International Journal of Radiation Oncology Biology Physics最新文献

{"title":"An Organized Approach to Ablative Radiation Therapy","authors":"Michael Chisam MD, Manisha Palta MD","doi":"10.1016/j.ijrobp.2024.12.040","DOIUrl":"10.1016/j.ijrobp.2024.12.040","url":null,"abstract":"","PeriodicalId":14215,"journal":{"name":"International Journal of Radiation Oncology Biology Physics","volume":"121 5","pages":"Pages 1100-1101"},"PeriodicalIF":6.4,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143608770","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In Regard to Sanford et al","authors":"Marco Lorenzo Bonù, Luca Triggiani, Andrea Guerini, Michela Buglione, Stefano Maria Magrini","doi":"10.1016/j.ijrobp.2024.12.025","DOIUrl":"10.1016/j.ijrobp.2024.12.025","url":null,"abstract":"","PeriodicalId":14215,"journal":{"name":"International Journal of Radiation Oncology Biology Physics","volume":"121 5","pages":"Pages 1396-1397"},"PeriodicalIF":6.4,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143611495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Long Term Results of a Phase II Study of Adjuvant Proton Radiotherapy for Node-Positive Cancer of the Uterus and Cervix: Proton Radiation for Uterine/Cervical Cancer.","authors":"Andrea L Russo, Nicolas Depauw, Nora K Horick, Jennifer Y Wo, Jacqueline A Nyamwanda, Fantine Giap, Leilana Ly, Marcela G Del Carmen, Annekathryn Goodman, Richard T Penson, Thomas F DeLaney, Anthony H Russell","doi":"10.1016/j.ijrobp.2025.03.010","DOIUrl":"https://doi.org/10.1016/j.ijrobp.2025.03.010","url":null,"abstract":"<p><strong>Purpose/objective(s): </strong>Patients with node-positive (LN+) uterine or cervical cancer often require post-operative radiation (RT) to the pelvis and para-aortic nodes. A prospective phase II study was conducted to evaluate the efficacy of proton beam RT for LN+ uterine or cervical cancer.</p><p><strong>Materials/methods: </strong>Patients with IIIC uterine and cervical cancer post hysterectomy and lymphadenectomy were eligible. Patients received 45 Gy(RBE) in 25 fractions with proton pencil beam scanning (PBS-PT). Primary endpoints included comparing dose volume histogram (DVH) and toxicity (CTCAE v4.02) between PBS-PT and IMRT or 3DCRT. Secondary endpoints included progression free survival (PFS), overall survival (OS), patterns of recurrence, and quality of life (QOL using FACT-En/Cx V4).</p><p><strong>Results: </strong>21 patients completed RT between 10/2013 and 10/2018. Median follow-up was 60.6 months (range, 11.2 - 68.8). There were 15 uterine and 6 cervical cancer patients. Four received pelvic and 17 received extended-field-RT. DVH comparisons showed significantly less volume treated with PBS-PT compared to 3D-CRT and IMRT for bowel, bone marrow, and kidney (all p<0.05) at all dose levels except V45 bladder and bowel. Acute and late grade 3 GI toxicity were 14 % and 4.7 %, respectively. There were no acute or late grade 3 GU toxicities. Acute and late grade 3 hematologic toxicities were 24 % and 4.7 %, respectively. There was one late grade 3 lymphedema. The 2- and 5- year PFS were 81 % (95 % CI, 56 %-92 %) and 76 % (95 % CI, 51 %-89 %). There were no in-field recurrences. The 2- and 5-year OS were 86 % (95 % CI, 62 %-95 %) and 80 % (95 % CI, 55 %-92 %). QOL increased significantly over time with average increase of 10.7 points from baseline to 5 years (95 % CI: 0.9 to 20.4, p=0.032).</p><p><strong>Conclusion: </strong>Compared to photon radiotherapy, PBS-PT treats significantly less normal tissue volume. PBS-PT appears effective in preventing local-regional recurrence in LN+ patients with minimal acute and late toxicity. QOL significantly improved from baseline to 5 years.