Brachytherapy最新文献

{"title":"PL05 Presentation Time: 2:30 PM","authors":"Csaba Polgar MD, PhD, MSc, DSc ,&nbsp;Vratislav Strnad MD, PhD ,&nbsp;Jose Luis Guinot MD ,&nbsp;Cristina Gutierrez Miguelez MD ,&nbsp;Tibor Major PhD, DSc ,&nbsp;Kristina Lössl MD ,&nbsp;Bülent Polat MD ,&nbsp;Peter Niehoff MD, PhD ,&nbsp;Christine Gall PhD ,&nbsp;Wolfgang Uter PhD","doi":"10.1016/j.brachy.2024.08.063","DOIUrl":"10.1016/j.brachy.2024.08.063","url":null,"abstract":"<div><h3>Purpose</h3><div>To report the 10-year late side-effects and cosmetic results of the GEC-ESTRO multicentric phase 3 accelerated partial breast irradiation (APBI) trial.</div></div><div><h3>Materials and Methods</h3><div>Women aged 40 years or older with stage 0-IIA breast cancer who underwent breast-conserving surgery (BCS) with clear resection margins were randomly assigned to receive either whole-breast irradiation (WBI) of 50 Gy with a tumor-bed boost of 10 Gy or APBI with interstitial brachytherapy. The non-inferiority of APBI in terms of local tumor control as primary end-point has been confirmed. Here, we report the secondary endpoints of late side-effects and cosmesis at 7.5 and 10 years of follow-up. This trial is registered with ClinicalTrials.gov number NCT00402519.</div></div><div><h3>Results</h3><div>Between 2004, and 2009, we randomly assigned 1328 women to receive either WBI (n=673) or APBI with interstitial brachytherapy (n=655); 1184 patients comprised the as-treated population and among these 10-year data on late side-effects and cosmetic results were available in 688 patients (313 in the WBI group and 375 in the APBI group). At 7.5 and 10 years 10 (2.7%) and 4 (1.3%) patients in the WBI group and 2 (0.4%) and 1 (0.3%) patients in the APBI group had grade 3 skin teleangiectasia (p=0.02 at 7.5 years and p=0.18 at 10 years). At 7.5 and 10 years 2 (0.5%) and 5 patients (1.6%) in the WBI group and 2 (0.4%) and 3 (0.8%) in the APBI group developed grade 3 late subcutaneous tissue toxicity (p=0.62 at 7.5 years and p=0.53 at 10 years). The incidence of grade 2-3 breast pain at 7.5 and 10 years was 1.6% and 1.0% after WBI versus 1.1% and 0.8% after APBI (p=0.39 at 7.5 years and p=0.93 at 10 years). At 7.5 years brachial lymphoedema occurred more frequently after WBI compared to APBI (5.4% vs 2.2%; p=0.03). At 7.5 and 10 years’ follow-up, according to the patients’ view, 31.9% and 33.8% of patients had excellent cosmetic results in the WBI group versus 44.3% and 45.0% of patients in the APBI group (p=0.001 at 7.5 years and p=0.002 at 10 years); when judged by the physicians, 31.7% and 33.2% of patients in the WBI group versus 40.0% and 40.0% of patients in the APBI group, had excellent cosmetic results, respectively (p=0.05 at 7.5 years and p=0.2 at 10 years).</div></div><div><h3>Conclusions</h3><div>Long-term toxicity profiles and cosmetic results were similar in patients treated with BCS followed by either APBI with interstitial brachytherapy or conventional WBI, with significantly fewer skin teleangiectasia and brachial lymphoedema accompanied with a slightly better cosmetic results after APBI with interstitial brachytherapy. These findings provide further clinical evidence for the routine use of sole interstitial multicatheter brachytherapy after BCS.</div></div>","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":"23 6","pages":"Page S50"},"PeriodicalIF":1.7,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527029","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":"Thursday, July 11, 20244:00 PM - 5:00 PM PP01 Presentation Time: 4:00 PM","authors":"Christopher Jason Tien Ph.D. ,&nbsp;Sean Mullane M.S. ,&nbsp;Emily Draeger Ph.D. ,&nbsp;Mark J. Rivard Ph.D. ,&nbsp;Zhe (Jay) Chen Ph.D.","doi":"10.1016/j.brachy.2024.08.020","DOIUrl":"10.1016/j.brachy.2024.08.020","url":null,"abstract":"&lt;div&gt;&lt;h3&gt;Purpose&lt;/h3&gt;&lt;div&gt;In Ir-192-based high dose rate (HDR) brachytherapy, the dose delivered at the central axis of single-channel vaginal cylinder (SCVC) is inherently lower than the surrounding areas due to the anisotropic dose distribution of the Ir-192 seed. In principle, this situation could be addressed by introducing custom shielding into the dome of SCVC to shape the dose distribution near the central axis. Aided by advanced dose calculation methods, including both Monte Carlo (MC) simulations and Model-Based Dose Calculation Algorithms (MBDCAs), the shape and density of the shielding materials could provide additional degrees of freedom for inverse dose optimization. In this work, we investigate the potential benefits of this approach by investigating the efficacy of an SCVC with custom shielding (SCVC+S) design to flatten the distal dose profile.