{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,11]],"date-time":"2026-06-11T21:31:41Z","timestamp":1781213501452,"version":"3.54.1"},"reference-count":25,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2022,5,13]],"date-time":"2022-05-13T00:00:00Z","timestamp":1652400000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cancers"],"abstract":"<jats:p>Background: Proton beam radiotherapy (PBT) offers physical dose advantages that might reduce the risk for secondary malignancies (SM). The aim of the current study is to calculate the risk for SM after X-ray-based 3D conformal (3DCRT) radiotherapy, intensity-modulated radiotherapy (IMRT), and active pencil beam scanned proton therapy (PBS) in patients treated for thymic malignancies. Methods: Comparative treatment plans for each of the different treatment modalities were generated for 17 patients. The risk for radiation-induced SM was estimated using two distinct prediction models\u2014the Dasu and the Schneider model. Results: The total and fatal SM risks estimated using the Dasu model demonstrated significant reductions with the use of PBS relative to both 3DCRT and IMRT for all independent thoracic organs analyzed with the exception of the thyroid gland (p \u2264 0.001). SM rates per 10,000 patients per year per Gy evaluated using the Schneider model also resulted in significant reductions with the use of PBS relative to 3DCRT and IMRT for the lungs, breasts, and esophagus (p \u2264 0.001). Conclusions: PBS achieved superior sparing of relevant OARs compared to 3DCRT and IMRT, leading to a lower risk for radiation-induced SM. PBS should therefore be considered in patients diagnosed with thymic malignancies, particularly young female patients.<\/jats:p>","DOI":"10.3390\/cancers14102409","type":"journal-article","created":{"date-parts":[[2022,5,13]],"date-time":"2022-05-13T08:37:02Z","timestamp":1652431022000},"page":"2409","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Secondary Malignancy Risk Following Proton vs. X-ray Radiotherapy of Thymic Epithelial Tumors: A Comparative Modeling Study of Thoracic Organ-Specific Cancer Risk"],"prefix":"10.3390","volume":"14","author":[{"given":"Laila","family":"K\u00f6nig","sequence":"first","affiliation":[{"name":"Department of Radiation Oncology, Heidelberg University Hospital, 69120 Heidelberg, Germany"},{"name":"Heidelberg Institute of Radiation Oncology (HIRO), 69120 Heidelberg, Germany"},{"name":"National Center for Tumor Diseases (NCT), 69120 Heidelberg, Germany"},{"name":"Heidelberg Ion-Beam Therapy Center (HIT), Department of Radiation Oncology, Heidelberg University Hospital, 69120 Heidelberg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Juliane","family":"H\u00f6rner-Rieber","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Heidelberg University Hospital, 69120 Heidelberg, Germany"},{"name":"Heidelberg Institute of Radiation Oncology (HIRO), 69120 Heidelberg, Germany"},{"name":"National Center for Tumor Diseases (NCT), 69120 Heidelberg, Germany"},{"name":"Heidelberg Ion-Beam Therapy Center (HIT), Department of Radiation Oncology, Heidelberg University Hospital, 69120 Heidelberg, Germany"},{"name":"Clinical Cooperation Unit Radiation Oncology, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Matthew","family":"Forsthoefel","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Radiotherapy Centers of Kentuckiana, Louisville, KY 47130, USA"},{"name":"Department of Radiation Medicine, MedStar Georgetown University Hospital, 3800 Reservoir Road NW, Washington, DC 20007, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peter","family":"Haering","sequence":"additional","affiliation":[{"name":"Department for Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7087-9581","authenticated-orcid":false,"given":"Eva","family":"Meixner","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Heidelberg University Hospital, 69120 Heidelberg, Germany"},{"name":"Heidelberg Institute of Radiation Oncology (HIRO), 69120 Heidelberg, Germany"},{"name":"National Center for Tumor Diseases (NCT), 69120 Heidelberg, Germany"},{"name":"Heidelberg Ion-Beam Therapy