Brachytherapy最新文献

{"title":"Twice daily template-based interstitial brachytherapy for gynecologic cancers: What is the optimal dose?","authors":"Ria Mulherkar ,&nbsp;David Grimm ,&nbsp;Paniti Sukumvanich ,&nbsp;Madeleine Courtney-Brooks ,&nbsp;Michelle Boisen ,&nbsp;Jessica Berger ,&nbsp;Sarah Taylor ,&nbsp;Jamie Lesnock ,&nbsp;Shannon Rush ,&nbsp;Allison Garrett ,&nbsp;Haider Mahdi ,&nbsp;John Comerci ,&nbsp;Alexander Olaiwaye ,&nbsp;Robert Edwards ,&nbsp;Elangovan Doraisamy ,&nbsp;Michael Hajduk ,&nbsp;Christopher J. Houser ,&nbsp;Hayeon Kim ,&nbsp;John Austin Vargo IV","doi":"10.1016/j.brachy.2025.03.002","DOIUrl":"10.1016/j.brachy.2025.03.002","url":null,"abstract":"<div><h3>INTRODUCTION</h3><div>Several factors of template-based interstitial brachytherapy in gynecologic cancers, including large tumor size, invasion into adjacent organs or fistula, dose heterogeneity, and twice daily fractionation cause inherent dose-escalation effects, potentially increasing toxicity. This study reports a single-institutional dose escalation experience in twice daily template-based interstitial brachytherapy treatments to demonstrate tumor control and toxicity outcomes, with the hypothesis that with image-based planning dose-escalation with interstitial brachytherapy is safe and efficacious.</div></div><div><h3>METHODS</h3><div>Patients treated with template-based interstitial brachytherapy at our institution from 2006 to 2022 were identified. Over time, HDR brachytherapy boost dose at our institution has been dose-escalated from 18.75 Gy in 5 fractions to 27.5 Gy in 5 fractions. Local control and survival outcomes were analyzed using the Kaplan–Meier method and log-rank test to compare between groups. Formal tumor control probability (TCP) analysis was performed using logistic dose-response modeling.</div></div><div><h3>RESULTS</h3><div>214 patients were identified with median follow-up of 28.1 months (IQR 8.2–58.7). Total HDR dose correlated significantly with local and locoregional control when analyzed as a continuous variable, and when dichotomized around median dose of 25 Gy (<em>p</em> = 0.024). TCP analysis showed a dose-response effect between HR CTV D90 and local control in the entire cohort, and separately in cervical and vaginal cancer subsets. The actuarial 5-year incidence of grade 3 or worse toxicity was 6.1%, and there was no significant association between toxicity and total HDR dose or HR CTV D90.</div></div><div><h3>CONCLUSION</h3><div>In patient treated with twice-daily template-based interstitial brachytherapy for gynecologic cancers brachytherapy dose correlates with local control with no significant association between brachytherapy dose and toxicity, thus suggesting room for dose-escalation.</div></div>","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":"24 4","pages":"Pages 495-503"},"PeriodicalIF":1.7,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144047227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A dosimetric evaluation of ureteric doses with and without ureter as avoidance organ in patients treated with MR hybrid brachytherapy for cervical cancer","authors":"Harjot Kaur Bajwa ,&nbsp;Sushil Beriwal ,&nbsp;Rajesh Natte ,&nbsp;Racharla Chandra Kumar ,&nbsp;Rampally Kumar ,&nbsp;Suresh Chaudhari","doi":"10.1016/j.brachy.2025.02.007","DOIUrl":"10.1016/j.brachy.2025.02.007","url":null,"abstract":"<div><h3>PURPOSE</h3><div>Ureteric stenosis is a known complication with radiotherapy with studies showing correlation of ureteric dose with stenosis. This study was done to assess the dose delivered to the ureters with and without ureter as avoidance organ in cervical cancer patients treated with hybrid brachytherapy.</div></div><div><h3>MATERIAL AND METHODS</h3><div>Cervical cancer patients treated with EBRT and MR hybrid brachytherapy were retrospectively analyzed. They were treated without ureter contoured as organ at risk. The right and left ureters were retrospectively contoured on T2 weighted MRI images. Dose to 0.1cc volume of ureter was documented.