Advances in Radiation Oncology最新文献

{"title":"Safety and Efficacy of External Beam Radiation Therapy in Hepatocellular Carcinoma Patients Previously Treated With Yttrium 90 Transarterial Radioembolization","authors":"Kanokphorn Thonglert MD ,&nbsp;Joseph Tsai MD, PhD ,&nbsp;Wayne L. Monsky MD ,&nbsp;August C. Anderson MD ,&nbsp;Clemens Grassberger PhD ,&nbsp;Stephen R. Bowen PhD ,&nbsp;Matthew J. Nyflot PhD ,&nbsp;Yulun He PhD ,&nbsp;Peter Zaki MD ,&nbsp;Guy E. Johnson MD ,&nbsp;Smith Apisarnthanarax MD","doi":"10.1016/j.adro.2025.101984","DOIUrl":"10.1016/j.adro.2025.101984","url":null,"abstract":"<div><h3>Purpose</h3><div>Data on the safety and efficacy of external beam radiation therapy (EBRT) after yttrium 90 transarterial radioembolization (TARE) for hepatocellular carcinoma (HCC) are limited. We report our experience using EBRT to treat HCC patients previously treated with TARE.</div></div><div><h3>Methods and Materials</h3><div>We retrospectively analyzed 31 HCC patients who received EBRT following TARE. Eighteen (58%) were treated with photon therapy, and 13 (42%) with proton therapy. Eighteen patients (58%) had been previously treated with TARE within the EBRT-treated lesion, with a median total dose of 72 mCi (range, 49-272). Twenty-one patients (68%) had prior TARE outside the EBRT zone, with a median total dose of 84 mCi (range, 21-330). Toxicities and survival outcomes were analyzed.</div></div><div><h3>Results</h3><div>The number of prior TARE treatments ranged from 1 to 5: 14 patients (45%) received 1, and 17 (55%) received 2 or more. Indications for EBRT included incomplete TARE response (n = 2), technical TARE limitations (n = 25), and other reasons (n = 4). The median tumor size was 3.8 cm (range, 1.6-19.4). Most patients (87%) had a Child-Pugh (CP)-A score. With a median follow-up of 30 months, the 2-year progression-free survival and overall survival rates were 18% and 43%, respectively. The 2-year cumulative incidence of local failure was 7%. CP+2 progression was observed in 4 patients (13%). There was no significant difference in local failure or CP+2 rates based on the EBRT target location relative to prior TARE. Grade 3+ biliary complications occurred in 3 patients (10%): 2 biloma and 1 biliary stricture. All 3 patients had received at least 2 prior TARE treatments that overlapped with the area treated with EBRT and had tumors located near the central bile duct.</div></div><div><h3>Conclusions</h3><div>EBRT for HCC patients previously treated with yttrium 90 is feasible and offers excellent local control. Liver dysfunction and biliary toxicities are potential complications and should be weighed against the clinical benefits.</div></div>","PeriodicalId":7390,"journal":{"name":"Advances in Radiation Oncology","volume":"11 3","pages":"Article 101984"},"PeriodicalIF":2.7,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146177131","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Low Incidence of New-Onset Hypopituitarism After High-Precision Stereotactic Radiation Therapy of Sellar and Perisellar Lesions","authors":"Alexander Heer MD ,&nbsp;Malte Schneider MD ,&nbsp;Jan P. Boström MD ,&nbsp;Michael Pinkawa MD ,&nbsp;Attila Kovács MD ,&nbsp;Johannes Weller MD ,&nbsp;Jenny Bischoff MD ,&nbsp;Charlotte M. Fries MD ,&nbsp;Azize Boström MD ,&nbsp;Wiebke K. Fenske MD","doi":"10.1016/j.adro.2025.101933","DOIUrl":"10.1016/j.adro.2025.101933","url":null,"abstract":"<div><h3>Purpose</h3><div>Radiation therapy-induced hypopituitarism (RIH) is a common complication of radiation therapy, even if the pituitary gland is not the primary target but lies within the irradiation field. This study aimed to investigate the impact of high-precision radiation therapy for benign sellar and perisellar tumors, using radiosurgery or fractionated/hypofractionated stereotactic radiation therapy with the Novalis System (Brainlab), on functional pituitary integrity.