Brachytherapy最新文献

{"title":"Saturday, July 13, 20248:00 AM - 9:00 AMMSOR01 Presentation Time: 8:00 AM","authors":"Aspazia Spyrou MB Bch BAO, MSc,MRCP , Helen Minnaar M.Insta.Pa , Yu Kai Shing Mphil, BSc , Jacqueline Steinke MBchB FRCS , Alexandra Stewart DM,MRCP,FRCR,FBIR","doi":"10.1016/j.brachy.2024.08.064","DOIUrl":"10.1016/j.brachy.2024.08.064","url":null,"abstract":"<div><h3>Purpose</h3><div>Although rectal cancers are traditionally treated with surgical excision, more patients are opting for alternatives and choosing an organ preservation approach instead.Studies demonstrate that a radiotherapy boost improves rates of complete response with low rates of regrowth.Contact X-Ray brachytherapy (CXB) often referred to as Papillon technique, accomplishes dose escalation in the treatment of low rectal cancer.This involves inserting an X-Ray tube through the anus and placing it in contact with the tumour. The OPERA study published in 2023, showed that for tumours <3cm in size, combination treatment of external beam radiotherapy(EBRT) and CXB boost achieves a 97% success rate of organ preservation within a 3-year follow up. St Luke's oncology Center is one of the 4 centers in the UK that specialise in Papillon brachytherapy. The <u>purpose</u> of this study was to report the toxicity of CXB; both alone and in combination with external beam radiotherapy (EBRT) as documented by patients themselves as a subset of our national colorectal patient reported outcome measures (PROMs) study CITRuS (<strong>C</strong>omplex <strong>I</strong>ntervention protocol <strong>T</strong>oxicity in patients following <strong>R</strong>adiotherapy or <strong>S</strong>urgery for colorectal cancer).</div></div><div><h3>Materials and Methods</h3><div>26 patients treated with CXB alone or in combination with EBRT were identified via the CITRuS platform(506 registered, 288 consented). 22 received CXB with EBRT (combined treatment) and 4 patients CXB alone. The CXB patients received no other treatment prior to CXB. The questionnaires investigated bowel, urinary and sleep symptoms as well as weight monitoring. The data presented reflect answers to the baseline questionnaires and up to the first 8 months post completion of treatment.This study is ongoing.</div></div><div><h3>Results</h3><div>Of the 22 patients who received the combined treatment, 19 completed the baseline questionnaires, 11 completed 4-5 months, 8 completed the 7-8 months period. In this group,two patients reported mild increase in their pain by the 5th month post treatment. <u>GI</u>: Six patients reported a slight increase in mucous from baseline to 5 months whereas three patients documented increase in nocturnal bowel symptoms. Futhermore, compared to baseline, patients reported an increase in flatulence, solid and liquid stool incontinence as well as their bowel motions affecting their lifestyle, at 5 months post treatment(16%).In the Papillon alone group, pain,blood,mucous and nocturnal symptoms were significantly improved by 5 months. Flatulence seems to be more predominant in this group around the 4-5 month period post treatment. <u>GU</u>:There was a definite peak in urine frequency in the combined group. The Papillon alone group showed improvement of all urinary symptoms by 4 months. <u>Sleep</u>:Both groups demonstrated a significant impact on their sleep quality","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527030","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":"GSOR12 Presentation Time: 5:55 PM","authors":"Sai Nikitha Prattipati MScGH ,&nbsp;Muhammad M. Qureshi MBBS, MPH ,&nbsp;Katrin Eurich MD ,&nbsp;Stephen Fiascone MD ,&nbsp;Andrea Negroiu MD ,&nbsp;Sherry X. Yan MD","doi":"10.1016/j.brachy.2024.08.058","DOIUrl":"10.1016/j.brachy.2024.08.058","url":null,"abstract":"<div><h3>Purpose</h3><div>We evaluated the utilization of adjuvant external beam radiation (EBRT) and vaginal brachytherapy (VBT) and the impact on survival benefit in stage IB to IVA uterine carcinosarcoma.