</p>","PeriodicalId":14215,"journal":{"name":"International Journal of Radiation Oncology Biology Physics","volume":" ","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143633888","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Joining Forces to Advance Reirradiation: Establishing the Reirradiation Collaborative Group.","authors":"Charles S Mayo, Ane L Appelt, Kelly C Paradis, Laura A Dawson, Nicolaus Andratschke, Eliana M Vasquez Osorio, Søren M Bentzen, Ellen D Yorke, Andrew Jackson, Lawrence B Marks, Sue S Yom","doi":"10.1016/j.ijrobp.2025.01.038","DOIUrl":"10.1016/j.ijrobp.2025.01.038","url":null,"abstract":"","PeriodicalId":14215,"journal":{"name":"International Journal of Radiation Oncology Biology Physics","volume":" ","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143633885","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dosimetry and Toxicity Comparison of Three-Dimensional Conformal Radiation Therapy and Intensity Modulated Radiation Therapy in Locally Advanced Lung Cancer Across a Large Statewide Quality Collaborative.","authors":"Steven G Allen, Caitlin A Schonewolf, Matthew J Schipper, Huiying Maggie Yin, Peter A Paximadis, Larry L Kestin, Michael Dominello, Melissa Wilson, Martha M Matuszak, James A Hayman, Shruti Jolly","doi":"10.1016/j.ijrobp.2025.03.007","DOIUrl":"10.1016/j.ijrobp.2025.03.007","url":null,"abstract":"<p><strong>Purpose: </strong>Use of intensity modulated radiation therapy (IMRT) versus three-dimensional conformal external beam radiation therapy (3D-CRT) for definitive chemoradiation therapy (CRT) in locally advanced non-small cell lung cancer (LA-NSCLC) has been associated with decreased late pneumonitis, decreased high dose to the heart (itself associated with improved overall survival), and improved patient quality of life. In a statewide radiation oncology quality consortium, we sought to evaluate the impact of IMRT versus 3D-CRT treatment technique on dosimetry and toxicity.</p><p><strong>Methods and materials: </strong>From 2012 to 2022, 1746 LA-NSCLC patients meeting inclusion criteria underwent definitive RT (90% CRT) with either 3D-CRT (n = 313) or IMRT (n = 1433) and were enrolled in the Michigan Radiation Oncology Quality Consortium (MROQC) prospective, multicenter statewide initiative. Physician reported toxicity and patient-reported outcomes (PROs) were collected during treatment through 6 months after RT and compared by treatment technique. Inverse probability of treatment weighting (IPTW) was used to account for differences in prognostic factors between IMRT and 3D-CRT patients.</p><p><strong>Results: </strong>Compared with 3D-CRT patients, IMRT patients had significantly larger PTVs (median 386 cc vs 292 cc; P < .0001) and were more likely to have Stage IIIB disease (34.3% vs 23.0%; P < .0001). After adjustment using IPTW, treatment with IMRT compared with 3D-CRT reduced high dose to the lung (mean V30 Gy 17.9% vs 19.2%; P = .027) and heart (proportion with V40 Gy ≥ 20% 6.4% vs 15.3%; P < .0001). In logistic regression models using IPTW, through 6 months of early follow-up, there were no significant differences between 3D-CRT and IMRT in rates of grade 2+ acute esophagitis (odds ratio [OR] = 1.02; 95% CI, 0.73,1.42; P = .91) and grade 2+ early pneumonitis (OR = 1.62; 95% CI, 0.89, 2.96; P = .11) or in likelihood of a clinically significant decline in PROs.</p><p><strong>Conclusions: </strong>With late follow-up ongoing, this study supports the continued preferential use of IMRT over 3D-CRT for LA-NSCLC treatment due to improvements in heart and lung doses.</p>","PeriodicalId":14215,"journal":{"name":"International Journal of Radiation Oncology Biology Physics","volume":" ","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143615474","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ultrahypofractionation and Simultaneous Integrated Boost in Breast Cancer: Early Side Effects Analysis.","authors":"Maia Dzhugashvili, Ana Serradilla, Jaume Fernández-Ibiza, Graciela García, Kirill Matskov Malinochka, Lisellot Torres, Antonio Seral, José Begara, Daniela Gonsalves, Juan José De la Cruz Troca, Philip Poortmans, Felipe Couñago, Escarlata López","doi":"10.1016/j.ijrobp.2025.02.003","DOIUrl":"https://doi.org/10.1016/j.ijrobp.2025.02.003","url":null,"abstract":"<p><strong>Purpose: </strong>The FAST-Forward study paved the way for ultrahypofractionation (UHF) in breast cancer. We prospectively registered and analyzed our case series receiving UHF + simultaneous integrated boost (SIB) to further reduce the treatment to a total of 5 days. The study aimed to present the 6-month early side effects results of the first patients treated with this scheme in 16 radiation oncology centers in Spain.