</div></div><div><h3>Methods and Materials</h3><div>Fifty-six patients who underwent stereotactic radiation therapy for meningiomas of the sellar or perisellar region of the skull base (n = 36) or pituitary adenomas (n = 20) were recruited between 2013 and 2021 at a single radiooncologic clinic. Fractionated stereotactic radiation therapy was the main irradiation technique (n = 42), followed by hypofractionated stereotactic radiation therapy (n = 4) and stereotactic radiosurgery (n = 10). Irradiation data were assessed retrospectively, and radiation exposure to the pituitary was measured by dose-volume histograms. Each patient received an endocrine diagnostic workup, including a comprehensive functional pituitary analysis.</div></div><div><h3>Results</h3><div>The median age was 57 years (IQR, 50-63 years), and 42 of 56 patients (75%) were women. RIH was present in 10.7% (n = 6) of patients after a median follow-up of 83.5 months. Gonadotroph function was affected in 7.1% (n = 4) of patients, followed by corticotroph, thyreotroph, somatotroph, and lactotroph function, each at 1.8% (n = 1). Only 1 patient received hormonal replacement for RIH at the study visit.</div></div><div><h3>Conclusions</h3><div>Awareness of radiation therapy-induced damage to the pituitary gland is essential in the follow-up after radiation therapy of the surrounding structures of the hypothalamic-pituitary axis. High-precision fractionated stereotactic radiation therapy holds a low risk of RIH after irradiation of benign lesions of the sellar and perisellar region.</div></div>","PeriodicalId":7390,"journal":{"name":"Advances in Radiation Oncology","volume":"11 3","pages":"Article 101933"},"PeriodicalIF":2.7,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145973880","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In Regard to Prabhu et al","authors":"Alexander S. Marwaha DO ,&nbsp;Matthew J. Shepard MD ,&nbsp;Rodney E. Wegner MD","doi":"10.1016/j.adro.2025.101944","DOIUrl":"10.1016/j.adro.2025.101944","url":null,"abstract":"","PeriodicalId":7390,"journal":{"name":"Advances in Radiation Oncology","volume":"11 3","pages":"Article 101944"},"PeriodicalIF":2.7,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147448887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Is Ultrahigh Dose Rate Critical for the Effectiveness of Microbeam Radiation Therapy in a Broad-Beam Combined Treatment?","authors":"Elette Engels PhD ,&nbsp;Helen B. Forrester PhD ,&nbsp;Verdiana Trappetti PhD ,&nbsp;Kellie Mouchemore PhD ,&nbsp;Mitzi Klein VMD ,&nbsp;Alice H. Sprung ,&nbsp;Kirsty Brunt ,&nbsp;Micah J. Barnes PhD ,&nbsp;Matthew Cameron PhD ,&nbsp;Vincent de Rover BSc ,&nbsp;Bettina de Breuyn Dietler BSc ,&nbsp;Anatoly B. Rosenfeld PhD ,&nbsp;Michael L.F. Lerch PhD ,&nbsp;Robin L. Anderson PhD ,&nbsp;Olga A. Martin PhD ,&nbsp;Valentin G. Djonov MD","doi":"10.1016/j.adro.2025.101949","DOIUrl":"10.1016/j.adro.2025.101949","url":null,"abstract":"<div><h3>Purpose</h3><div>The superior therapeutic index of preclinical synchrotron microbeam radiation therapy (MRT) over conventional broad-beam (BB) radiation therapy (RT) has been clearly established. Published data demonstrate that a combination of 1 MRT session with 2 consecutive daily BB-RT sessions effectively controls the primary tumor and triggers an antitumor immune response. Here, we aimed to establish whether an ultrahigh dose rate of MRT, available exclusively on the synchrotron, is essential for effective treatment of murine triple-negative mammary carcinoma.</div></div><div><h3>Methods and Materials</h3><div>The in vitro response of mammary tumor cells was investigated using a clonogenic survival assay at different MRT dose rates (∼1000, 100, or 10 Gy/s). The in vivo tumor responses at the same dose rates, with an MRT/BB/BB treatment schedule, were evaluated by measuring tumor volume and the induced immune response. Animal survival and normal skin reactions were also assessed.