</div></div><div><h3>RESULTS</h3><div>26 patients treated with hybrid brachytherapy were analyzed. The median HRCTV volume was 23.9cc. The median HRCTV D90 &amp; GTV D98 EQD2 were 91.09Gy (IQR 92.36–87.28) and 104.67Gy (IQR 113.90–95.04) respectively. The median D2cc for bladder, rectum and sigmoid were 75.46Gy, 58.10Gy and 61.3Gy EQD2 respectively. The mean minimum distance of the left ureter from HRCTV was 3.2mm (IQR 6.75–1) &amp; right ureter was 2.3mm (IQR 8–0). The mean D_0.1cc to the left ureter was 75.16Gy EQD2 (IQR 88.28–58.20) and to the right ureter was 69.73Gy EQD2 (IQR 76.77–56.01). The ureter D_0.1cc exceeded 77Gy in 13/26 patients. Replanning and reducing needle loading near the ureter resulted in reduction of ureter 0.1cc dose to less than 77Gy in all but 2 patients, without compromising the HRCTV coverage.</div></div><div><h3>CONCLUSION</h3><div>The ureter is at risk of receiving high doses when we use hybrid applicator. MR planning to delineate the ureter and careful optimization of needles can result in significant reduction of ureter dose with similar target coverage.</div></div>","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":"24 4","pages":"Pages 504-509"},"PeriodicalIF":1.7,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144045015","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The American Brachytherapy Society (ABS) consensus guidance for hybrid intracavitary interstitial brachytherapy for locally advanced cervical cancer","authors":"Junzo Chino ,&nbsp;Beth Erickson ,&nbsp;David Gaffney ,&nbsp;I-Chow Hsu ,&nbsp;Mitchell Kamrava ,&nbsp;Yongbok Kim ,&nbsp;Thomas R. Niedermayr ,&nbsp;Michael Roumeliotis ,&nbsp;Jason Rownd ,&nbsp;Dorin Todor ,&nbsp;Akila Viswanathan ,&nbsp;Elizabeth A Kidd","doi":"10.1016/j.brachy.2025.05.001","DOIUrl":"10.1016/j.brachy.2025.05.001","url":null,"abstract":"<div><h3>PURPOSE</h3><div>The purpose of this consensus statement from the American Brachytherapy Society (ABS) is to summarize important considerations for adding interstitial needles to intracavitary implants for cervix cancer brachytherapy.</div></div><div><h3>METHODS</h3><div>A panel of experts in Gynecologic Brachytherapy, including both physicians and physicists completed surveys and met virtually on multiple occasions to discuss and define current practices and approaches in order to summarize these for the ABS community. This document was drafted, reviewed and approved by the full panel and the ABS Board of Directors.</div></div><div><h3>RESULTS</h3><div>Hybrid brachytherapy is increasingly being utilized in cervix brachytherapy. In incorporating supplementary interstitial needles there are numerous key considerations including resources for an emergency, planning considerations, applicator selection, and pre-, intra- and postprocedural imaging. Additionally, approaches to challenging cases that would often benefit from a hybrid approach are discussed.</div></div><div><h3>CONCLUSIONS</h3><div>While hybrid brachytherapy offers dosimetric advantages for cervix brachytherapy, it increases procedure complexity. Being aware of the necessary resources and defining considerations can help mitigate some of the challenges and improve procedural success.</div></div>","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":"24 4","pages":"Pages 463-478"},"PeriodicalIF":1.7,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144188683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Understanding anxiety in patients receiving vaginal brachytherapy for low-grade early-stage endometrial cancer","authors":"Diane Park ,&nbsp;Sayeh Fattahi ,&nbsp;Yoshie Sawin ,&nbsp;Andrzej Niemierko ,&nbsp;Fantine Giap ,&nbsp;Colleen M. Foote ,&nbsp;Kelly E. Irwin ,&nbsp;Andrea L. Russo","doi":"10.1016/j.brachy.2025.04.001","DOIUrl":"10.1016/j.brachy.2025.04.001","url":null,"abstract":"<div><h3>PURPOSE</h3><div>Vaginal brachytherapy (VBT) is a standard treatment after hysterectomy for early-stage endometrial cancer. Despite only requiring a few treatments with minimal toxicity, many women have significant anxiety regarding VBT. This study was to assess and quantify anxiety in early-stage endometrial cancer patients receiving VBT and to evaluate correlations with clinicopathologic and demographic variables.