</p><p><strong>Methods and materials: </strong>A total of 242 breast cancer patients received adjuvant radiation therapy between April and December 2020. The median age was 61 years (interquartile range, 53-70). All patients underwent breast-conserving surgery. Chemotherapy (QT) was administered to 27.7%, and endocrine therapy to 85.1%. A SIB of 29 Gy was applied to 60.7% of the patients, while 39.3% did not have a boost indication. Breast radiation therapy (RT) with SIB to the tumor bed and regional node irradiation was done in 5.4 % of patients.</p><p><strong>Results: </strong>Most patients were treated with Volumetric modulated arc therapy (66.1%) and intensity modulated RT (30.6%). One patient received treatment by 3-dimensional techniques (0.4%) and 7 patients (2.9%) a combined intensity modulated RT-3-dimensional technique. Deep inspiration breath-hold was used in 16.9% of cases. At the end of treatment, erythema grade (G) 0 was presented in 56.1%, G1 in 43.1%, and G2 in 0.8%. G1 edema was observed in 14.6% and less than 1% had G2. After 6 months, 97% had G0 erythema, 3% G1, and 0% G2, while G1 edema was observed in 11.4% and G2 in 2.5%. No statistically significant impact on side effects was found for planning target volume breast and planning target volume boost volumes.</p><p><strong>Conclusions: </strong>UHF with SIB of 29 Gy to the tumor bed in patients with early-stage breast cancer is clinically feasible, safe, and free of an excess of early side effects. Further analysis of late toxicity is needed.</p>","PeriodicalId":14215,"journal":{"name":"International Journal of Radiation Oncology Biology Physics","volume":" ","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143605056","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Role of Neoadjuvant Chemoradiation Therapy for Resectable and Borderline Resectable Pancreatic Adenocarcinoma-A Systematic Review and Meta-Analysis.","authors":"Hsiao-Yu Wu, Hsiao-Hui Tsou, Long-Sheng Lu, Hsin-Lun Lee, Jeng Fong Chiou, Hui-Ju Ch'ang","doi":"10.1016/j.ijrobp.2025.02.037","DOIUrl":"10.1016/j.ijrobp.2025.02.037","url":null,"abstract":"<p><strong>Background: </strong>Randomized trials and meta-analyses have indicated longer survival with neoadjuvant than with adjuvant therapy in patients with resectable or borderline resectable (R/BR) pancreatic adenocarcinoma. Despite the efficacy of chemotherapy, the role of radiation therapy as an adjuvant or neoadjuvant treatment for patients with R/BR pancreatic adenocarcinoma remains unclear. In this systematic review and meta-analysis, we compared the benefits of additional chemoradiation therapy (CRT) to neoadjuvant chemotherapy (NAC) with NAC alone for R/BR pancreatic adenocarcinoma.</p><p><strong>Methods and materials: </strong>A systematic literature search was conducted on Embase, Web of Science, PubMed, Cochrane, and Google Scholar. Median overall survival (OS) was the primary endpoint. Secondary endpoints included disease-free survival (DFS), resection rate, and R0 resection rate.</p><p><strong>Results: </strong>This review and meta-analysis included 31 prospective studies, of which 9 were randomized trials. In these studies, 658 patients from 14 study arms received NAC alone and 912 patients from 19 study arms received both NAC and CRT (NAC-CRT). The pooled median OS was 25.55 months (95% CI, 21.59-30.24 months) for NAC alone and 17.55 months (95% CI, 16.47-18.70 months; P < .0001) for NAC-CRT. The pooled R0 resection rate was higher with NAC-CRT (83.43%) than with NAC (69.97%; P < .0001). No significant difference was observed in DFS or resection rate between the 2 groups. In patients who received 5 or more cycles of initial chemotherapy, NAC-CRT was associated with longer OS than NAC (23.30 vs 21.85 months; P = .856).</p><p><strong>Conclusions: </strong>NAC provides significantly longer OS than NAC-CRT to R/BR pancreatic adenocarcinoma. NAC-CRT is associated with a significantly improved R0 resection rate. This positive local effect of CRT can be translated to extended survival when 5 cycles or more of NAC are prescribed.