</div></div><div><h3>Materials and Methods</h3><div>Patients with FIGO stage IB to IVA uterine carcinosarcoma who underwent hysterectomy and received adjuvant chemotherapy were identified from the National Cancer Database data from 2004 to 2017. The primary outcome of interest was overall survival based on adjuvant treatment modality: chemotherapy alone versus the addition of EBRT or VBT. Median survival was estimated using the Kaplan-Meier method, and the log-rank test was used to determine statistical significance. Adjusted hazard ratio (HR) with a 95% confidence interval (CI) was calculated using the multivariable Cox regression model. The model adjusted for following a priori selected covariates: age at diagnosis, race, year of diagnosis, insurance status, comorbidities, treatment facility type and pathologic stage.</div></div><div><h3>Results</h3><div>We identified 3038 patients diagnosed with uterine carcinosarcoma who met eligibility criteria (26% stage IB, 12% stage II, 19% stage IIIA/B, 41% stage IIIC, 3% stage IVA), of whom 1567 (51.6%) received adjuvant chemotherapy alone, 1046 (34.4%) received adjuvant EBRT with or without VBT, and 425 (14.0%) received adjuvant VBT. Patients who received radiation were younger; patients who received VBT were more likely to have earlier-stage disease, be treated at academic/research programs, and be white (all p &lt;0.001). With a median follow-up of 39 months, median survival was 32.7, 59.8, and 127.4 months for no adjuvant radiation, EBRT, and VBT, respectively (p &lt;0.001). The survival benefit of adjuvant radiation was maintained on multivariate analysis with HR 0.69 [0.62-0.76, p &lt;0.001) for EBRT and HR 0.58 [0.49-0.68], p &lt;0.001) for VBT (Table 1). The benefit of adjuvant radiation over chemotherapy alone persisted across all stages of uterine carcinosarcoma IB to IVA. Specifically, adjuvant EBRT improved survival in stage II to IVA, and adjuvant VBT improved survival in stage IB to IIIC.</div></div><div><h3>Conclusions</h3><div>Adjuvant radiation therapy, in addition to chemotherapy, improved overall survival in uterine carcinosarcoma. Adjuvant brachytherapy may be underutilized in this patient population.</div></div>","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527072","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":"PL02 Presentation Time: 1:45 PM","authors":"Christopher Deufel Ph.D.,&nbsp;Eric Brost Ph.D.,&nbsp;Justine Dupere Ph.D.,&nbsp;Ivy A. Petersen M.D.,&nbsp;Michael G. Haddock M.D.,&nbsp;Allison E. Garda M.D.","doi":"10.1016/j.brachy.2024.08.060","DOIUrl":"10.1016/j.brachy.2024.08.060","url":null,"abstract":"&lt;div&gt;&lt;h3&gt;Purpose&lt;/h3&gt;&lt;div&gt;To design, construct, and evaluate a system for assisted placement of brachytherapy applicators using electromagnetic tracking (EMT) technology that has been registered to CT or MRI images. The system provides real-time localization of needles during the insertion process, a three-dimensional display of planned needle sites, visibility of the anatomy and needle position during placement, and reference tracking to account for generator or target anatomy shifts. Such a system might be used to reduce brachytherapy procedure times, improve correspondence between intended and actual needle positions, or decrease the trainee learning curve. The system is notable for the following features: 1) Real-time visual and quantitative feedback of needle placement with respect to the underlying anatomy, as visualized by MRI or CT image, without continuous or repeated imaging 2) Pre-planning capability with a graphical overlay of target needle trajectories 3) Reference tracking to account for electromagnetic field generator or target anatomy shifts 4) DICOM-coordinate digital reconstruction of applicator locations for treatment planning and/or pre-treatment quality assurance 5) Compatibility with standard brachytherapy workflows including fixed table CT and MRI systems, procedures within or outside of a brachy suite, and insertion of needles in dorsal lithotomy position 6) Consists of commercially available EMT technology components&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Methods&lt;/h3&gt;&lt;div&gt;The