International Journal of Particle Therapy最新文献

{"title":"Treatment Outcomes of Radiation Therapy of Paragangliomas of the Head and Neck at a Single Institution.","authors":"Aleena A Abbasi, Robert A Lustig, Jay F Dorsey, Sean M Grady, John Y K Lee, Goldie A Kurtz, Jacob E Shabason, Keith A Cengel, Douglas C Bigelow, Jason A Brant, Michael J Ruckenstein, Christopher H Rassekh, Katherine L Nathanson, Anna Raper, Yonghong Huan, Michelle Alonso-Basanta","doi":"10.1016/j.ijpt.2026.101956","DOIUrl":"10.1016/j.ijpt.2026.101956","url":null,"abstract":"<p><strong>Background/objectives: </strong>Stereotactic radiosurgery and photon therapy for the locoregional management of head and neck paragangliomas (HNPGLs) have been shown to provide long-term tumor control and symptomatic relief. We report proton therapy (PT) outcomes for HNPGLs at a single institution and describe stereotactic radiosurgery (SRS) and intensity-modulated radiation therapy (IMRT) outcomes as institutional context for modality selection. The primary goal is to report outcomes including tumor control, toxicity, and overall recovery, while evaluating differences across radiation modalities.</p><p><strong>Materials/methods: </strong>This is a retrospective review of 52 adult patients with 54 non-metastatic HNPGLs receiving radiation therapy in a single institution. There were 9 tumors treated with IMRT, 23 with SRS, and 22 with PT. Median dose was 45 Gy (cobalt Gray equivalent [CGE]).</p><p><strong>Results: </strong>Out of 52 patients (14 male, 38 female) with a current median age of 65 (range 27-93), there were 30 jugular paragangliomas (PGLs), 1 tympanic PGL, 8 jugulotympanic PGLs, 3 vagal PGLs, 11 carotid body tumors, and 1 spinal PGL. The median age at the start of treatment was 59.5 years (range 18-85). Median follow-up was 50.3 months (range 3.6-147.2 months), with 52 (100%) patients alive at last follow-up. Local control, distant control, and overall survival were 98%, 100%, and 100%, respectively. No grade 3 to 5 toxicities were reported. At the end of follow-up, 53 (98%) tumors had a partial treatment response or were stable, and 20 (37%) experienced a decrease in volume. Of the 20 tumors that had a decrease in volume, 8 were treated with PT, 8 with SRS, and 4 with IMRT. PT was used more frequently for larger or anatomically complex tumors; SRS was preferred for small, well-circumscribed lesions; and IMRT was selected for moderate-sized or irregularly shaped tumors near critical structures before PT was available.</p><p><strong>Conclusion: </strong>PT was particularly useful in treating large or anatomically complex tumors, while SRS and IMRT offered strong outcomes for smaller or anatomically suitable lesions. We report favorable feasibility, local tumor control, survival, and toxicity of PT for HNPGLs.</p>","PeriodicalId":36923,"journal":{"name":"International Journal of Particle Therapy","volume":"21 ","pages":"101956"},"PeriodicalIF":2.0,"publicationDate":"2026-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13562065/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148956723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Artificial Intelligence in Particle Therapy Treatment Planning: Current Advances and Future Directions.","authors":"James C L Chow, Huan Giap","doi":"10.1016/j.ijpt.2026.101954","DOIUrl":"10.1016/j.ijpt.2026.101954","url":null,"abstract":"<p><strong>Purpose: </strong>This review examines the role of artificial intelligence (AI) in particle therapy treatment planning, highlighting recent advancements, clinical potential, and existing challenges.</p><p><strong>Methods and materials: </strong>A review was conducted on AI applications in proton and heavy ion therapy, focusing on automated plan generation, dose prediction, treatment adaptation, and quality assurance.</p><p><strong>Results: </strong>AI-driven methods have shown promise in optimizing treatment planning, enhancing dose prediction, and improving plan adaptation. However, challenges such as data limitations, model interpretability, and regulatory barriers hinder clinical implementation.</p><p><strong>Conclusion: </strong>While AI offers significant potential to improve particle therapy treatment planning, further research is needed to enhance model robustness, clinical validation, and integration into existing workflows.