</div></div><div><h3>Results</h3><div>Clonogenic survival decreased with decreasing MRT dose rate, with most cell sparing at the highest dose rate (1000 Gy/s), indicating that lower dose rates could be more effective against tumors. However, no significant differences in in vivo tumor growth delay were observed in response to dose-rate variations. Decreased infiltration of irradiated tumors with leucocytes and their subpopulations was observed at the lower dose rates, including decreased expression of immune checkpoints PD-1/PD-L1 and prognostic marker CD103, which could impact the overall tumor response in vivo. The higher dose rates were associated with increased antitumor immunity. Early euthanasia of mice, as dictated by ethical endpoints, prevented long-term observation of differences in animal survival. Skin toxicity in the vicinity of irradiated tumors was mild and developed later at the highest MRT dose rate. Overall, MRT at 10 to 1000 Gy/s was tolerated similarly, despite dramatic changes in the dose rate.</div></div><div><h3>Conclusions</h3><div>These findings are promising for the clinical translation of MRT in combination with conventional RT, using emerging compact x-ray MRT sources with dose rates lower than those delivered by synchrotron sources.</div></div>","PeriodicalId":7390,"journal":{"name":"Advances in Radiation Oncology","volume":"11 2","pages":"Article 101949"},"PeriodicalIF":2.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145735320","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Comparative, Multiobserver Analysis of Nodal Contouring Methods in Pelvic Online Cone Beam-Based Adaptive Radiation Therapy","authors":"Ethan Wang BSA ,&nbsp;Michael Dohopolski MD ,&nbsp;Allen Yen MD,&nbsp;Julia Jiazhen Shi BS,&nbsp;Brian Hrycushko PhD,&nbsp;David Parsons PhD,&nbsp;Yulun Liu PhD,&nbsp;Zohaib Iqbal PhD,&nbsp;Kevin Albuquerque MD","doi":"10.1016/j.adro.2025.101959","DOIUrl":"10.1016/j.adro.2025.101959","url":null,"abstract":"<div><h3>Purpose</h3><div>In online cone beam computed tomography (CBCT)-based adaptive radiation therapy (ART), nodal recontouring ensures sufficient nodal coverage by accounting for anatomic change but is uniquely challenging due to small target size and time pressure. This study evaluates the accuracy of rigid propagation versus artificial intelligence-guided deformation (AID) for nodal autosegmentation via comparison to nodal recontours delineated with unlimited time (ie, benchmark contours).</div></div><div><h3>Methods and Materials</h3><div>We analyzed 25 nodal structures from 16 patients receiving pelvic online CBCT-based ART with nodal boost. Nodal structure sampling was informed by an initial power analysis. For each structure, we obtained rigidly propagated and AID-generated contours in addition to 2 benchmark contours and the clinical contour used in adapted plan generation. We calculated dice similarity coefficient (DSC), false-positive dice, false-negative dice, and 95% Hausdorff distance (HD95) between clinical, propagated, and AID contours against benchmark pairs and DSC and HD95 between benchmark pairs. The failure rate of nonbenchmark contours relative to benchmark pairs was calculated as the proportion of contours with an HD95 &gt; 5 mm. We calculated the normalized D100, normalized D95, V100, and V95 of the adapted plan dose over all contours. Clinical tumor volume contours were used for all comparisons.</div></div><div><h3>Results</h3><div>Median DSC versus benchmark contours were 0.68 for rigidly propagated and 0.58 for AID contours. A significant difference in false-negative dice (<em>P</em> = .01, Cohen’s d 0.806) was identified in benchmark-to-propagated versus benchmark-to-AID comparison. The failure rate of rigidly propagated, AID, and clinical contours was 20%, 48%, and 28% respectively. The median DSC between benchmark contours was 0.75. No significant differences across dose metrics were identified between contour types.</div></div><div><h3>Conclusions</h3><div>Rigid propagation is superior to AID for initial contour generation in pelvic CBCT-based ART. Increased contouring time and image quality may improve contour quality and reduce interobserver variability but may be limited by the influence of individual contouring preferences.</div></div>","PeriodicalId":7390,"journal":{"name":"Advances in Radiation Oncology","volume":"11 2","pages":"Article 101959"},"PeriodicalIF":2.