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Materials and Methods&lt;/h3&gt;&lt;div&gt;A standard SCVC with 140 mm cylinder height (h) and 30 mm outer diameter (OD) with an air channel of 1.6 mm along the central axis for the source transit was used in the initial investigation. The cylinder is capped by a half-spherical dome with a matching diameter (d) of 30 mm. While the existing SCVC is composed entirely of water-equivalent material, the SCVC+S design includes a cavity within the dome which will be injected with stainless steel (mass density of 8.0 g/cc, 6.49 electron density, 13415 HU) shielding material. Three distinct SCVC+S dome designs were explored: A) dome composed of entirely stainless steel except an air channel of d=5 mm along the central axis; B) dome containing one disk “washer” (OD=27 mm, inner diameter (ID)=20 mm, h=1 mm); C) dome containing one disk “washer” (OD=13 mm, ID=3 mm, h=2.5 mm) stacked on a short cylinder (d=13 mm, h=2.5 mm). The SCVC/SCVC+S geometries were independently modeled, with the GammaMed Plus 232 HDR &lt;sup&gt;192&lt;/sup&gt;Ir (dosimetrically identical to Bravos 232A HDR192) radioactive source model for 1) AcurosBV v1.8.0.867816 (Varian Medical Systems, Palo Alto, CA) MBDCA, with dose reported to medium for a 1 × 1 × 1 mm&lt;sup&gt;3&lt;/sup&gt; grid; and 2) Geant4 MC with TOPAS v3.8 toolkit, with tracklength estimator (TLE) dose for 1 × 1 × 1 mm&lt;sup&gt;3&lt;/sup&gt; grid, with n=1 × 10&lt;sup&gt;8&lt;/sup&gt; histories.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Results&lt;/h3&gt;&lt;div&gt;After modeling the 4 (one SCVC and three SCVC+S) applicator designs in EclipseBV and TOPAS, the dose grids were obtained. PORTEC A3 (3.5 mm lateral, 5 mm superior) reference point and lateral dose profiles up to lateral radius (r) of 15 mm were extracted from a plane 5 mm superior to the SCVC tip (normalized to 100% dose at the central axis). The traditional SCVC has region of lowest dose at central axis, with large shoulders, 109% dose at A3, 116% dose at r=10 mm. Design A of SCVC+S has its highest relative dose at central axis, with no shoulders, 92% dose at A3, 61% dose at r=10 mm. Design B of SCVC+S has a wide flat region with shoulders, 100% dose at A3, 104% dose at r=10 ","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":"23 6","pages":"Pages S26-S27"},"PeriodicalIF":1.7,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142525875","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":"PL04 Presentation Time: 2:15 PM","authors":"Gregory Merrick MD ,&nbsp;Martin King MD, PhD ,&nbsp;Kent Wallner MD ,&nbsp;Robert W. Gallbreath PhD ,&nbsp;Ryan Fiano PhD ,&nbsp;Wayne M. Butler PhD ,&nbsp;Peter F. Orio DO, MS","doi":"10.1016/j.brachy.2024.08.062","DOIUrl":"10.1016/j.brachy.2024.08.062","url":null,"abstract":"<div><h3>Purpose</h3><div>To evaluate the necessity and/or dose of supplemental external beam radiotherapy (EBRT) in predicting biochemical failure (BF) and prostate cancer specific mortality (PCSM) in higher-risk prostate cancer patients implanted with Pd-103.</div></div><div><h3>Materials and Methods</h3><div>Eligibility criteria included clinically organ-confined disease with Gleason scores 7-9 and/or a pre-treatment prostate-specific antigen (PSA) of 10-20ng/mL. Trial 44/20 randomized 247 patients to 44Gy + 90Gy Pd-103 vs. 20Gy with 115Gy Pd-103. The subsequent 20/0 trial randomized 383 patients to the 20Gy arm vs. monotherapeutic 125Gy Pd-103. The brachytherapy prescription dose was prescribed to the prostate gland with generous periprostatic margins using extracapsular seeds and implantation of the proximal 10-12mm of the seminal vesicles. Post-implant computerized tomography (CT) based dosimetry was performed on day 0. Biochemical failure (BF) was defined as a PSA &gt; 0.40ng/mL after nadir. Multiple clinical, pathologic and treatment parameters were evaluated for impact on BF, PCSM, and overall mortality(OM).