</div></div><div><h3>METHODS</h3><div>A survey-based cohort study of patients ages 18–99 with stage I-II endometrioid endometrial cancer treated with adjuvant VBT after hysterectomy between 2014 and 2020 was performed to assess experience with VBT and related anxiety. Patients with recurrent disease were excluded. Assessments included: (<em>1</em>) qualitative questionnaire measuring anxiety and mood pre- and post-VBT, (<em>2</em>) clinical factors questionnaire measuring health status, (<em>3</em>) Hospital and Anxiety Depression Scale (HADS), and (<em>4</em>) demographics questionnaire. Pearson’s chi-squared test was used to correlate demographics with anxiety.</div></div><div><h3>RESULTS</h3><div>About 185 patients met inclusion criteria and of those, 75 completed all 4 surveys. Forty-nine patients (65%) reported anxiety or fear prior to receiving VBT, related to concerns of pain (40%), quality of life (27%), bladder/bowel function (24%). On univariate analysis, patients with a college degree or higher, income of ≥ $80,000, and HADS-Anxiety ≥ 8 were significantly more likely to experience anxiety with X² values of 4.64 (<em>p</em> = 0.03), 5.79 (<em>p</em> = 0.02), and 6.49 (<em>p</em> = 0.01), respectively. Only income ≥ $80,000 approached significance on multivariable analysis (<em>p</em> = 0.07).</div></div><div><h3>CONCLUSION</h3><div>A majority of patients experience anxiety prior to treatment with adjuvant VBT. It is important to increase the general knowledge surrounding VBT and to establish educational tools to reduce VBT related anxiety and fear.</div></div>","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":"24 4","pages":"Pages 510-514"},"PeriodicalIF":1.7,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144144925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The use of Monte Carlo simulation techniques in brachytherapy: A comprehensive literature review","authors":"Tirthraj Adhikari ,&nbsp;Tomas Montenegro ,&nbsp;Jae Won Jung ,&nbsp;Courtney Oare ,&nbsp;Gabriel Fonseca ,&nbsp;Luc Beaulieu ,&nbsp;Abdullah Alshreef ,&nbsp;Clara Ferreira","doi":"10.1016/j.brachy.2025.02.006","DOIUrl":"10.1016/j.brachy.2025.02.006","url":null,"abstract":"<div><div>Monte Carlo techniques have become crucial in brachytherapy since their introduction in the early 1980s, offering significant improvements in source parameter characterizations, and dose calculations. It provides precise dose distributions by modeling complex radiation interactions and can be determine doses in nonhomogeneous detailed cases. They are not affected by experimental artifacts, unlike traditional detectors, and can distinguish between primary and scatter dose components. However, MC techniques have limitations. They are susceptible to systematic errors and require thorough validation against experimental data, despite generally showing smaller standard deviations. Additionally, MC simulations can be computationally intensive and depend heavily on accurate input data and models. Recent research, including 1433 publications identified up to October 2024, highlights the ongoing development and application of MC techniques in brachytherapy. Of these, 426 articles met the inclusion criteria for relevance. This comprehensive review aims to help brachytherapy researchers to identify the appropriate MC code depending on the application in BT research. Of the forty-five MC codes used in BT, MCNP is noted as the most widely used MC code due to its robust modeling capabilities in various materials and geometries. AAPM TG-186 and TG-372 reports have recommended the use of model base dose calculation algorithms, since it can offer more accurate dose calculations over TG-43 formalism, particularly in heterogeneous tissues. Despite these recommendations, further research is needed to refine dosimetry for various isotopes, geometry and media. In essence, MC techniques have greatly enhanced the accuracy, precision and flexibility of brachytherapy techniques, though challenges such as systematic errors, heterogeneities corrections, and high computational demands remain. Continued research and development of MC codes and algorithms are essential for advancing the field and improving clinical outcomes.