</p>","PeriodicalId":14215,"journal":{"name":"International Journal of Radiation Oncology Biology Physics","volume":" ","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143615478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reirradiation Special Medical Physics Consultations: Lessons Learned From Nearly 3000 Courses of Treatment.","authors":"Kelly C Paradis, Charles Mayo, Charles K Matrosic, Joann I Prisciandaro, Benjamin S Rosen, Steven G Allen, Alex K Bryant, Enid Choi, Kyle Cuneo, Robert Dess, Alek Dragovic, Joseph R Evans, James A Hayman, Jason Hearn, Elizabeth M Jaworski, Shruti Jolly, Michelle M Kim, Theodore S Lawrence, Sean Miller, Grace Sun, Daniel R Wahl, Martha M Matuszak, Daniel T Chang","doi":"10.1016/j.ijrobp.2025.03.002","DOIUrl":"10.1016/j.ijrobp.2025.03.002","url":null,"abstract":"<p><strong>Purpose: </strong>Reirradiation (reRT) has become increasingly prevalent due to an aging population and advancements in cancer detection and treatment. However, the field is still lacking standardized dosimetric evaluation methods and reRT workflows, which leads to difficulty in correlating clinical outcomes with delivered dose. This study reports on the implementation and evolution of a standardized reRT workflow in the Department of Radiation Oncology at University of Michigan, describing insights gained from nearly 3000 external beam reirradiation courses delivered since 2017.</p><p><strong>Methods and materials: </strong>A systematic workflow for reRT special medical physics consultations (SMPCs) was established in 2017. Patient SMPC records from the past 7 years were reviewed, with an additional more in-depth review of the past 1 year, to report on course characteristics including treatment sites, where prior treatment was delivered (in-house vs an outside institution), whether institutional dose limits were met and the associate reasoning, time intervals between RT, the type of dose summation method used (rigid image registration-based vs point dose-based), as well as the evolution of this workflow.</p><p><strong>Results: </strong>Of the 2929 SMPCs conducted from 2017 to mid-2024, the most common treatment sites for reRT were the pelvis, brain, and thorax. About a third of patients had prior treatments at outside institutions. Of the 427 courses treated in the past year, institutional reirradiation dose limits were met in 82.2%. Rigid image registration was most successful for calculating composite dose in the brain (93.8% of cases) and least successful in the abdomen and pelvis (53.1% and 51.2%, respectively), and most reRT cases (80.3%) had a single prior course of treatment. Several updates were made to our institutional reRT dosimetric evaluation template, including increasing some time-dependent tissue recovery factors, adding and removing some OARs, and adding new point-based and volumetric dose objectives.</p><p><strong>Conclusions: </strong>On the basis of our 7 years of experience with nearly 3,000 courses of reRT, we highlight the critical need for standardized reirradiation workflows, improved tools for cumulative dose assessment, and standardized reporting. These efforts will facilitate cross-institutional data sharing to enhance data-driven clinical decision-making and improve patient outcomes in reRT. As the prevalence of reRT rises, these efforts are vital for advancing safe and effective cancer care.</p>","PeriodicalId":14215,"journal":{"name":"International Journal of Radiation Oncology Biology Physics","volume":" ","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143605045","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling the Effect of Daughter Migration on Dosimetry Estimates for [²²⁵Ac]Ac-DOTATATE.","authors":"Stephen Tronchin, Jake Forster, Kevin Hickson, Eva Bezak","doi":"10.1016/j.ijrobp.2025.03.004","DOIUrl":"10.1016/j.ijrobp.2025.03.004","url":null,"abstract":"<p><strong>Purpose: </strong>[²²⁵Ac]Ac-DOTATATE is a promising treatment option for patients with neuroendocrine tumors. A concern with ²²⁵Ac is that the decay energy can break the bond to the targeting vehicle, producing free daughter radionuclides in the body. Daughter migration is generally not considered in clinical dosimetry, and therefore its effect needs to be studied.</p><p><strong>Methods and materials: </strong>A compartment model for ²²⁵Ac and its daughters was developed, where each daughter isotope was assigned unique transfer coefficients. The model was applied to [²²⁵Ac]Ac-DOTATATE. Computer simulations were performed in Python for 2 scenarios: (1) the daughters decay at the site of [²²⁵Ac]Ac-DOTATATE decay; and (2) the daughters have unique biokinetics, where each decay of [²²⁵Ac]Ac-DOTATATE releases ²²¹Fr off the DOTATATE peptide. Two extreme cases concerning intracellular degradation of [²²⁵Ac]Ac-DOTATATE were also examined: 1 in which it remains intact inside the tumor cells, and 1 with complete degradation followed by free ²²⁵Ac released back to plasma. Normal organ and tumor absorbed doses were determined in each case. In addition, the model-calculated cumulated activities of ²²¹Fr and ²¹³Bi were compared with recent measurements from a clinical trial.