</div></div><div><h3>Results</h3><div>For all 630 patients, the median follow up was 11.8 years with a day 0 D90 of 121.9% of prescription and a V100 of 98.3%. The 13-year BF, PCSM and OM were 5.8%, 1.0%, 30.4%, respectively. For the 44/20 patients (median follow up 13.7 years) BF, PCSM &amp;OM were 8.9%, 2.4% and 39.7% while BF, PCSM &amp; OM for 20/0 (median follow-up 10.4 years) were 3.6%, 0.0% and 21.5%. In part, the difference in outcome between the two groups was due to a significant difference in the number of accrued Gleason score (GS) 8-9 patients (15.8% versus 1.6%). BF and PCSM for FIR, UIR and HR were 3.5% and 0.0%, 7.5% and 1.9%, and 15.2%, and 4.3%, respectively. The median time to BF was 5.1 (range 0.7-10.7), 4.6 (range 0.7-12.3), &amp; 2.9 (range 0.2-7.8) years for FIR, UIR &amp; HR. Neither the addition of EBRT or dose impacted BF (Figure) or PCSM. In multivariate analysis, BF was most closely related to pre-implant PSA (p=0.019, HR=1.154), GS (p=0.008, HR=1.748) &amp; percent positive biopsies (p=0.015, HR=1.020). PCSM was most closely related to pre-implant PSA (p= 0.02, HR=1.218) &amp; GS (p&lt; 0.001, HR=4.178). For all biochemically-controlled patients, the median PSA was&lt; 0.02 ng/ml.</div></div><div><h3>Conclusions</h3><div>In this study, consistent, high-quality Pd-103 dose distributions with aggressive extra-capsular and proximal seminal vesicle coverage resulted in durable biochemical control rates in patients with higher-risk features. The addition of supplemental EBRT did not impact BF or PCSM.</div></div>","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":"23 6","pages":"Pages S49-S50"},"PeriodicalIF":1.7,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142526753","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":"PHSOR03 Presentation Time: 9:10 AM","authors":"Birjoo Vaishnav PhD, DABR","doi":"10.1016/j.brachy.2024.08.077","DOIUrl":"10.1016/j.brachy.2024.08.077","url":null,"abstract":"&lt;div&gt;&lt;h3&gt;Purpose&lt;/h3&gt;&lt;div&gt;Clinical experience or nomograms guide day to day clinical decisions for HDR prostate brachytherapy such as whether there ought to be one more catheter to ensure coverage or whether a given catheter would be unusable as it is too close to urethra. AI or machine learning offers the possibility to mimic this with backing from clinical data. The purpose of this study utilizing simulated data was to explore feasibility of using AI/Machine Learning in answering routine questions during the HDR prostate planning process, such as the number of catheters needed to ensure optimal coverage while ensuring urethral sparing.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Materials and Methods&lt;/h3&gt;&lt;div&gt;Data from the catheter insertion and planning during HDR prostate cases such as volume of prostate in the ultrasound and CT, number of catheters are available during insertion and after digitization and optimization the D10% for the Urethra, V150 and V200 for the prostate for a V100 ∼ 95% is obtained. To separate the characteristics of the AI modeling from the peculiarities of the clinical data, a simulated dataset with a gaussian distribution with similar bounds as the typical clinical data was created. AutoML is a subset of machine learning which automates the model validation and evaluation. Using various preset criteria, models are trained on data using fivefold cross validation and a portion of data is held for future testing as a holdout. The scoring metric from this is then used for automatically evaluating the performance of models and choosing the optimal model. Various software solutions were explored for deploying AutoML with low or no code and ability to evaluate the underlying machine learning model predictions being the criterion. The user interface for two of the vendors datarobot and symon.ai were intuitive and easily deployable in comparison to the bigger vendors in the field, of the two, free trial online version of datarobot was used for this study. AutoML was trained and deployed on a set of 51 rows with four of the predictive features - TRUS volume of prostate, number of slices, CT volume and the Dose to 10% of the urethra were used as the training data set for machine learning, with the number of catheters as the target. After completion of the run, the output of top five of the algorithms (elastic net, extreme gradient boosted trees, ridge regressor, light gradient and random forest) were calculated just to evaluate how far off they were from each other and ground truth, using another set of 48 rows of data with some overlap with the training data.