</div></div>","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":"24 4","pages":"Pages 564-621"},"PeriodicalIF":1.7,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143775173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The impact of inherent dose heterogeneity of brachytherapy on calculating iso-effective dose-fractionation regimens for nonmelanoma skin cancers","authors":"Arezoo Karimi ,&nbsp;Nahid Chegeni ,&nbsp;Farshid Mahmoudi ,&nbsp;Seyed Masoud Rezaeijo ,&nbsp;Ali Bagheri","doi":"10.1016/j.brachy.2025.02.001","DOIUrl":"10.1016/j.brachy.2025.02.001","url":null,"abstract":"<div><h3>PURPOSE</h3><div>Utilizing equivalent uniform biologically effective dose (EUBED) concept to calculate iso-effective dose-fractionation regimens in nonmelanoma skin cancer high-dose-rate (HDR) brachytherapy (BT) to address dose heterogeneity and comparing it with the simple form of biologically effective dose (BED) formula.</div></div><div><h3>METHODS AND MATERIALS</h3><div>Two hypothetical HDR BT treatment plans were created for surface and interstitial techniques. Then iso-effective dose-fractionation regimens were calculated (with both EUBED and BED equations) to prescribe a total EQD2₁₀ (equivalent dose in 2 Gy fractions with α/β = 10Gy) of 56, 60 and 65 Gy to the planning target volume (PTV) over a range of five to fifteen fractions. Three different treatment schedules were considered: two and three fraction per week for surface BT and two times a day for interstitial BT. If the treatment duration exceeded 1 month (T_k = 28 days), tumor repopulation was taken into account. Other radiobiological parameters used were α/β = 10Gy, α = 0.3Gy^-1, and T_p = 4 days. Finally, the dose per fraction calculated in the EUBED method was compared with the simple form of the BED formula.</div></div><div><h3>RESULTS</h3><div>The BED formula, compared to the EUBED equation, may lead to less than 5% overestimation in the calculated dose per fraction. This difference is more noticeable in surface BT compared to interstitial implants, especially when prescribing lower total doses, when the total treatment duration in surface BT approaches 28 days, and when using more fractionated interstitial BT treatment regimens.</div></div><div><h3>CONCLUSIONS</h3><div>Based on the findings of this study, dose distribution inhomogeneity in nonmelanoma skin cancer HDR brachytherapy has minimal clinical impact on calculating iso-effective dose-fractionation regimens.</div></div>","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":"24 4","pages":"Pages 543-549"},"PeriodicalIF":1.7,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143782278","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Primary vaginal cancer treated with high-dose rate brachytherapy and intraprocedural magnetic resonance imaging","authors":"Ulysses G. Gardner,&nbsp;Keara English,&nbsp;Michael Roumeliotis,&nbsp;Serena Mao,&nbsp;Todd McNutt,&nbsp;Mohammad Rezaee,&nbsp;Junghoon Lee,&nbsp;Akila N. Viswanathan","doi":"10.1016/j.brachy.2025.03.001","DOIUrl":"10.1016/j.brachy.2025.03.001","url":null,"abstract":"<div><h3>PURPOSE</h3><div>To report outcomes among primary vaginal cancer patients treated definitively with either external beam radiation therapy plus high-dose rate (HDR) brachytherapy (EBRT-BT) or BT (BT) alone with placement of interstitial catheters under magnetic resonance imaging (MRI) guidance.</div></div><div><h3>METHODS</h3><div>Retrospective review of 41 patients treated for primary vaginal cancer from 2016 to 2022. Kaplan-Meier (KM) estimates were generated for disease-free survival (DFS), local control (LC), and overall survival (OS).</div></div><div><h3>RESULTS</h3><div>Median follow-up was 28 months (range 2–82 months). A total of 36 patients had EBRT-BT, 5 had BT alone. Forty patients had template interstitial and 1 had a multichannel cylinder. Among patients who received EBRT-BT, median total D90 EQD2 was 68.3 Gray (Gy) (range 56.6–91.5 Gy)<strong>;</strong> BT only, median 40.3 Gy (range 38.1–86.3 Gy). No patient experienced local only failure. Relapse occurred in 12 patients treated with EBRT-BT versus 1 with BT alone group. For the EBRT-BT cohort versus BT only cohort, 2-year OS was 81% versus 60%, DFS 61% versus 40%, and LC was 94% versus 80%, respectively. For the entire cohort, 2-year OS was 67%, and median OS was 5 years. The 2-year DFS was 57% and 2-year LC was 93%. The most common any grade acute treatment-related toxicity were grade 1 vaginal pain and stenosis. Grade 3 acute and late toxicities were minimal.