</p><p><strong>Results: </strong>When modeling the unique daughter kinetics, the average absorbed dose to the kidneys and tumor was 517 (95% CI, 413-622) and 577 (95% CI, 134-1020) mGy/MBq, respectively, with daughter migration resulting in an average increase in the kidney dose of 10.2% (95% CI, 7.9%-12.5%), and an average decrease in the tumor dose of 22.9% (95% CI, 16.3%-29.4%). The model scenario including free ²²⁵Ac showed improved agreement with clinical trial data, specifically for the liver, suggesting a fraction of free ²²⁵Ac is produced in patients following the administration of [²²⁵Ac]Ac-DOTATATE.</p><p><strong>Conclusions: </strong>When performing dosimetry for [²²⁵Ac]Ac-DOTATATE, our study found that if daughter migration is ignored, the kidney dose is underestimated by ∼10%, and the tumor dose is overestimated by ∼23%. For accurate dosimetry, daughter biokinetics should be considered.</p>","PeriodicalId":14215,"journal":{"name":"International Journal of Radiation Oncology Biology Physics","volume":" ","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143605040","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Direct-to-Treatment Adaptive Radiation Therapy: Live Planning of Spine Metastases Using Novel Cone Beam Computed Tomography.","authors":"K Maiti McGrath, Robert Lee MacDonald, James L Robar, Amanda Cherpak","doi":"10.1016/j.ijrobp.2025.02.045","DOIUrl":"10.1016/j.ijrobp.2025.02.045","url":null,"abstract":"<p><strong>Purpose: </strong>Cone beam computed tomography (CBCT)-based online adaptive radiation therapy is carried out using a synthetic CT (sCT) created through deformable registration between the patient-specific fan-beam CT, fan-beam computed tomography (FBCT), and daily CBCT. Ethos 2.0 allows for plan calculation directly on HyperSight CBCT and uses artificial intelligence-informed tools for daily contouring without the use of a priori information. This breaks an important link between daily adaptive sessions and initial reference plan preparation. This study explores adaptive radiation therapy for spine metastases without prior patient-specific imaging or treatment planning. We hypothesize that adaptive plans can be created when patient-specific positioning and anatomy is incorporated only once the patient has arrived at the treatment unit.</p><p><strong>Methods and materials: </strong>An Ethos 2.0 emulator was used to create initial reference plans on 10 patient-specific FBCTs. Reference plans were also created using FBCTs of (1) a library patient with clinically acceptable contours and (2) a water-equivalent phantom with placeholder contours. Adaptive sessions were simulated for each patient using the 3 different starting points. Resulting adaptive plans were compared with determine the significance of patient-specific information prior to the start of treatment.</p><p><strong>Results: </strong>The library patient and phantom reference plans did not generate adaptive plans that differed significantly from the standard workflow for all clinical constraints for target coverage and organ at risk sparing (P > .2). Gamma comparison between the 3 adaptive plans for each patient (3%/3 mm) demonstrated overall similarity of dose distributions (pass rate > 95%), for all but 2 cases. Failures occurred mainly in low-dose regions, highlighting difference in fluence used to achieve the same clinical goals.</p><p><strong>Conclusions: </strong>This study confirmed feasibility of a procedure for treatment of spine metastases that does not rely on previously acquired patient-specific imaging, contours or plan. Reference-free direct-to-treatment workflows are possible and can condense a multistep process to a single location with dedicated resources.</p>","PeriodicalId":14215,"journal":{"name":"International Journal of Radiation Oncology Biology Physics","volume":" ","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143605035","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}