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145921702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydrogel Spacer Insertion Prior to Stereotactic Body Radiation Therapy to the Prostate: A Comparative Study","authors":"Myroslav Lutsyk MD ,&nbsp;Yosef Landman MD ,&nbsp;Eyal Fenig MD","doi":"10.1016/j.adro.2025.101966","DOIUrl":"10.1016/j.adro.2025.101966","url":null,"abstract":"<div><h3>Purpose</h3><div>The insertion of a hydrogel spacer between the rectum and prostate before stereotactic body radiation therapy (SBRT) for prostate cancer significantly reduces the radiation dose to the rectum. Despite the widespread use of this technique, clinical data remain sparse. The objective of this study was to investigate the clinical benefit of a hydrogel spacer in SBRT.</div></div><div><h3>Methods and Materials</h3><div>The database of a tertiary medical center was retrospectively searched for all patients with prostate cancer who underwent SBRT, with or without the insertion of a hydrogel spacer, between June 2013 and December 2018. The groups were compared for rectal and urinary toxicity (National Cancer Institute Common Terminology Criteria for Adverse Events v4) using the χ² test and <em>t</em> test. In addition, a subgroup analysis limited to patients receiving 37.5 or 40 Gy in 5 fractions was performed to account for the possible confounding effect of dose variability between the groups. Complications related to the procedure were also evaluated.</div></div><div><h3>Results</h3><div>The cohort included 308 patients who underwent SBRT with (n = 227) or without (n = 75) the insertion of a hydrogel spacer. Rates of grade 2 or higher rectal toxicity were 31 of 223 patients (13.9%) in the spacer group and 9 of 75 patients (12%) in the nonspacer group. Corresponding rates of urinary grade 2 toxicity were 58 of 223 patients (26%) and 14 of 75 patients (18.6%), respectively. Neither difference was statistically significant. Similar findings were observed in the subgroup analysis. Severe complications related to the procedure occurred in 5 of 227 cases (2.2%).</div></div><div><h3>Conclusions</h3><div>This study did not demonstrate a significant effect of hydrogel spacer insertion on reducing rectal or urinary toxicity in patients with prostate cancer undergoing SBRT. Given the dual consideration of questionable clinical benefit and the risk of debilitating complications, additional studies should be performed on the selective use of this procedure.</div></div>","PeriodicalId":7390,"journal":{"name":"Advances in Radiation Oncology","volume":"11 2","pages":"Article 101966"},"PeriodicalIF":2.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145788010","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preoperative Fractionated Stereotactic Radiosurgery for Brain Metastases: A Prospective Pilot Study at a Single Institution","authors":"Alexander Marwaha DO ,&nbsp;Matthew J. Shepard MD ,&nbsp;Yun Liang PhD ,&nbsp;Alexander Yu MD ,&nbsp;Stephen M. Karlovits MD ,&nbsp;Rodney E. Wegner MD","doi":"10.1016/j.adro.2025.101951","DOIUrl":"10.1016/j.adro.2025.101951","url":null,"abstract":"<div><h3>Purpose</h3><div>Brain metastases are a common occurrence in patients with advanced malignancy. Treatment ranges from surgical resection, stereotactic radiosurgery (SRS), whole-brain radiation therapy (WBRT), or some combination thereof. Traditionally, SRS has followed surgical resection to help reduce the risk of local recurrence. In recent years, interest has arisen in treating these patients in the preoperative setting to help reduce the risk of leptomeningeal disease (LMD) and radiation necrosis while preserving rates of local control. This prospective pilot study, originally planned as a phase 2 protocol, investigated the use of 3-fraction preoperative SRS on the Gamma Knife (GK) Icon with the goal of examining those outcomes.