Brachytherapy最新文献

{"title":"GPP06 Presentation Time: 9:45 AM","authors":"Raviteja Miriyala M.D , KK Sreelakshmi M.Sc.,D.R.P , Kiriti Chiriki D.N.B , Raghavendra Hajare M.Sc., D.R.P , Rohit Vadgaonkar M.D , Sneha Nachu B.D.S , Surbhi Grover M.D , Umesh Mahantshetty M.D, D.N.B","doi":"10.1016/j.brachy.2024.08.008","DOIUrl":"10.1016/j.brachy.2024.08.008","url":null,"abstract":"<div><h3>Purpose</h3><div>Consensus recommendations for CT based contouring in Image Guided Adaptive Brachytherapy (CT-IGABT) for cervical cancer were published by IBS-GEC ESTRO-ABS. However, real world outcome data of patients treated based on these recommendations is sparse. The purpose of this study is to present early outcomes of cervical cancer patients treated with CT-IGABT using the IBS-GEC ESTRO-ABS recommendations.</div></div><div><h3>Material and Methods</h3><div>Retro-LACER is a mono-institutional database of cervical cancer patients treated with CT-IGABT using uniform target delineation protocols between August 2020 and July 2023. All consecutive patients with biopsy proven locally advanced cervical cancer (FIGO Stage IB3 to IVA) who received curative (chemo) radiation at our institution were screened. While the dosimetric details were maintained prospectively, outcome and treatment related morbidity data is collected retrospectively from the electronic medical records.</div></div><div><h3>Results</h3><div>Out of 318 patients screened, 73 were excluded as per the eligibility criteria (2, stage ≤ IB2; 3 stage IVB; 19, received EBRT elsewhere; 17 defaulted / received BT elsewhere; 21, participants in other interventional studies; 11, did not come for at least one post treatment follow up). Disease and treatment characteristics of the 245 patients included in this analysis are presented in Table 1. Hybrid IC+IS BT was used in 51.4% of patients. About 64.5% of patients were treated in a basic CT environment (CT alone at BT), while 35.5% were treated in an advanced CT environment (pre-BT MRI, in 3.6% and Trans-Rectal ultrasonography in 31.8%). Median volume of CTV_HR was 31cc, while median D90 and D98 to CTV_HR (in EQD2<sub>10Gy</sub>) were 88 and 79, respectively. Median D2cc for bladder, rectum and sigmoid (in EQD2<sub>3Gy</sub>) were 89, 68 and 67, respectively. Dosimetric details of patients treated in basic and advanced CT environments are also presented in Table 1. At a median follow up of 17 months (IQR, 9 to 26), 12 patients (4.9%) died due to disease and 3 (1.2%) were lost to follow up. Treatment failure was observed in 27 patients (11%), with isolated local, regional (pelvic), regional (para-aortic), regional (pelvic + para-aortic) and distant failures in 3 (1.2%), 0 (0%), 5 (2%), 1 (0.4 %) and 12 (5.2%) respectively. Combination of [local + regional], [regional + distant] and [local + regional + distant] failures was observed in 2 (0.8%), 3 (1.2%) and 1 (0.4%) respectively. Estimated survival probability (Kaplan-Meier) at 6 months and 1 year were 99.5% and 93% for local control, 99.1% and 92% for loco-regional relapse free survival and 100% and 95% for overall survival, respectively. Severe late GI and GU morbidity (CTCAEv5 ≥ Grade 3) was observed in 18 (7.3%) and 1 (0.4%), respectively. Among the patients who developed severe late GU and GI morbidity, median D2cc doses to bladder, rectum and sigmoid (in EQD2<sub>3Gy</sub>) were","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":"23 6","pages":"Page S19"},"PeriodicalIF":1.7,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142526544","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":"PHSOR11 Presentation Time: 9:50 AM","authors":"Juanjuan Fu MS,&nbsp;Zhaobin Li MS,&nbsp;Zhen Li MS,&nbsp;Jie Fu MD","doi":"10.1016/j.brachy.2024.08.085","DOIUrl":"10.1016/j.brachy.2024.08.085","url":null,"abstract":"<div><h3>Purpose</h3><div>This study focuses on determining the optimal MRI scanning parameters for precise localization of MR-line markers, and to investigate their apical reconstruction error.</div></div><div><h3>Materials and Methods</h3><div>In the study, it was assumed that the front seal of each MR-line marker was identical. Three MR-line markers were individually placed at the tips inside the tubes of plastic sharp needles. The position of the plastic-tipped sharp needles was marked with three additional MR-line markers. These needles, along with the markers, were then fixed into the same L-shaped (rectangular) mold to ensure that the plastic sharp needles and their corresponding MR-line markers maintained a stable, horizontal alignment and were immobilized during the process. The physical distance measured between the tips of the two MR line markers, one located inside and the other outside the plastic sharp needle, was approximately 2.30mm. To evaluate the apical reconstruction error of the MR-line marker,10 sets of MR images were acquired with varying slice thicknesses, including T1-weighted images with thicknesses of 3 mm, 2 mm, and 1.4 mm, and T2 -weighted images with thicknesses of 3 mm, 2 mm, and 1 mm.