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Results&lt;/h3&gt;&lt;div&gt;While it was easy to deploy and create a model with this platform, several other platforms such from leaders in the field were much harder to set up and troubleshoot. The outputs for the test data were evaluated relative to the ground truth and the elastic net had the least deviation from the ground truth both in terms of the overall data spread and the deviat","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":"23 6","pages":"Pages S58-S59"},"PeriodicalIF":1.7,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142526754","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":"MSOR8 Presentation Time: 5:35 PM","authors":"Kiriti Chiriki DNB,&nbsp;Umesh Mahantshetty MD, DNB, DMRT,&nbsp;Rohit Vadgoankar MD,&nbsp;Pankaj Chauhan MDS, PhD,&nbsp;Sasi Krishna Kavutarapu Mch,&nbsp;Rao N Nageswara Mch,&nbsp;KK Sree Lakshmi MSC, DRP,&nbsp;Raghavendra Hajare MSc, DRP,&nbsp;Sneha Nachu BDS,&nbsp;Raviteja Miriyala MD","doi":"10.1016/j.brachy.2024.08.042","DOIUrl":"10.1016/j.brachy.2024.08.042","url":null,"abstract":"&lt;div&gt;&lt;h3&gt;Purpose&lt;/h3&gt;&lt;div&gt;To elucidate systematic approach towards commissioning, implementing and establishing a high dose rate (HDR) interstitial brachytherapy (ISBT) program for head and neck cancers in a new tertiary cancer centre in India.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Materials and Methods&lt;/h3&gt;&lt;div&gt;We present the systematic approach and challenges encountered during the implementation of ISBT for head and neck cancers and early outcome of patients treated between September 2020 and September 2022 at our Institution.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Results&lt;/h3&gt;&lt;div&gt;In an established infrastructure for high Dose rate Brachytherapy, we explored implementing H &amp; N BT. Joint tumor board discussions, reviewing of existing treatment guidelines and shared decision making with patients helped to start the program. A comprehensive disease mapping was done using clinical drawings (figure 1) &amp; clinical pictures taken before EBRT and BT. Appropriate check list for performing BT procedure, discussions for anaesthesia requirements, dedicated team of Nurse, RTT &amp; Medical physicist, BT planning and dose parameters were reviewed. A successful collaboration with dental surgeon to work on prosthesis especially to spare mandible for high dose regions was established which evolved from using simple rubber catheters, wax to customized acrylic spacers. All suitable patients were either offered radical BT or BT boost after completion of EBRT.A total of 18 patients diagnosed with early-stage oral cancer underwent treatment with ISBT, either as a boost following VMAT (n=13) or 3DCRT (n=2), or as BT Alone (n=3). The primary tumour sites were lateral border of the tongue (n=13), lip (n=3), and buccal mucosa (n=2). The median tumour size was 2 cm, with 13 cases classified as T1 and 5 as T2 with infiltrative lesion in 13 pts and proliferative lesion in remaining 5 pts.Three patients received ISBT alone (1 with buccal mucosa cancer, 2 with lip cancer), while 15 underwent concurrent neck irradiation alongside primary tumour treatment, with a median dose of 50 Gy in 25 fractions over 5 weeks, followed by HDR ISBT after a median gap of 31 days (IQR, 18-34 days). Most patients (n=9,50%) required implantation in two planes, with a median of 11 catheters (range 9-15). The median dose for ISBT boost cases was 22.5Gy in 5 fractions @ 4.5Gy/fraction, while for radical ISBT, it ranged from 40 Gy in 10 fr to 49.5 Gy in 11 fr. The EQD2 was 74 Gy (range: 69-77.5 Gy EQD2), and the median overall treatment time for combined EBRT and ISBT boost was 67 days (range: 47 - 88 days). Mandibular ISBT doses were limited to a median of 4.3 Gy (D 0.1 cc) and 3.15 Gy (D 1cc) per fraction with cumulative dose(Dmax) in EQD2 of 53Gy. The prescribed dose for radical ISBT ranged from 40 to 48 Gy in 10-15 fr.At the last follow-up, grade 1 xerostomia was reported in 38.9% of patients, with none experiencing grade 2 or higher xerostomia. One patient developed