</p>","PeriodicalId":36923,"journal":{"name":"International Journal of Particle Therapy","volume":"21 ","pages":"101954"},"PeriodicalIF":2.0,"publicationDate":"2026-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13571745/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148963766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Proton Therapy for Head and Neck Adenoid Cystic Carcinoma: A Multi-institutional Review.","authors":"Lisa A McGee, Astha Rohit, Matthew Buras, Gopal Bajaj, John H Chang, Noah S Kalman, Ryan Grover, Adil Akthar, Adam J Kole, Mark McDonald, Sanford Katz, Nancy Lee, Henry Tsai, James Urbanic, Carlos Vargas, Jing Zeng, Jason Molitoris, Scott Lester, Homan Mohammadi, Adam Holtzman","doi":"10.1016/j.ijpt.2026.101320","DOIUrl":"10.1016/j.ijpt.2026.101320","url":null,"abstract":"<p><strong>Purpose: </strong>To evaluate efficacy and toxicity (CTCAE v4.0) outcomes in patients with adenoid cystic carcinoma (ACC) treated with proton beam therapy (PBT).</p><p><strong>Patients and methods: </strong>From 2012 through 2023, 79 patients with non-metastatic ACC were treated with PBT and enrolled on the Proton Collaborative Group (PCG) registry. Kaplan-Meier analyses quantified locoregional control (LRC), disease-free survival (DFS), and overall survival (OS). ACC patients receiving reirradiation with PBT were excluded from this analysis.</p><p><strong>Results: </strong>Median follow-up was 3 years (0.01-6.72). Twenty-six patients were unable to undergo surgery and received definitive PBT versus postoperative PBT (n=53). Median postoperative PBT dose was 66 GyE and 70 GyE for definitive patients treated with conventional fractionation. Most patients had localized disease (n=75); few had nodal metastases (n=4). 62% were locally advanced (T3-T4) at the time of PBT treatment. 3-year Locoregional control (LRC) for all patients was 98% [95% CI (94.3, 100)]. Advanced T-staging, positive margins and definitive-intent PBT were not associated with worsened LRC. 3-year Progression free survival (PFS) was 80.5% (70.6, 91.7). Patients receiving definitive intent PBT had lower but nonsignificant PFS (73.3% vs. 83.8%, p-0.075). Advanced T-staging and positive margins did not have worsened PFS. Overall survival at 3 years was 89.2% (81.4, 97.8). Acute grade 3 toxicities occurred in 16 patients, the most common included the following: mucositis (n=5), oral pain (n=3), and dermatitis (n=5). Late grade 3 toxicity (n=2) included middle ear inflammation (n=1) and skin ulceration (n=1). There were no grade 4+ toxicities.</p><p><strong>Conclusion: </strong>PBT appears to be highly efficacious in providing LRC for patients with ACC including those patients treated with definitive intent. PBT toxicity was acceptable. Longer follow-up is needed.</p>","PeriodicalId":36923,"journal":{"name":"International Journal of Particle Therapy","volume":"20 ","pages":"101320"},"PeriodicalIF":2.0,"publicationDate":"2026-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13208104/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148044064","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biologically Effective Dose-Optimized Multi-Intensity-Modulated Proton Therapy: A Biologically Comparable Alternative to Proton Arc Therapy.","authors":"Nimita Shinde, Yanan Zhu, Wei Wang, Wangyao Li, Yuting Lin, Gregory N Gan, Christopher Lominska, Ronny Rotondo, Ronald C Chen, Hao Gao","doi":"10.1016/j.ijpt.2026.101321","DOIUrl":"10.1016/j.ijpt.2026.101321","url":null,"abstract":"<p><strong>Purpose: </strong>Proton spot-scanning arc therapy (ARC) is an emerging technique that can enhance high-dose conformity to targets compared with standard intensity-modulated proton therapy (IMPT). Although proton ARC is highly desirable, it is not yet clinically available. Multiple IMPT plans delivered over different fractions and optimized simultaneously provide a practical means to approximate ARC-plan quality. However, existing multiple IMPT approaches are not optimized to be biologically comparable to proton ARC because they neglect the fractionation effect during treatment planning. This work proposes a biologically optimized multiple IMPT (multi-IMPT) framework that achieves comparable performance to proton ARC in terms of the biologically effective dose (BED). This is achieved through direct optimization of BED by explicitly incorporating the fractionation effect during planning, thereby ensuring biological comparability between multi-IMPT and proton ARC treatments.</p><p><strong>Materials and methods: </strong>The proposed multi-IMPT method utilizes a different subset of limited number of beam angles in each fraction for dose delivery. Due to the different dose delivered to organs at risk (OAR) in each fraction, the BED delivered to OAR and the physical dose delivered to target is optimized in each fraction. The BED-based multi-IMPT inverse optimization problem is solved via the iterative convex relaxation method and the alternating direction method of multipliers. The effectiveness of the proposed multi-IMPT method is evaluated in terms of BED objectives in comparison with ARC and IMPT.