{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,4]],"date-time":"2026-09-04T05:15:17Z","timestamp":1788498917140,"version":"build-2803163510"},"reference-count":45,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,4]],"date-time":"2026-09-04T00:00:00Z","timestamp":1788480000000},"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 and purpose<\/jats:title>\n                    <jats:p>Proton therapy is commonly delivered for base-of-skull (BOS) tumors to minimize risk of normal-tissue injury. Novel Bragg peak FLASH may improve protection for organs at risk (OARs). We investigated if proton pencil-beam scanning (PBS) Bragg peak FLASH could achieve comparable dosimetry at ultra-high dose rates to conventional-rate (CONV)-intensity-modulated proton therapy (IMPT) for potential clinical use.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Materials and methods<\/jats:title>\n                    <jats:p>\n                      PBS Bragg peak FLASH and CONV-IMPT plans were optimized for 10 consecutive patients with BOS tumor in an in-house treatment-planning system and hypofractionation regimen (30 GyE in five fractions) to assess dosimetric quality while reflecting clinical practice, parameters, and hypothetical fraction doses for FLASH effect. FLASH dose-rate coverage (\n                      <jats:italic>V<\/jats:italic>\n                      <jats:sub>40Gy\/s<\/jats:sub>\n                      ) and dose-rate volume histograms (DRVHs) were quantified across OARs. FLASH (\u226540 Gy\/s) was achieved with a minimum MU per spot of 300\u2013500 and a minimum spot time (MST) of 0.5 ms. FLASH dose-rate coverage, OAR sparing, and target coverage were averaged across all cases.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      FLASH generated higher CTV\n                      <jats:italic>D<\/jats:italic>\n                      <jats:sub>max<\/jats:sub>\n                      than CONV-IMPT (114% vs. 108%). Dose metrics for OARs were comparable between modalities (\n                      <jats:italic>p<\/jats:italic>\n                      &amp;gt; 0.05). Average dose rate (ADR) DRVHs of OARs indicated 74.1%\n                      <jats:italic>V<\/jats:italic>\n                      <jats:sub>40Gy\/s<\/jats:sub>\n                      FLASH dose-rate coverage without dose threshold, and 94.4%\n                      <jats:italic>V<\/jats:italic>\n                      <jats:sub>40Gy\/s<\/jats:sub>\n                      FLASH dose-rate coverage with 1-Gy dose threshold.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>PBS Bragg peak FLASH can deliver conformal target dosimetric coverage, ultra-high dose rates, and comparable OAR dosimetry to CONV-IMPT, suggesting that this novel technique is feasible for BOS tumor FLASH radiotherapy. The study supports future research to explore FLASH\u2019s biological and clinical benefits in BOS tumors and OAR sparing.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fonc.2026.1909184","type":"journal-article","created":{"date-parts":[[2026,9,4]],"date-time":"2026-09-04T04:24:34Z","timestamp":1788495874000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Novel Bragg peak FLASH radiotherapy: treatment of base-of-skull tumors within existing clinical guidelines"],"prefix":"10.3389","volume":"16","author":[{"given":"Michael","family":"Pennock","sequence":"first","affiliation":[{"name":"Department of Radiation Oncology, University of Pittsburgh Hillman Cancer Center","place":["Pittsburgh, PA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Balaji","family":"Selvaraj","sequence":"additional","affiliation":[{"name":"New York Proton Center","place":["New York, NY, United 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