osteoradionecrosis of the mandible with minimal exposure","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":"23 6","pages":"Page S39"},"PeriodicalIF":1.7,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142526755","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":"MSOR5 Presentation Time: 5:20 PM","authors":"Christopher P. Cifarelli MD, PhD, MMM ,&nbsp;Kevin Petrecca MD ,&nbsp;Henning Kahl MD ,&nbsp;Oliver Ganslandt MD, PhD ,&nbsp;Tamer Abdelrhman MD, PhD ,&nbsp;Stephanie Combs MD ,&nbsp;Gustavo Sarria MD ,&nbsp;Frank A. Giordano MD","doi":"10.1016/j.brachy.2024.08.039","DOIUrl":"10.1016/j.brachy.2024.08.039","url":null,"abstract":"<div><h3>Purpose</h3><div>While the use of 5-ALA has been used to increase the extent of surgical resection in glioblastoma (GBM), its potential to act as a radiosensitizer has not been widely studied in the CNS. Whereas typical external beam radiotherapy (EBRT) treatments occur weeks after surgery and 5-ALA administration, intraoperative radiotherapy (IORT) delivers radiation while protoporphyrin IX is still present in residual tumor. This current study examines the potential for radiation necrosis (RN) development following IORT and subsequent fractionated radiotherapy.</div></div><div><h3>Methods</h3><div>Interim data from the INTRAGO II study for newly diagnosed GBM (NCT02685605) were analyzed for the incidence of radiation necrosis (RN) based on 5-ALA use, IORT treatment vs SOC control (60Gy EBRT), and extent of resection. Statistical analysis was performed via univariate (ANOVA), multivariate (Cox regression), and K-M estimations with significance of p&lt;0.05.</div></div><div><h3>Results</h3><div>234 patients were enrolled in INTRAGO II between 2016 and 2022. Of these, 185 (79%) had a surgical resection performed with the use of 5-ALA tumor fluorescence visualization. Following surgical resection with 5-ALA, 94 (51%) received IORT (30Gy to the margin) and an additional 60Gy EBRT (ARM A). Imaging confirmed RN occurred in 11 (12%) of ARM A patients who had 5-ALA assisted resection, compared to 3 (3.3%) of ARM B patients who received only 60Gy EBRT. In the 49 patients not receiving 5-ALA, the imaging confirmed the RN rate in ARM A patients was 21% (5/24) compared to 12% in ARM B (3/25). The median time to development of RN was 236 days post-IORT and 158 days post completion of EBRT. ANOVA demonstrated a significantly (p=0.025) higher rate of RN in ARM A patients overall, but not with the addition of 5-ALA. Cox regression analysis confirmed that only significant predictor of RN on multivariate analysis was IORT plus EBRT (p=0.033) and KM estimations-Log Rank test of RN incidence were greater in Arm A/IORT patients than SOC/Arm B (p=0.029).</div></div><div><h3>Conclusions</h3><div>While patients receiving IORT at the time of surgical resection had a higher rate of RN after SOC 60Gy EBRT, the use of 5-ALA in conjunction with surgical resection did not increase RN incidence. Further analysis will need to consider local PFS rates and the impact of 5-ALA use with IORT.</div></div>","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":"23 6","pages":"Pages S37-S38"},"PeriodicalIF":1.7,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142526610","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":"GSOR02 Presentation Time: 5:05 PM","authors":"Jasmine Zhang BA ,&nbsp;Erin Herbert BS ,&nbsp;Teresa M. Meier MD ,&nbsp;Thomas L. Minges DNP, CRNA ,&nbsp;Jordan Kharofa MD ,&nbsp;Sarah M.C. Sittenfeld MD","doi":"10.1016/j.brachy.2024.08.048","DOIUrl":"10.1016/j.brachy.2024.08.048","url":null,"abstract":"&lt;div&gt;&lt;h3&gt;Purpose&lt;/h3&gt;&lt;div&gt;In 2015, we transitioned from performing gynecologic brachytherapy procedures in an operating room in the hospital under general anesthesia, to a departmental procedure room with preference for spinal anesthesia. MRI was in the main hospital and generally obtained with fraction 1 and fused to CT scans for subsequent fractions. We sought to review the feasibility and tolerability of this workflow utilizing spinal anesthesia and extra-departmental MRI.