</p><p><strong>Results: </strong>Multi-IMPT provided similar plan quality with ARC. For example, multi-IMPT provided better OAR sparing and slightly better target dose coverage for the prostate case; similar dose distribution for the lung case; slightly worse dose coverage for the brain case; better dose coverage but slightly higher BED in OAR for the head-and-neck case.</p><p><strong>Conclusion: </strong>A multi-IMPT approach is proposed that delivers ARC-comparable plan quality under the evaluated conditions in terms of BED.</p>","PeriodicalId":36923,"journal":{"name":"International Journal of Particle Therapy","volume":"20 ","pages":"101321"},"PeriodicalIF":2.0,"publicationDate":"2026-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13208107/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148044094","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Validation of the Effectiveness of Visual Feedback Systems in Respiratory Gating Carbon Ion Radiation Therapy.","authors":"Ren Umetani, Yuya Miyasaka, Hikaru Souda, Hongbo Chai, Miyu Ishizawa, Yasuhito Hagiwara, Takashi Kaneko, Yoshifumi Yamazawa, Hiraku Sato, Masashi Koto, Takeo Iwai","doi":"10.1016/j.ijpt.2026.101319","DOIUrl":"10.1016/j.ijpt.2026.101319","url":null,"abstract":"<p><strong>Background: </strong>This study aimed to evaluate the efficacy of respiratory-gated irradiation using visual feedback (VF) in carbon-ion radiotherapy (CIRT). Furthermore, in patients with liver cancer undergoing CIRT, the treatment times of treatments with and without VF (non-VF) were compared.</p><p><strong>Material and methods: </strong>Thirty-three patients with liver cancer were analyzed. VF system was applied in 10 patients with liver tumors. To evaluate the efficacy of VF, patients treated non-VF were selected as a control group. All treatments were performed under free-breathing conditions in both the VF and non-VF groups. For each VF patient, 1-3 candidate non-VF patients were identified by matching the CTV size and irradiation gate width (amplitude). From these candidates, 1 non-VF patient was selected as a matched control for each VF patient. The average treatment time for each VF patient was compared with that of the corresponding non-VF patient. The effect of the reduced treatment time for VF was calculated by comparing each VF patient with the corresponding non-VF patient. To quantify respiratory variability, the root mean square error and standard deviation were calculated.</p><p><strong>Results: </strong>The treatment time was reduced in 8 of 10 pairs. Further, in 6 of 8 pairs, the treatment time was reduced by more than 5 minutes when using VF compared with non-VF. The RMSE value was significantly reduced at 50% and 100% (<i>P</i> < .05). The RMSE value decreased by 28.2% in the VF compared with non-VF. VF was effective in improving respiratory waveform reproducibility in most pairs.</p><p><strong>Conclusion: </strong>The results suggest that VF contributes to a reduction in treatment time, indicating improved time efficiency during irradiation sessions. In addition, VF improves respiratory waveform reproducibility, which may contribute to enhanced treatment accuracy. Furthermore, shortening the treatment time may reduce the treatment burden on patients and improve overall treatment workflow.</p>","PeriodicalId":36923,"journal":{"name":"International Journal of Particle Therapy","volume":"20 ","pages":"101319"},"PeriodicalIF":2.0,"publicationDate":"2026-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13213793/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148057397","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of a Low-Energy Cyclotron-Based Proton Beam for Preclinical Radiobiological Studies.","authors":"Ana Rita C Teixeira, Sérgio J C Do Carmo, Sofia Silva, Catarina I G Pinto, Pedro Santos, Paulo Crespo, Joana Lencart, António Paulo, Célia M Gomes, Antero J Abrunhosa, Filipa Mendes, Francisco Alves","doi":"10.1016/j.ijpt.2026.101318","DOIUrl":"10.1016/j.ijpt.2026.101318","url":null,"abstract":"<p><strong>Purpose: </strong>Proton therapy is considered an attractive alternative to conventional radiotherapy in oncology, as its dose-depth curve favors tumor control while minimizing the risk of radiation-induced side effects in healthy tissue. Preclinical investigation into proton Relative Biological Effectiveness (RBE) is imperative to improve the current clinical RBE standard and subsequently optimize therapeutic efficacy.