</div></div><div><h3>CONCLUSIONS</h3><div>MRI-guided HDR BT for primary vaginal cancer yields high rates of local control with limited toxicities. Lower rates of distant control indicate the need for newer options such as immunotherapy or other systemic agents.</div></div>","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":"24 4","pages":"Pages 486-494"},"PeriodicalIF":1.7,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143797268","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The NorCal brachytherapy waste audit: A simple, validated, toolkit for clinician led waste reduction","authors":"Claire C. Baniel ,&nbsp;Katie E. Lichter ,&nbsp;Melissa A. Frick ,&nbsp;Jaclyn Wu ,&nbsp;Eniola Oladipo ,&nbsp;Yufan Fred Wu ,&nbsp;Aneesh SwamyS ,&nbsp;I-Chow Hsu ,&nbsp;Nicolas Prionas ,&nbsp;Erik S Blomain ,&nbsp;Elizabeth A. Kidd ,&nbsp;Mark K Buyyounouski ,&nbsp;Glenn Rosenbluth ,&nbsp;Osama Mohamad ,&nbsp;Hilary P. Bagshaw","doi":"10.1016/j.brachy.2025.01.002","DOIUrl":"10.1016/j.brachy.2025.01.002","url":null,"abstract":"<div><h3>PURPOSE</h3><div>The healthcare system is resource intensive, and many opportunities exist to reduce medical waste. Brachytherapists performing inherently resource intensive procedures are well poised to initiate the transition to sustainable, climate-smart care. The authors developed a quality improvement-based (QI) NorCal Brachytherapy Waste Audit Toolkit to guide medical waste reduction in brachytherapy procedures and provide climate health education.</div></div><div><h3>METHODS AND MATERIALS</h3><div>The NorCal Brachytherapy Waste Audit Toolkit was validated through brachytherapy waste audits conducted at 2 neighboring hospitals between 2021 and 2023. Waste was categorized into biohazardous waste, nonbiohazardous waste, and anesthesia waste and was weighed and cataloged after each procedure using a standard template by auditors not involved in the brachytherapy case. Findings were analyzed for key drivers of waste production and high impact interventions were selected.</div></div><div><h3>RESULTS</h3><div>Postaudit results demonstrate biohazardous waste reduction of greater than 50%, elimination of over 90% improper biohazardous waste sorting, cost savings ($4.22/kg) and a reduction in landfill waste by over 20%. The Toolkit was made public online and over 18 months, was accessed by 34 distinct individuals from 21 healthcare organizations across 7 countries and led to waste reduction projects in multiple specialties including radiation oncology, emergency medicine, and pediatrics.</div></div><div><h3>CONCLUSION</h3><div>A QI-based NorCal Brachytherapy Waste Audit Toolkit may help radiation oncologists and healthcare teams beyond radiation oncology reduce waste and contribute toward environmentally sustainable healthcare.</div></div>","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":"24 4","pages":"Pages 622-630"},"PeriodicalIF":1.7,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143538239","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Choosing between the best, the easiest and the most usual: Three different dose prescription methods for HDR vaginal-cuff brachytherapy planning in postoperative endometrial cancer","authors":"Faegheh Noorian ,&nbsp;Antonio Herreros ,&nbsp;Rosa Abellana ,&nbsp;Clara Baltrons ,&nbsp;Cristian Candela-Juan ,&nbsp;Eduard Agulló-Roca ,&nbsp;Faranak Noorian ,&nbsp;Ángeles Rovirosa","doi":"10.1016/j.brachy.2025.03.005","DOIUrl":"10.1016/j.brachy.2025.03.005","url":null,"abstract":"<div><h3>PURPOSE</h3><div>To evaluate and compare dosimetry parameters of three planning methods in high-dose-rate vaginal cuff brachytherapy (VCB) using cylinders for postoperative endometrial cancer (PEC).</div></div><div><h3>MATERIAL AND METHODS</h3><div>Two hundred seventeen patients were treated with 3D-based VCB for PEC, with the dose prescribed at 5 mm from the applicator surface. Three planning methods were retrospectively compared: T1-arm: point-based optimization at 5 mm from the applicator surface; T2-arm: volume-based optimization; T3-arm: graphical optimization. We evaluated the coverage index (CI), conformity index (COIN), D90 to clinical target volume (CTV) and dose to the organs at risk (OAR).