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Materials and Methods&lt;/h3&gt;&lt;div&gt;This was an IRB-approved, retrospective review of gynecologic brachytherapy procedures performed in a departmental procedure room at a single center from 4/2015-3/2023. Demographic information and treatment-related data including procedure details, imaging used for treatment planning, type of anesthesia, total time in the department, and highest pain score were obtained. OR procedures that required admission with implant in place were excluded from analysis.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Results&lt;/h3&gt;&lt;div&gt;A total of 141 patients undergoing 541 procedures were included. The most common diagnosis was cervical cancer (n = 118) followed by endometrial and vaginal cancer. Most patients (98%) underwent external beam radiation therapy ± chemotherapy prior to brachytherapy. The most common brachytherapy regimen was 28 Gy in 4 fractions, delivered twice weekly, and the average overall treatment time was 52.6 days. Tandem and ring was the most frequently used applicator (n = 89), and 38 patients had hybrid or interstitial implants. Eighty-two percent of patients received spinal anesthesia. For those undergoing general anesthesia, the most common reasons were low platelets (52%) or anticoagulation (32%). There were no complications from spinal anesthesia in this cohort. Sixty-seven percent of patients underwent MRI with applicator in place and 22% had pre-brachytherapy MRI. For fractions performed when only a CT scan was obtained for planning, average total time in the department was 346 minutes (min). Patients who received spinal anesthesia spent a longer time in the department than patients who received general anesthesia (average of 353 min vs. 325 min, p=0.00005). Similar trend was seen on fractions when an MRI was obtained, with average time in the department of 371 min for those under spinal anesthesia vs. 346 min for those under general anesthesia (p=0.04). When comparing fractions when an MRI was obtained vs. CT scan only, the MRI added an average of 20 min to the total time (366 min vs. 346 min). Patients receiving spinal anesthesia had a lower average pain score than those receiving general anesthesia (1.63 vs. 2.34, p=0.02). Overall, only 17% of patients required narcotics for post-procedure pain control regardless of type of anesthesia received, and the majority of these (91%) required only 5-10 mg of oxycodone or equivalent for adequate pain control.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Conclusion&lt;/h3&gt;&lt;div&gt;Spinal anesthesia is feasible and offers goo","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":"23 6","pages":"Page S42"},"PeriodicalIF":1.7,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142526542","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":"BP03 Presentation Time: 4:18 PM","authors":"Sylwia Kellas-Sleczka PhD ,&nbsp;Stankiewicz Magdalena PhD ,&nbsp;Wojcieszek Piotr PhD ,&nbsp;Szlag Marta PhD ,&nbsp;Lelek Piotr MD ,&nbsp;Sleczka Maciej PhD ,&nbsp;Cholewka Agnieszka MS","doi":"10.1016/j.brachy.2024.08.027","DOIUrl":"10.1016/j.brachy.2024.08.027","url":null,"abstract":"<div><h3>Purpose</h3><div>The study aims to present the long-term results of 508 cases of early breast cancer treated with accelerated partial breast irradiation (APBI) using interstitial multicatheter high-dose-rate brachytherapy (HDR-BT) following breast-conserving surgery (BCS) in a single institution.</div></div><div><h3>Materials and Methods</h3><div>Between July 2006 and December 2020, a total of 514 cases of low-risk invasive and in situ carcinoma after BCS were treated with APBI using interstitial multicatheter HDR brachytherapy (MIB) at our department and 508 who met the inclusion criteria were analyzed. The inclusion criteria were: ZUBROD 0 or 1, age ≥50 years, pT1-2aN0 cM0, tumor size ≤3 cm, unifocal, invasive carcinoma without neuroinvasion or angioinvasion, with a minimal surgical margin of 2 mm or DCIS with a minimal margin of 5 mm, without extensive intraductal components, positive estrogen receptors. A total dose of 32 Gy in 8 fractions was delivered twice daily with a minimum 6-hour interval. The recommended dose constraints from the Groupe Européen de Curiethérapie and the European Society for Radiotherapy and Oncology (GEC ESTRO) were followed. The primary endpoint was local recurrence.