</div></div><div><h3>Results</h3><div>The analysis of the image distance between the MR-line marker tips, both inside and outside plastic sharp needle, revealed that the probability of the measurement of the MR-line marker being within 1 mm accuracy was 92.59%. It was observed that the thickness of the MR images positively correlated with both the mean and standard deviation of the image measurement value in T1-weighted scans. Additionally, the standard deviation of MR-line marker image measurements in T2-weighted scans showed a slight increase as the layer thickness was reduced to 2mm. Upon comparing the results from the three sets of MR-line marker image measurements, it was found that the overall results of T2-weighted scans at 3 mm and T1-weighted scans at 1.4 mm were similar. However, it is important to note that the thinner slice parameter not only restricts the length of the scan, but also leads to increased scanning time and additional time required for contouring before brachytherapy treatment, resulting in increased discomfort for the patient. Therefore, a scanning parameter of T2-weighted scans at 3 mm is recommended for the reconstruction of the MR-line marker.</div></div><div><h3>Conclusions</h3><div>The study demonstrated that the MR-line marker possesses significant potential for clinical application, particularly in the precise localization of plastic sharp needles. This finding is pivotal as it provides a crucial experimental foundation for the implementation of an MR-only workflow in interstitial gynecologic brachytherapy.</div></div>","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":"23 6","pages":"Pages S63-S64"},"PeriodicalIF":1.7,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527289","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, 20245:00 PM - 6:00 PM GSOR01 Presentation Time: 5:00 PM","authors":"Dulce M. Barrios MD ,&nbsp;Mitchell Kamrava MD ,&nbsp;Jenna M. Kahn MD ,&nbsp;Vonetta M. Williams MD ,&nbsp;Keyur J. Mehta MD ,&nbsp;Aaron Wolfson MD ,&nbsp;Lorraine Portelance MD ,&nbsp;Amanda Rivera MD","doi":"10.1016/j.brachy.2024.08.047","DOIUrl":"10.1016/j.brachy.2024.08.047","url":null,"abstract":"&lt;div&gt;&lt;h3&gt;Purpose&lt;/h3&gt;&lt;div&gt;To determine the current practice patterns of analgesia (AG) and anesthesia (AS) use across the U.S. for gynecologic brachytherapy (BT) procedures.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Methods and Materials&lt;/h3&gt;&lt;div&gt;A 27-item survey was created with expertise from five practicing radiation oncology brachytherapists in the U.S. and distributed electronically to 90 Radiation Oncology residency programs for dissemination. The survey was also publicized on social media via the X (formally Twitter) platform, and at two national meetings (The American Brachytherapy Society Annual Meeting 2023 and The American Society for Radiation Therapy Annual Meeting 2023) during the months of June-October 2023.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Results&lt;/h3&gt;&lt;div&gt;Forty-one responses were received (46% response rate). Fifty-four percent identified as female, 66% Caucasian race and 85% of non-Hispanic/Latino ethnicity. Ninety-three percent were physician brachytherapists, 5% medical physicists, and 2% did not disclose their profession. Forty nine percent reported typically carrying out procedures in a BT suite ± separate CT simulator alone, 39% in the operating room ± BT suite or CT simulator or other location. Ten percent reported the CT simulation room alone, and 2% in a clinic exam room. The number of cervix BT courses most frequently performed per month was between 0 and 5 at 61%, and 44% reported an average of five applicator placements per course (range 0-5). Thirty four percent reported using general anesthesia alone (GA) for intracavitary BT (n=41), 20% conscious sedation (CS) alone, 10% oral analgesia (OA) alone, and 9% spinal or epidural AS alone. The remaining responses were combinations of AG or AS (see table 1). Hybrid intracavitary/interstitial BT applicators are being used by 61% of respondents, 49% of which are vendor made devices (e.g., Elekta/Varian). Among those performing hybrid BT (n=25), 40% use GA alone, 16% use CS alone, 12% epidural or spinal AS alone, and 4% OA alone. The remaining responses were combinations of AG or AS. For template interstitial BT (n=25), 44% use GA alone, 48% epidural alone or in combination with other AS, and 8% CS alone. Twenty-two percent of all respondents report providing AG or AS during applicator placement only, while 32% report offering it during placement, planning, treatment, and removal. The most commonly cited reason for not using CS or GA was lack of anesthesia resources and clinician preference. Seventy-three percent reported the belief that patients suffer from post-traumatic stress disorder (PTSD) symptoms after BT. However, 68% reported not using techniques to help alleviate emotional distress related to BT procedures.