on CETC\/CTC status as a predictive criterion and for individualization of treatment. Clinical Trial registration: The trial is registered (2 May 2019) at trials.gov under NCT03935802.<\/jats:p>","DOI":"10.3390\/curroncol30010021","type":"journal-article","created":{"date-parts":[[2022,12,27]],"date-time":"2022-12-27T07:33:33Z","timestamp":1672126413000},"page":"261-273","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Increased Circulating Epithelial Tumor Cells (CETC\/CTC) over the Course of Adjuvant Radiotherapy Is a Predictor of Less Favorable Outcome in Patients with Early-Stage Breast Cancer"],"prefix":"10.3390","volume":"30","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9662-3082","authenticated-orcid":false,"given":"Matthias","family":"M\u00e4urer","sequence":"first","affiliation":[{"name":"Department of Radiotherapy and Radiation Oncology, University Hospital Jena, Bachstra\u00dfe 18, 07743 Jena, Germany"},{"name":"Clinician Scientist Program OrganAge, Interdisciplinary Center for Clinical Research (IZKF), Jena University Hospital, 07747 Jena, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dorothea","family":"Schott","sequence":"additional","affiliation":[{"name":"Transfusionsmedizinisches Zentrum Bayreuth, Kurpromenade 2, 95448 Bayreuth, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6599-3731","authenticated-orcid":false,"given":"Monika","family":"Pizon","sequence":"additional","affiliation":[{"name":"Transfusionsmedizinisches Zentrum Bayreuth, Kurpromenade 2, 95448 Bayreuth, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sonia","family":"Drozdz","sequence":"additional","affiliation":[{"name":"Department of Radiotherapy and Radiation Oncology, University Hospital Jena, Bachstra\u00dfe 18, 07743 Jena, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thomas","family":"Wendt","sequence":"additional","affiliation":[{"name":"Department of Radiotherapy and Radiation Oncology, University Hospital Jena, Bachstra\u00dfe 18, 07743 Jena, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrea","family":"Wittig","sequence":"additional","affiliation":[{"name":"Department of Radiotherapy and Radiation Oncology, University Hospital Jena, Bachstra\u00dfe 18, 07743 Jena, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Katharina","family":"Pachmann","sequence":"additional","affiliation":[{"name":"Transfusionsmedizinisches Zentrum Bayreuth, Kurpromenade 2, 95448 Bayreuth, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"135","DOI":"10.3322\/caac.21209","article-title":"Progress and controversies: Radiation therapy for invasive breast cancer","volume":"64","author":"Jagsi","year":"2014","journal-title":"CA Cancer J. 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