</div></div><div><h3>Results</h3><div>The median age was 65 years (range 46-86 years). The median follow-up was 101 months (range 5-209 months). No serious complications occurred during the procedure and all patients completed the treatment without interruptions. The treatment was well tolerated. In the first 40 cases the 2D treatment planning was used, while in the subsequent cases - 3D treatment planning. The recommended dose-volume limits for the implant, planning target volume (PTV) and organs at risk (OARs) were met. The mean volume of the PTV was 74 cc, with the average coverage with the prescribed dose (PTV ref) of 94%. The mean conformity index (COIN) was 0.69, while the mean dose homogeneity index (DHI) was 0.67. There were no grade ≥ 3 complications. In the whole group, a total of 10 local recurrences (1.96%) were observed. In 3 cases distant metastases (0.6%) and ipsilateral breast tumor recurrence in 8 cases (1.57%) were observed. The 5- and 10-year overall survival (OS) was 97.5% and 96.6%, respectively. The 5- and 10-year disease-free survival (DFS) was 95.6% and 91.3%, respectively.</div></div><div><h3>Conclusions</h3><div>APBI with interstitial multicatheterhigh-dose-rate brachytherapy is a safe and effective treatment, associated with a good toxicity profile and low relapse rates. We believe that patient selection criteria should be revised and possibly expanded. However, further studies are required to validate this approach.</div></div>","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":"23 6","pages":"Page S31"},"PeriodicalIF":1.7,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527271","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":"BP05 Presentation Time: 4:36 PM","authors":"Dylan Richeson MS,&nbsp;Robert Hawranko MS,&nbsp;Dorin Todor PhD","doi":"10.1016/j.brachy.2024.08.029","DOIUrl":"10.1016/j.brachy.2024.08.029","url":null,"abstract":"&lt;div&gt;&lt;h3&gt;Purpose&lt;/h3&gt;&lt;div&gt;High dose-rate brachytherapy can be plagued by a multitude of user errors that could result in late toxicities for patients. A common one reported to NRC is wrong treatment length. This error will result in a shifted dose distribution between planned and delivered dose. To automate and verify delivery with correct treatment lengths, Varian released its Bravos remote afterloader which uses the device's dummy wire for accurate pre-treatment applicator measurements. Bravos measurements are compared with the planned lengths and if differences are small, treatment length is adjusted automatically. In this process, dwell positions are kept unchanged relative to the tip of the applicator. In breast interstitial implants, from our clinical experience, we noticed, through these automated measurements a significant catheter lengthening that occurs between the first and second fractions. The first fraction is typically delivered within 2h from implantation and the second fraction is more than 12h later. The catheters length does not seem to change much after that. We seek to quantify the dosimetric impact of such automated adjustments, identify cases and treatment parameters particularly sensitive to these effects and describe the best planning and delivery mitigation strategies to ensure accurate dose delivery.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Materials and Methods&lt;/h3&gt;&lt;div&gt;A retrospective cohort of 14 successively treated breast cancer patients using multi-catheter implants were selected for analysis. Actual length measurements were used to create plans simulating the dosimetric impact of making or not making these adjustments. Daily QA for two years shows positional accuracy of 0.3±0.3mm and for the dummy and source wires. In these simulations, it was hypothesized that the target did not change in volume or position relative to breast. In planning these treatments, two targets are used, expansions of the lumpectomy cavity, a CTV1cm and CTV1.5cm for which we try to achieve V95&gt;95% and V90&gt;90% respectively. The max skin dose is limited to &lt;100% Prescription dose regimens included 7.5Gyx3fx=22.5Gy(8/14 patients) and 4.3Gyx7fx=30.1Gy(6/14 patients). Dose inhomogeneity was evaluated using V150% and V200% for breast tissue. The skin contour encompassed an area 5mm from the surface of the breast and the maximum dose was evaluated using D0. 1cc.The change in catheter lengths, as measured by Bravos, were recorded for each fraction of a patient's treatment.