Center (HIT), Department of Radiation Oncology, Heidelberg University Hospital, 69120 Heidelberg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0150-1328","authenticated-orcid":false,"given":"Tanja","family":"Eichkorn","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Heidelberg University Hospital, 69120 Heidelberg, Germany"},{"name":"Heidelberg Institute of Radiation Oncology (HIRO), 69120 Heidelberg, Germany"},{"name":"National Center for Tumor Diseases (NCT), 69120 Heidelberg, Germany"},{"name":"Heidelberg Ion-Beam Therapy Center (HIT), Department of Radiation Oncology, Heidelberg University Hospital, 69120 Heidelberg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna","family":"Kr\u00e4mer","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Heidelberg University Hospital, 69120 Heidelberg, Germany"},{"name":"Heidelberg Institute of Radiation Oncology (HIRO), 69120 Heidelberg, Germany"},{"name":"National Center for Tumor Diseases (NCT), 69120 Heidelberg, Germany"},{"name":"Heidelberg Ion-Beam Therapy Center (HIT), Department of Radiation Oncology, Heidelberg University Hospital, 69120 Heidelberg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thomas","family":"Mielke","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Heidelberg University Hospital, 69120 Heidelberg, Germany"},{"name":"Heidelberg Institute of Radiation Oncology (HIRO), 69120 Heidelberg, Germany"},{"name":"National Center for Tumor Diseases (NCT), 69120 Heidelberg, Germany"},{"name":"Heidelberg Ion-Beam Therapy Center (HIT), Department of Radiation Oncology, Heidelberg University Hospital, 69120 Heidelberg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eric","family":"Tonndorf-Martini","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Heidelberg University Hospital, 69120 Heidelberg, Germany"},{"name":"Heidelberg Institute of Radiation Oncology (HIRO), 69120 Heidelberg, Germany"},{"name":"National Center for Tumor Diseases (NCT), 69120 Heidelberg, Germany"},{"name":"Heidelberg Ion-Beam Therapy Center (HIT), Department of Radiation Oncology, Heidelberg University Hospital, 69120 Heidelberg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Matthias F.","family":"Haefner","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Heidelberg University Hospital, 69120 Heidelberg, Germany"},{"name":"Heidelberg Institute of Radiation Oncology (HIRO), 69120 Heidelberg, Germany"},{"name":"National Center for Tumor Diseases (NCT), 69120 Heidelberg, Germany"},{"name":"Heidelberg Ion-Beam Therapy Center (HIT), Department of Radiation Oncology, Heidelberg University Hospital, 69120 Heidelberg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J\u00fcrgen","family":"Debus","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Heidelberg University Hospital, 69120 Heidelberg, Germany"},{"name":"Heidelberg Institute of Radiation Oncology (HIRO), 69120 Heidelberg, Germany"},{"name":"National Center for Tumor Diseases (NCT), 69120 Heidelberg, Germany"},{"name":"Heidelberg Ion-Beam Therapy Center (HIT), Department of Radiation Oncology, Heidelberg University Hospital, 69120 Heidelberg, Germany"},{"name":"Clinical Cooperation Unit Radiation Oncology, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany"},{"name":"German Cancer Consortium (DKTK), Partner Site Heidelberg, 69120 Heidelberg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jonathan W.","family":"Lischalk","sequence":"additional","affiliation":[{"name":"Department of Radiation Medicine, MedStar Georgetown University Hospital, 3800 Reservoir Road NW, Washington, DC 20007, USA"},{"name":"Department of Radiation Oncology, Perlmutter Cancer Center, New York University Langone Hospital\u2014Long Island, 150 Amsterdam Ave., New York, NY 10023, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,5,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1383","DOI":"10.1097\/JTO.0000000000000654","article-title":"The 2015 World Health Organization Classification of Tumors of the Thymus: Continuity and Changes","volume":"10","author":"Marx","year":"2015","journal-title":"J. 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