</p><p><strong>Materials and methods: </strong>A low-energy cyclotron-based proton irradiation set-up for <i>in vitro</i> research was optimized at ICNAS-University of Coimbra. The system dosimetry was assessed using a calibration curve from a standard radiotherapy linear accelerator applied to proton-irradiated Gafchromic EBT4 films while recording integrated beam charge in real time. Pulsed dose rate measurements were performed by determination of target exposure time. As proof of concept, glioblastoma cell lines (U373 and U87) were subjected to proton irradiation for quantification of cell survival and DNA damage.</p><p><strong>Results: </strong>Homogeneous dose profiles were achieved on a 21 mm-diameter circular area at the target region for an incident proton energy of 14 MeV. A linear relation was found between proton dose at the target and integrated beam charge for pulsed dose rates from 10.8 to 16.2 Gy/s and a proton flux of ∼ 10⁷ protons/(s <math><mo>∙</mo></math> cm²). Proton irradiation of U373 cells yielded effects on cell survival comparable to kilovoltage X-ray exposure. U87 cells exhibited unrepaired DNA damage following proton exposure.</p><p><strong>Conclusion: </strong>A cyclotron-based pulsed proton beam was successfully optimized for <i>in vitro</i> radiobiological research, as evidenced by the first irradiation studies for evaluation of cell survival and DNA damage in glioblastoma cellular models.</p>","PeriodicalId":36923,"journal":{"name":"International Journal of Particle Therapy","volume":"20 ","pages":"101318"},"PeriodicalIF":2.0,"publicationDate":"2026-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13156708/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147869641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Emerging Outcome Trends From Proton Therapy for Pediatric CNS Tumors: A Systematic Review.","authors":"Jasper Greenland, Jake Kendrick, Martin A Ebert, Milad Mirzaei, Rohen White, Joshua Dass, Adriano Polpo, Pejman Rowshanfarzad","doi":"10.1016/j.ijpt.2026.101317","DOIUrl":"10.1016/j.ijpt.2026.101317","url":null,"abstract":"<p><strong>Purpose: </strong>This systematic review aims to provide a summary of outcomes of pediatric brain tumor patients treated with proton therapy (PT). Outcomes focused on include long-term efficacy and late toxicities. This study provides an analysis of survival, disease control, and safety outcomes across major pediatric brain tumor histologies to support contemporary clinical decision-making.</p><p><strong>Methods: </strong>A literature search was conducted across PubMed, Scopus, and Web of Science to identify studies reporting overall survival (OS), progression-free survival (PFS), local control (LC), or late toxicity in patients under 21 years with brain tumors treated with PT. Weighted linear regression was performed on survival outcomes modeling trends over post-treatment follow-up. Safety outcomes were qualitatively assessed based on histology and pooled where possible to facilitate cross-study comparison.</p><p><strong>Results: </strong>Seventy-seven studies were included, with 40 reporting on OS following PT in a total of 3798 patients. Statistically significant time-dependent models were obtained for medulloblastoma (PFS: <i>P</i> = .0018), ependymoma (OS: <i>P</i> = .0002, PFS: <i>P</i> = .0006, LC: <i>P</i> = .001), base of skull (BOS) chordoma (OS: <i>P</i> = .0498), and the mixed histology group (OS: <i>P</i> = .028), with trends observed in other histologies. LGG and craniopharyngioma demonstrated high survival, showing over 95% OS up to 10 years after treatment. Toxicity outcomes revealed common late toxicities, including endocrinopathies (ranging from 11.7% in ependymoma to 94% in craniopharyngioma), vasculopathy (1%: LGG - 36%: craniopharyngioma), hearing loss (4%: ependymoma - 26.3%: medulloblastoma), and neurocognitive decline (no significant decline: LGG - 1.5 points annual decline: medulloblastoma), with wide variations in incidence across histology reflecting differences in tumor location and treatment burden.</p><p><strong>Conclusion: </strong>Statistically significant trends in medulloblastoma, ependymoma, and BOS chordoma were identified, along with consistent outcomes in LGG and craniopharyngioma outcomes. Together, these findings provide clinicians with clearer expectations of prognosis following PT and establish reference benchmarks that can inform treatment planning, counsel families, and serve as a comparative foundation for future clinical research.