</div></div><div><h3>Methods and Materials</h3><div>Patients who had symptomatic and a limited number of brain metastases amenable to surgical resection were prospectively enrolled in this study. Patients were treated with fractionated SRS on the GK Icon to 24 to 27 Gy in 3 fractions followed by surgical resection within 2 weeks. Postoperative MRIs were obtained to assess the extent of resection. Patients were then followed up with standard-of-care MRIs every 3 months for the first 2 years. Rates of local control, distant brain failure, LMD, and delivery of WBRT were recorded on follow-up.</div></div><div><h3>Results</h3><div>Twenty patients were prospectively enrolled in the trial, and an additional 11 were treated off study using 1 to 3 fractions between April 2021 and June 2024. The median age was 64 (31-81), and 55% were females. Primary malignancies were mainly non-small cell lung cancer, melanoma, and esophageal cancer. The median prescription dose was 27 Gy (15-27 Gy) in 3 (1-3) fractions. Surgery was performed at a median of 1 day post-SRS (0-11). All available postoperative MRIs showed gross total resection. Median follow-up was 9 months. One patient experienced a local failure, yielding a 1-year local control rate of 95%. The rate of distant brain failure at 6 and 12 months was 38% at each time point. Three patients (9.6%) developed LMD in follow-up. Six patients ultimately received WBRT, yielding a 1-year WBRT-free survival of 78%. Overall survival at 1 year was 52%. There were no predictors of overall survival, local failure, or distant brain failure on Cox regression. Two patients experienced short-term toxicity, including grade 2 intracranial swelling and one grade 5 hemorrhagic stroke related to a hypertensive crisis. There was no recorded radionecrosis in follow-up.</div></div><div><h3>Conclusions</h3><div>Fractionated preoperative SRS appears to be safe and effective with high rates of local control and low rates of LMD and radionecrosis. Results of ongoing phase 3 studies directly comparing preoperative to postoperative SRS will help further define the appropriate sequencing of therapies.</div></div>","PeriodicalId":7390,"journal":{"name":"Advances in Radiation Oncology","volume":"11 2","pages":"Article 101951"},"PeriodicalIF":2.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145788097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of Local Medicare Guidance and Medicare Advantage Plans for Stereotactic Radiosurgery for Brain Metastases","authors":"Dominic LaBella MD,&nbsp;Eileen Battershall,&nbsp;Zachary J. Reitman MD, PhD,&nbsp;Scott R. Floyd MD, PhD,&nbsp;Eugene J. Vaios MD,&nbsp;John P. Kirkpatrick MD, PhD,&nbsp;Paul Sperduto MD,&nbsp;Trey C. Mullikin MD","doi":"10.1016/j.adro.2025.101974","DOIUrl":"10.1016/j.adro.2025.101974","url":null,"abstract":"<div><h3>Purpose</h3><div>Medicare Advantage operates under a capitated payment model, where Medicare Advantage Organizations (MAOs) must provide services that meet or exceed Medicare Parts A and B standards, ensuring actuarial equivalence. MAOs are mandated to base their coverage determinations on medical necessity, aligning with Medicare's national and local coverage determinations (LCD) policies.</div></div><div><h3>Methods and Materials</h3><div>This study evaluates coverage policies for stereotactic radiosurgery (SRS) for brain metastases (BM) across our institution's local LCD and various MAOs, including Cigna, Aetna, UnitedHealthcare, Humana, and Anthem. The CMS LCD L39553 (CMS) serves as the benchmark, deeming SRS medically necessary for new BM and repeat BM therapy if the patient has each of the following: good performance status (Karnofsky Performance Status ≥70 or Eastern Cooperative Oncology Group Performance Status 0-2), absence of leptomeningeal metastases, and no primary diagnosis of lymphoma, germ cell tumor, or small cell carcinoma. For repeat BM, CMS also requires stable extracranial disease and a life expectancy over 6 months. Additionally, SRS may be indicated for relapses in previously irradiated cranial fields to minimize normal tissue injury. Five MAO policies were reviewed, revealing alignment with LCD criteria in several areas but also presenting additional, sometimes more restrictive, requirements.