</div></div><div><h3>STATISTICS</h3><div>Descriptive analysis, Chi-square test, Student`s t-test, GEE model, linear regression model.</div></div><div><h3>RESULTS</h3><div>The mean CI was greater than 0.9 in all treatment arms. The T2-arm provided the highest COIN value while T1-arm provided the highest CI value. The T3-arm delivered the lowest doses to the vaginal CTV, rectum and bladder. The linear regression model suggested that in the T3-arm, COIN showed improvement at the expense of CI and achieving a balance between CI and COIN may be more feasible when administering the T2-arm.</div></div><div><h3>CONCLUSION</h3><div>The T2-arm may be considered a general optimization method since it provides a better COIN within an acceptable D90 to the CTV. However, the T3-arm is easier in daily practice and could be more beneficial for patients who are more likely to develop late complications in OAR. More studies are needed to clarify the correlation of late complications with planning methods and dosimetry variables.</div></div>","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":"24 4","pages":"Pages 515-523"},"PeriodicalIF":1.7,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144086908","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"EM tracking with conventional CT tables: Quantifying and correcting for electromagnetic field distortion","authors":"Christopher L. Deufel,&nbsp;Eric E. Brost,&nbsp;Robert Dahl,&nbsp;Jordan McCauley Cutsinger,&nbsp;Bradley J. Stish,&nbsp;Mark R. Waddle,&nbsp;Allison E. Garda,&nbsp;Michael G. Haddock","doi":"10.1016/j.brachy.2025.04.004","DOIUrl":"10.1016/j.brachy.2025.04.004","url":null,"abstract":"<div><h3>PURPOSE</h3><div>To quantify changes in electromagnetic (EM) tracking accuracy due to EM field distortion produced by metal components in conventional computed tomography (CT) tables. Correction methods are presented for restoring accuracy to clinically acceptable levels.</div></div><div><h3>METHODS</h3><div>EM tracking accuracy was evaluated as a function of sensor location and orientation for an NDI Aurora EM tracking system with conventional GE and Siemens CT scanners. Distortion effects were quantified as a function of sensor distance from the EM field generator (EFG) and height above and longitudinal distance along the CT table. A map-based distortion correction method was developed and evaluated using interstitial tandem and ovoid/ring applicator phantoms.</div></div><div><h3>RESULTS</h3><div>Conventional CT tabletops produced EM distortion that resulted in clinically significant localization errors. The error magnitude increased when the sensor was located closer to the CT table surface and further from the EFG. The greatest errors occurred when the sensor position was fixed, but the orientation was varied. Under typical brachytherapy conditions, errors due to sensor translation were &lt;1 mm for translations of ±50 mm, while errors produced by orientation averaged (maximum) 3.5 (5.3) mm for DICOM YZ plane rotations and 2.0 (2.9) mm for DICOM XZ plane rotations. A clinical interstitial tandem and ovoid applicator set had median (min, max) distortion errors of 1.5 (1.3, 4.7) mm for applicator tips and 0.6 (0.0, 4.0) mm for shafts. Map-based distortion corrections reduced these errors to 0.6 (0.2, 1.7) mm and 0.4 (0.0, 1.8) mm.</div></div><div><h3>CONCLUSION</h3><div>The metal components in conventional CT scanner tables produce EM distortion that can result in EM tracking localization errors &gt;5 mm for nonparallel brachytherapy applicator geometries such as the tandem and ovoid or ring. The effects of EM distortion may be reduced by placing the EM field generator closer to the patient or elevating the patient above the table with pads. Distortion corrections can be used to reduce position errors to clinically acceptable levels.</div></div>","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":"24 4","pages":"Pages 550-563"},"PeriodicalIF":1.7,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144251308","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}