</p>","PeriodicalId":36923,"journal":{"name":"International Journal of Particle Therapy","volume":"20 ","pages":"101317"},"PeriodicalIF":2.0,"publicationDate":"2026-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13202250/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148044096","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Robust Four-Field and Arc LET-Optimized Proton Prostate Cancer Treatment Plans With Urethral Sparing.","authors":"Michael Vieceli, Jiyeon Park, Mo Saki, Hardev Grewal, Nancy P Mendenhall, Perry Johnson, Mark Artz","doi":"10.1016/j.ijpt.2026.101316","DOIUrl":"10.1016/j.ijpt.2026.101316","url":null,"abstract":"<p><strong>Purpose: </strong>To create LET-optimized pencil beam scanning proton prostate cancer treatment plans with clinically acceptable range robustness and urethral sparing.</p><p><strong>Methods: </strong>Two-beam, four-beam, and arc LET-optimized treatment plans were created for a prostate cancer patient with varying levels of robustness to evaluate LET_d and several performance metrics. Urethral sparing was incorporated by de-escalating the physical dose to the urethra while maintaining high LET_d to prevent underdosing the periurethral prostate by merit of its lower <math><mrow><mi>α</mi> <mo>/</mo> <mi>β</mi></mrow> </math> . Four-beam and arc plans were created with a targeted robustness level for 12 patients along with reference SFO plans, and statistical comparisons were performed on clinical target volume prostate and seminal vesicles minus urethra (CTV PSV_-U) mean LET_d, target volume and organs at risk (OAR) relative biological effectiveness (RBE)-doses, minimum average RBE-doses, target-to-OAR dose ratios (TODRs), and OAR volumes receiving at least 80% of the CTV PSV D95 dose (V80%).</p><p><strong>Results: </strong>A tradeoff between robustness and high LET_d was demonstrated. Statistically significant differences in LET_d were found, with 2.5 keV/µm in SFO plans, 3.3 keV/µm in arc plans, and 3.5 keV/µm in four-beam plans. Statistically significant increases in CTV PSV_-U D95 RBE-dose resulted in 6.3%-8.1% increases in four-beam plans over SFO. High LET_d in the periurethral prostate prevented underdosage with urethral sparing. V80%s were statistically decreased in four-beam and most arc comparisons relative to SFO. While increased TODRs were demonstrated in a test patient, lack of statistical significance (or superiority in SFO over arc in the case of the rectum) in the 12 patient cohort occurred due to some patients already having low OAR RBE-doses in SFO plans, which could be addressed with additional optimization objectives at lower doses.</p><p><strong>Conclusion: </strong>LET-optimized treatment plans were created with high LET_d and clinically acceptable robustness with the potential to increase the therapeutic ratio and implemented urethral sparing without underdosing the periurethral prostate.</p>","PeriodicalId":36923,"journal":{"name":"International Journal of Particle Therapy","volume":"20 ","pages":"101316"},"PeriodicalIF":2.0,"publicationDate":"2026-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13127624/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147821886","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Particle Therapy Co-Operative Group Consensus Statement on Reirradiation With Proton Therapy for Prostate Cancer.","authors":"Shaakir Hasan, Xinglei Shen, Huan Giap, Sagar Patel, Christian Hyde, Curtiland Deville, James Gray, Charles B Simone, Nancy P Mendenhall, Seungtaek Choi, Curtis M Bryant","doi":"10.1016/j.ijpt.2026.101314","DOIUrl":"10.1016/j.ijpt.2026.101314","url":null,"abstract":"","PeriodicalId":36923,"journal":{"name":"International Journal of Particle Therapy","volume":"20 ","pages":"101314"},"PeriodicalIF":2.0,"publicationDate":"2026-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13099512/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147783953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phenomenological Study of Intra-Spill Break Spots in Dose-Driven Continuous Scanning Proton Therapy.","authors":"Clifford Ghee Ann Chua, Wilson Han Yi Lim, Kang Hao Lee, Kah Seng Lew, Masashi Yagi, Wei Yang Calvin Koh, Andrew Wibawa, Zubin Master, Wen Siang Lew, James Cheow Lei Lee, Sung Yong Park, Hong Qi Tan","doi":"10.1016/j.ijpt.2026.101315","DOIUrl":"10.1016/j.ijpt.2026.101315","url":null,"abstract":"&lt;p&gt;&lt;strong&gt;Purpose: &lt;/strong&gt;Dose Driven Continuous Scanning proton therapy offers reduced beam delivery time compared to discrete spot scanning but requires accurate characterization of temporal beam parameters for precise dose calculation. This study quantified rise time ( &lt;math&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;t&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mi&gt;rise&lt;/mi&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/math&gt; ) and plateau beam current ( &lt;math&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;I&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt; &lt;mo&gt;,&lt;/mo&gt; &lt;mi&gt;measured&lt;/mi&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/math&gt; ) variations across a complete spill cycle and assessed their impact on average beam current ( &lt;math&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;I&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mi&gt;avg&lt;/mi&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/math&gt; ) per spot.