system was constructed using an Aurora (Northern Digital Instruments, Waterloo, ON) planar 20 × 20 cm&lt;sup&gt;2&lt;/sup&gt; field generator (EFG), System Control Unit, Sensor Interface Unit, and 6DOF and 5DOF Flextube sensor tools. The graphical user interface was written as a Matlab application with native functions and toolboxes. EMT-to-DICOM registration was based upon intracavitary applicators (e.g., tandem and ovoids), placed prior to imaging and digitized automatically using thresholding methods. The EFG was positioned above the pelvis (Figure 1A), EMT sensors were translated through the tandem and ovoid channels, and the EMT system was registered to the DICOM image set using an iterative closest-point algorithm. Next, a 5DOF EMT sensor was loaded into the distal inner lumen of a brachytherapy needle for placement. The system display provides axial, coronal, sagittal, and 3D-volumetric CT/MRI views. Proof-of concept and system accuracy were evaluated in phantom and human cadaver by comparing EM-tracked needle positions with ground-truth, post-implant CTs.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Results&lt;/h3&gt;&lt;div&gt;Proof of concept was demonstrated for EMT-assisted placement of brachytherapy needles in a realistic clinical environment and on a brachy suite CT table. Figure 1B provides an example of how a pre-planned needle location (blue) can be visualized alongside real-time needle placement (red) to provide feedback to the user. The left-hand panel in Figure 1B shows an initial attempt where a ","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527074","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":"MSOR9 Presentation Time: 5:40 PM","authors":"Arjit Baghwala MS,&nbsp;ChengFeng Li MS,&nbsp;Forrest Ivey MS,&nbsp;Devin Olek MS,&nbsp;Kyle Harper MS,&nbsp;Ramiro Pino PhD,&nbsp;Andrew Farach MD","doi":"10.1016/j.brachy.2024.08.043","DOIUrl":"10.1016/j.brachy.2024.08.043","url":null,"abstract":"<div><h3>Purpose</h3><div>In a radiation oncology (RO) clinic, brachytherapy (BT) is a time and resource intensive modality. Constraints to efficiency and throughput include physical resources: afterloader and vault availability, applicator inventory, and OR availability but also physician and support staff availability to maintain efficiency. Thus, several things need to be considered when scheduling cases and having a BT team with each member given their defined roles is essential. The goal of utilizing a BT procedure daily scorecard is to ensure adequate resource allocation and minimize the risk of burnout that could potentially lead to employee dissatisfaction, patient safety events, or turnover on the BT team. Utilizing a similar scorecard method will also be useful to radiation oncologists and RO clinics worldwide when starting or grow a BT program.</div></div><div><h3>Methods</h3><div>Each BT procedure was given a score ranging from 1 - 3 (Table 1) based on complexity. A score of 1 was allocated to procedures that were relatively less labor intensive. A score of 2 was given to procedures that required a treatment plan on the day of implant and nursing care. A score of 3 was given to procedures that required BT team members to be in the OR for pre-procedure setup and implantation or implants with longer procedural, treatment planning, and delivery times. The total BT score was limited to no more than 10 on any given day when creating a BT schedule with additional review required for schedules exceeding a score of 10 to allow for appropriate staffing. A retrospective analysis was performed analyzing the number of cases, average start/end time, the average BT score, and the average difficulty per case for 3 months pre-implementation and 3 months post-implementation.</div></div><div><h3>Results</h3><div>Implementing a daily BT procedural scorecard improved BT procedural efficiency without compromising procedural throughput. Despite maintaining a similar average difficulty of cases performed (1.85 vs 1.78 ±0.47), the clinic time spent in BT was reduced along with the score of the day (9.1 vs 6.87). Utilizing the scoring system may also improve BT team morale due to decreased daily case complexity, shortened hours, and through appropriate procedural staffing.