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Conclusions&lt;/h3&gt;&lt;div&gt;AG/AS practice patterns for gynecologic BT vary widely across the United States. While many clinicians report using some form of GA, CS or epidural AS, 10% are using only oral analgesia methods, and 22% are offering AG/AS only during applicator placement. ","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":"23 6","pages":"Pages S41-S42"},"PeriodicalIF":1.7,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142526541","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":"PHSOR06 Presentation Time: 9:25 AM","authors":"Sharbacha Edward PhD in Medical Physics,&nbsp;Justin Mikell PhD,&nbsp;Jose Garcia-Ramirez MS,&nbsp;Michael B. Altman PhD,&nbsp;Phillip D. Wall PhD,&nbsp;Anamaria Guta MS,&nbsp;Jason LaBrash BS,&nbsp;Jessika A. Contreras MD,&nbsp;Jacqueline E. Zoberi PhD","doi":"10.1016/j.brachy.2024.08.080","DOIUrl":"10.1016/j.brachy.2024.08.080","url":null,"abstract":"&lt;div&gt;&lt;h3&gt;Purpose&lt;/h3&gt;&lt;div&gt;Two high dose rate (HDR) remote afterloaders (RALs) were recently accepted and commissioned for use in our clinic. These RALs are unique in that prior to treatment, they measure each connected applicator + transfer guide tube (TGT) channel length with the dummy wire. If this measurement deviation is within some user-specified tolerance, the RAL automatically adjusts the planned channel length (and subsequent dwell positions) used for treatment by the active wire. This work evaluates the positional accuracy of these units and reports their performance over the first few months of gynecologic patient treatments.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Materials and Methods&lt;/h3&gt;&lt;div&gt;Acceptance testing and commissioning were performed for both units: RAL1 in August 2023, and RAL2 in November 2023. Applicator + TGT channel length verification tests were performed as part of this process. Channel lengths were measured with two independent ruler systems provided by the manufacturer. Manually measured channel lengths were within 0.5 mm of the baseline nominal values provided by the manufacturer. In order to quantify RAL positional accuracy, rigid fixed length applicators - including tandems, ovoids, cylinders, and Simon-Heyman capsules - were affixed to radiochromic film, and double exposure irradiations were performed. First, they were irradiated using a mobile C-Arm fluoroscopy unit. An autoradiograph was then acquired using mock treatment plans designed using nominal channel lengths as the planned lengths, and delivered by the RALs using an ideal applicator setup, i.e. minimizing curvature of TGTs. We configured the RAL to automatically adjust dwell positions when the difference between the RAL-measured and planned channel lengths were within 2 mm. Dwell position deviations measured on film were compared with differences between planned and RAL-measured channel lengths. The record and verify system's treatment summary was queried to extract the RALs’ measured channel lengths. The performance of each RAL was assessed over time by comparing the treatment summary channel lengths for patient treatments with the planned values.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Results&lt;/h3&gt;&lt;div&gt;Double exposure films indicated that, on average, dwell positions deviated towards the applicator tip by 0.8mm (max=1.5mm). Mean difference between planned and RAL-measured channel lengths was 0.5 mm (max=0.9mm). On both RALs, more curved applicators had larger length deviations during commissioning and patient treatments. This increased curvature resulted in larger overestimates of channel length, up to 1.7mm for ovoids. Ovoid channel length deviations were similar for left and right ovoids on RAL1 at just over 1mm initially, and decreased over a 23 week period to be &lt;1mm. The deviations however remained steady for RAL2 over 10 weeks of treatment, with 90% of all values being &gt;1mm(Fig.1). Left ovoids showed larger deviation than right (1.45 vs 1.18mm respectively) (p&lt;0.01).&lt;/div&gt;&lt;","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":"23 6","pages":"Pages S60-S61"},"PeriodicalIF":1.7,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527205","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":"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}