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Methods: &lt;/strong&gt;Beam current measurements were performed using a CROSSmini 2D detector array at 50 μs temporal resolution across 3 proton energies (70.2, 150.2, and 228.7 MeV) and 3 nominal beam currents (8, 14, and 20 MU/s) with break points implemented at every spot. Piecewise function fitting was applied to extract &lt;math&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;t&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mi&gt;rise&lt;/mi&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/math&gt; and &lt;math&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;I&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt; &lt;mo&gt;,&lt;/mo&gt; &lt;mi&gt;measured&lt;/mi&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/math&gt; parameters for each spot across complete spill durations. Sensitivity analysis was conducted using partial derivatives and experimental validation to quantify the relative impact of the temporal parameter variations on &lt;math&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;I&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mi&gt;avg&lt;/mi&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/math&gt; . Moving averages over 20-spot windows were calculated to characterize intra-spill parameter changes.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;&lt;math&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;I&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt; &lt;mo&gt;,&lt;/mo&gt; &lt;mi&gt;measured&lt;/mi&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/math&gt; observed a decreasing trend throughout spills before a steep terminal decline. Mean &lt;math&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;t&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mi&gt;rise&lt;/mi&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/math&gt; was 1.43 ± 0.71 ms across all conditions. Sensitivity analysis revealed &lt;math&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;I&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mi&gt;avg&lt;/mi&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/math&gt; exhibited substantially higher sensitivity to &lt;math&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;t&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mi&gt;rise&lt;/mi&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/math&gt; variations than &lt;math&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;I&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt; &lt;mo&gt;,&lt;/mo&gt; &lt;mi&gt;measured&lt;/mi&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/math&gt; changes, with &lt;math&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;t&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mi&gt;rise&lt;/mi&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/math&gt; variations producing up to 80% changes in &lt;math&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;I&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mi&gt;avg&lt;/mi&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/math&gt; compared to &lt;2% for &lt;math&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;I&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt; &lt;mo&gt;,&lt;/mo&gt; &lt;mi&gt;measured&lt;/mi&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/math&gt; variations across spill.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusion: &lt;/strong&gt;We have characterized &lt;math&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;t&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mi&gt;rise&lt;/mi&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/math&gt; and &lt;math&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;I&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt; &lt;mo&gt;,&lt;/mo&gt; &lt;mi&gt;measured&lt;/mi&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/math&gt; within a spill and the impact of the variation of these parameters on &lt;math&gt; &lt;msub&gt;","PeriodicalId":36923,"journal":{"name":"International Journal of Particle Therapy","volume":"20 ","pages":"101315"},"PeriodicalIF":2.0,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13138202/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147844034","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}