{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,10]],"date-time":"2026-07-10T16:04:31Z","timestamp":1783699471036,"version":"3.55.0"},"reference-count":31,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2025,6,17]],"date-time":"2025-06-17T00:00:00Z","timestamp":1750118400000},"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\/Objectives: Adjuvant radiation for gynecologic malignancies often exposes organs at risk (OARs), such as the bone marrow, bowel, rectum, and bladder, to radiation, leading to toxicities that impact treatment tolerance and patient quality of life. Scanning proton beam therapy, particularly with Individual Field Simultaneous Optimization (IFSO), may offer dosimetric and biological advantages over volumetric modulated arc therapy (VMAT). This study evaluates the clinical impact of IFSO-based proton planning in post-operative gynecologic cancer patients. Materials and Methods: Fourteen patients receiving adjuvant proton therapy to 45 Gy in 25 fractions were retrospectively analyzed. Comparison VMAT plans were generated on the same datasets. Dose\u2013volume metrics for key OARs and normal tissue complication probabilities (NTCPs) were compared using paired statistical tests. Robustness evaluations accounted for setup and range uncertainties. Results: Proton plans significantly reduced dose to bone marrow (V10Gy: 58% vs. 86%, p &lt; 0.00001; V20Gy: 47% vs. 58%, p &lt; 0.00001), small bowel (V20Gy: 21% vs. 56%, p &lt; 0.00001), and femoral heads (left femoral head mean: 11Gy vs. 13Gy, p = 0.032; right femoral head mean: 11Gy vs. 13Gy, p = 0.022). NTCP modeling predicted significantly lower rates of bowel urgency (9.4% vs. 3.3%, p &lt; 0.001) and hematologic toxicity (10.2% vs. 4.9%, p &lt; 0.001) with proton therapy. Plans remained robust across uncertainty scenarios. Conclusions: IFSO-based scanning proton therapy provides clinically meaningful sparing of bone marrow and bowel, with the potential to reduce hematologic and gastrointestinal toxicities. These findings support its use in patients receiving adjuvant pelvic radiotherapy, particularly those undergoing extended field treatment or chemotherapy.<\/jats:p>","DOI":"10.3390\/cancers17122010","type":"journal-article","created":{"date-parts":[[2025,6,17]],"date-time":"2025-06-17T03:37:07Z","timestamp":1750131427000},"page":"2010","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Dosimetric Advantage of Scanning Beam Proton Therapy in Gynecologic Patients Receiving Adjuvant Radiotherapy"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1244-7160","authenticated-orcid":false,"given":"Rachel B.","family":"Ger","sequence":"first","affiliation":[{"name":"Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-8886-7578","authenticated-orcid":false,"given":"Jarrod M.","family":"Lentz","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Cancer Care Northwest, Spokane Valley, WA 99216, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joshua S.","family":"Niedzielski","sequence":"additional","affiliation":[{"name":"Department of Radiation Physics, MD Anderson Cancer Center, Houston, TX 77030, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sujay A.","family":"Vora","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ 85054, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3309-9396","authenticated-orcid":false,"given":"Martin","family":"Bues","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ 85054, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Danairis","family":"Hernandez Morales","sequence":"additional","affiliation":[{"name":"West County Radiological Group, St. Louis, MO 63141, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Justin D.","family":"Anderson","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Baptist Health, Louisville, KY 40207, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-7545-6260","authenticated-orcid":false,"given":"Christopher J.","family":"Kutyreff","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, St. Jude Children\u2019s Hospital, Memphis, TN 38105, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christie A.","family":"Schulz","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ 85054, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pedro R.","family":"Lara","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ 85054, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ana K.","family":"Ridgway","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ 85054, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pamela R.","family":"Lemish","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ 85054, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Justin D.","family":"Gagneur","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ 85054, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aman","family":"Anand","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ 85054, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,6,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"87","DOI":"10.3322\/caac.21262","article-title":"Global Cancer Statistics, 2012","volume":"65","author":"Torre","year":"2015","journal-title":"CA Cancer J. 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