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Results&lt;/h3&gt;&lt;div&gt;The following results show single fraction changes between the original clinically delivered plan and the re-plan which does not consider catheter lengthening by the amount measured by Bravos prior to the second fraction) averaged over all 14 cases. The average reductions in the V95% of the cavity 1.0 and V90% of the cavity 1.5 structures were -0.49±0.99% and -2.93±2.85%, respectively. Negligible changes in normal tissue dose were observed with an avera","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":"23 6","pages":"Page S32"},"PeriodicalIF":1.7,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527273","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":"PP03 Presentation Time: 4:18 PM","authors":"Samantha Simiele PhD ,&nbsp;Manik Aima PhD ,&nbsp;Frank-Andre Siebert PhD ,&nbsp;Joel Poder PhD ,&nbsp;Luc Beaulieu PhD ,&nbsp;Christopher Melhus PhD ,&nbsp;Susan Richardson PhD","doi":"10.1016/j.brachy.2024.08.022","DOIUrl":"10.1016/j.brachy.2024.08.022","url":null,"abstract":"&lt;div&gt;&lt;h3&gt;Purpose&lt;/h3&gt;&lt;div&gt;The documented decline in brachytherapy (BT) utilization in some parts of the world has caused concern for the impact this may have on resident (or equivalent) training and education. The AAPM established a BT survey subunit (UN72) in 2018 with the goals of (1) assessing the current state of medical physics resident BT education on a global scale and (2) collecting data to allow comparison of BT training challenges and opportunities between different organizational systems.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Materials and Methods&lt;/h3&gt;&lt;div&gt;UN72 collaborated with representatives from COMP, GEC-ESTRO, and ABG. The team designed a survey consisting of 26 questions of four types, including multiple choice, select all that apply, free response, and five-point scale. Information was collected in six subject areas including: (1) Trainee demographics, (2) Training methods, (3) Caseload and confidence levels, (4) Future plans and interest in performing BT, (5) Interest in additional BT training opportunities, and (6) Trainee practice impressions. The survey was reviewed and approved for distribution by the AAPM as well as the UN72 collaborators. Within the AAPM, the survey was distributed to current residents and recent graduates of CAMPEP-accredited medical physics residency programs. This survey closed in March 2022 and the results are summarized in a manuscript currently under review. The same survey was distributed separately to resident members of COMP, GEC-ESTRO, and ABG and was closed for responses in March 2022. This abstract summarizes the results of the international survey, considering the contributions of GEC-ESTRO, ABG, and COMP.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Results&lt;/h3&gt;&lt;div&gt;The survey received 183 (AAPM), 41 (ABG), 106 (GEC-ESTRO), and 13 (COMP) responses. The majority of respondents from AAPM (60%), ABG (67%), and GEC-ESTRO (69%) had completed their training whereas 62% of COMP respondents were currently enrolled in their program at the time of survey completion. The results presented are for those who had completed their training program. At least 63% of respondents in each organization expressed interest in performing BT at their first post-residency position and at least 55% in each organization indicated their first position would require them to perform BT. 64% (AAPM), 56% (GEC-ESTRO), 59% (ABG) and 40% (COMP) of respondents wished they had additional BT training opportunities. Of those expressing interest in additional training opportunities, the majority in each organization said they would be ‘very likely’ or ‘likely’ to select BT as an elective rotation if one were offered at their training institute, the majority expressed interest in performing a post-residency fellowship (Figure 1) if one were available, and 76% (AAPM), 83% (GEC-ESTRO), 84% (ABG), and 50% (COMP) expressed interest in completing a BT rotation at an institution with a higher caseload or a greater variety of cases.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Conclusions&lt;/h3&gt;&lt;div&gt;The majo","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":"23 6","pages":"Page S28"},"PeriodicalIF":1.7,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527067","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}