</div></div><div><h3>Results</h3><div>For new BM, all MAOs required good performance status, with most also considering histology and absence of leptomeningeal metastases. Some MAOs introduced criteria like systemic therapy options, lesion number/volume, and BM size. For repeat BM, most MAOs required stable extracranial disease and occasionally considered life expectancy. Additional criteria included the number of BM over a year and postoperative SRS guidelines for lesion size and number.</div></div><div><h3>Conclusions</h3><div>Despite general concordance, the added criteria by MAOs could impose more stringent requirements than CMS, potentially resulting in coverage denials. It is important that MAO policies remain consistent with evidence-based guidelines to avoid disparities that could impact patient treatments.</div></div>","PeriodicalId":7390,"journal":{"name":"Advances in Radiation Oncology","volume":"11 2","pages":"Article 101974"},"PeriodicalIF":2.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145881111","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Accuracy of Photon Dose Calculation on Photon-Counting Computed Tomography—A Comparison Study Based on Virtual Monoenergetic and Electron Density (Rho) Images for Pancreatic Cases","authors":"Xin Wu MS ,&nbsp;Patrick Wohlfahrt PhD ,&nbsp;Jainil Shah PhD ,&nbsp;Ludovica Lofino MD ,&nbsp;Manisha Palta MD ,&nbsp;Qiuwen Wu PhD ,&nbsp;Q. Jackie Wu PhD ,&nbsp;Yang Sheng PhD","doi":"10.1016/j.adro.2025.101957","DOIUrl":"10.1016/j.adro.2025.101957","url":null,"abstract":"&lt;div&gt;&lt;h3&gt;Purpose&lt;/h3&gt;&lt;div&gt;Photon-counting computed tomography (PCCT) offers versatile anatomic information because of better energy discrimination and higher spatial resolution than conventional energy-integrating computed tomography (CT). With its rapid applications in diagnostic imaging, its potential within radiation oncology remains largely unexplored. Successful radiation therapy (RT) relies on both high-quality images to delineate tumor volume and accurate physical information of the anatomy for dose calculation. Specific to RT, dose calculation stands as a pivotal component in the process of treatment planning. This proof-of-concept study aimed to assess the accuracy of dose calculation and build the benchmark using PCCT images from a clinically operating NAEOTOM Alpha PCCT scanner from Siemens Healthineers.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Methods and Materials&lt;/h3&gt;&lt;div&gt;A total of 29 patients receiving abdominal contrast-enhanced PCCT scans were included in this study with institutional review board approval. The following 2 sets of reconstructed images were selected for this study: (1) virtual monoenergetic images (VMIs) of 70 keV, which resembles the conventional CT image at 120 kVp, and (2) electron density (Rho) images derived from PCCT, which provides direct physical information for photon dose calculation. In addition to the default Hounsfield look-up table (HLUT) implemented in a treatment planning system, which is suitable for conventional CT images, a specific HLUT converting 70 keV VMI CT numbers to relative electron density was established following the consensus guidelines. Patient’s organs were contoured using a deep-learning-based autosegmentation model in syngo.via RT Image Suite from Siemens Healthineers. An elective and a gross tumor volume were simulated in the pancreatic region for treatment planning within this study. All patients were planned with a 9-field intensity modulated RT with simultaneous integral boost regimen 25/33 Gy using an in-house deep-learning-based autoplanning model. Planning guidelines followed the institutional pancreas stereotactic body RT protocol. Eleven dose-volume histogram (DVH) metrics were included for comparison of 3-dose calculation approaches (conventional, 70 keV VMI and Rho).&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Results&lt;/h3&gt;&lt;div&gt;The results revealed minimal dosimetry differences between 70 keV VMI and Rho images, with DVH metric percentage differences predominantly within 1% range (max: -1.60%) and 3-dimensional gamma analysis (1 mm/1%) pass rate &gt;98% for most cases. The patient with the largest differences showed an average DVH metric difference of -1.32% and 3-dimensional gamma pass rate of 94.82%. Overall isodose distribution remained similar between 2 images for each patient. Dose calculation using the default HLUT in Eclipse showed DVH differences within a 1.5% range.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Conclusions&lt;/h3&gt;&lt;div&gt;The results demonstrated good agreement in dose calculation between 70 keV VMI and Rho images. For ","PeriodicalId":7390,"journal":{"name":"Advances in Radiation Oncology","volume":"11 2","pages":"Article 101957"},"PeriodicalIF":2.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145837442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Impact of Radiation Dose to Bowel on the Risk of Developing Gastrointestinal Toxicities When Treating Abdominopelvic Soft-Tissue Sarcomas With Preoperative Radiation Therapy","authors":"Alison Yoder MD ,&nbsp;Tucker Netherton PhD ,&nbsp;Xin Wang PhD ,&nbsp;Tze Lim PhD ,&nbsp;Catherine Wang PhD ,&nbsp;Dershan Luo PhD ,&nbsp;Congjun Wang PhD ,&nbsp;Sara Thrower PhD ,&nbsp;Callistus Nguyen PhD ,&nbsp;Heather Lyu MD ,&nbsp;Christopher Scally MD ,&nbsp;Christina Roland MD ,&nbsp;Devarati Mitra MD PhD ,&nbsp;Andrew Bishop MD ,&nbsp;Ahsan Farooqi MD PhD ,&nbsp;B Ashleigh Guadagnolo MD","doi":"10.1016/j.adro.2025.101953","DOIUrl":"10.1016/j.adro.2025.101953","url":null,"abstract":"<div><h3>Purpose</h3><div>Abdominopelvic soft-tissue sarcomas (AP-STS) are selectively treated with radiation therapy (RT) followed by surgery. We investigated dosimetric factors predictive of acute and long-term gastrointestinal (GI) toxicities in patients treated with preoperative RT for AP-STS.</div></div><div><h3>Methods and Materials</h3><div>We performed a retrospective cohort study of patients treated for nonmetastatic AP-STS with preoperative RT and surgery from 2005 to 2020. Individual loops of small and large bowel, as well as a “Bowel Bag” space, were autocontoured using a clinically validated deep learning-based approach (nnU-Net) and then manually reviewed. Chi-square or Fisher’s exact test was used to assess how bowel dosimetry related to the development of GI toxicities. In particular, the effect on GI toxicity of exceeding bowel constraints as defined in the consensus guidelines was evaluated. Recurrence outcomes were analyzed using the Kaplan-Meier method.</div></div><div><h3>Results</h3><div>We evaluated 76 patients with a median follow-up of 46 months (IQR, 42-50). Approximately half of the tumors were located in the retroperitoneal space (n = 39, 51%). A total of 60 patients (79%) presented with <em>de novo</em> disease, and 21% (n = 16) were recurrent presentations that had not received prior RT. Fourteen patients (18%) had a local recurrence alone, 23 (30%) a distant recurrence alone, and 3 (4%) combined local and distant recurrence. As a result of RT, 23 patients (30%) had acute grade 1 to 2 diarrhea, and 14 (18%) had grade 1 nausea. There were no acute grade 3 toxicities. Six patients (8%) had any long-term RT-related toxicity, including 1 small bowel obstruction. Patients were more likely to have an acute GI toxicity if bowel bag V45&gt;195 cm³ (<em>P</em> = .05).</div></div><div><h3>Conclusions</h3><div>Traditional RT volumetric bowel dose constraints are frequently exceeded, given the large size of AP-STS at presentation and the corresponding large RT volumes. Exceeding the conventional bowel dosimetric constraints should not dissuade the use of RT, but instead signal the need for aggressive prophylactic management of potential toxicities.</div></div>","PeriodicalId":7390,"journal":{"name":"Advances in Radiation Oncology","volume":"11 2","pages":"Article 101953"},"PeriodicalIF":2.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145735319","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}