</div></div><div><h3>Conclusion</h3><div>We show utilizing a BT scoring system can improve efficiency of BT workflow without compromising patient throughput. Strategies such as this may help BT clinics improve schedule organization, employee satisfaction, staffing models, and should be considered in all high-volume BT clinics.</div></div>","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527076","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":"PPP02 Presentation Time: 10:39 AM","authors":"Vitaly A. Biryukov MD, PhD ,&nbsp;Elizaveta O. Shchukina MD ,&nbsp;Natalia B. Ermakova PhD ,&nbsp;Dmitry B. Sanin PhD ,&nbsp;Olga G. Lepilina PhD ,&nbsp;Oleg B. Karyakin (Prof.) ,&nbsp;Sergey A. Ivanov (Prof.) ,&nbsp;Andrey D. Kaprin (Prof.)","doi":"10.1016/j.brachy.2024.08.010","DOIUrl":"10.1016/j.brachy.2024.08.010","url":null,"abstract":"<div><div>In the Russian Federation the number of patients with prostate cancer in stage I-II has increased from 48.4% to 63.0% over the past 10 years (2012 - 2022). It is the second most common cancer in men after lung cancerin 2021 in Russia. One of the most common methods of treating localized prostate cancer is brachytherapy. In the Department of radiation and surgical treatment of urological diseases with the prostate cancer brachytherapy group of the A.F.Tsyb MRRC, HDR-BT as monotherapy has been performed since 2016 with the use of Ir-192.</div></div><div><h3>Purpose</h3><div>Compare the efficiency of modes of HDR-BT with the use of Ir-192 in the treatment of localized prostate cancer.</div></div><div><h3>Materials and Methods</h3><div>In the study the review is given to the results of treatment of patients with localized prostate cancer of low and intermediate risk progression groups who were treated at the A.F.Tsyb MRRC from April 2016 to December 2019. 276 patients were randomized to receive HDR-BT as either a single fraction of 19 Gy or as two fractions of 15 Gy two week apart. The number of patients in the 2 × 15 Gy group was 146, in the 1 × 19 group - 130. The characteristics of the patients are presented in Table 1. Brachytherapy was performed with the use of Ir-192 under spinal anesthesia. Follow-up included a TRUS of prostate, recording of toxicity, and measurement of serum PSA. Patients with biochemical failure (nadir + 2 ng/ml) or clinical suspicion of recurrence were investigated with multiparametric MRI of prostate, and PSMA-PET. Any radiographic suspicion of local recurrence was confirmed on biopsy.</div></div><div><h3>Results</h3><div>Biochemical relapse was documentedin32 patients: 5 patients in group 15 Gy х 2 and 27 patients in group 19 Gy. The dependence of the risk of relapse on the HDR-BT mode, estimated using the Mantel-Cox log-rank criterion, was statistically significant (p&lt;0.001). The analysis performed using the Kaplan-Meyer method showed that the average time of recurrence among patients who received 2 fractions of HDR-BT was 88.25±1.77 months (95% CI: 84.78 - 91.72), among patients who received one fraction of HDR-BT - 67.45±1.98 (95% CI: 63.58 - 71.32). The median was not reached in both groups of patients.</div></div><div><h3>Conclusions</h3><div>In conclusion, HDR monotherapy delivered as two fraction of15 Gy have a high cancer control rate than as one fraction of 19 Gy. Single fraction monotherapy provides inferior results and is not used in our center now.</div></div>","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142526546","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":"GSOR03 Presentation Time: 5:10 PM","authors":"Santanu Samanta MD ,&nbsp;Emily Baker MA ,&nbsp;Anam Kesaria MD ,&nbsp;Haley Kelly RN ,&nbsp;Faraz K. Mahmoudabadi PhD ,&nbsp;Gary Lewis MD","doi":"10.1016/j.brachy.2024.08.049","DOIUrl":"10.1016/j.brachy.2024.08.049","url":null,"abstract":"<div><h3>Purpose</h3><div>Brachytherapy using HDR plays a crucial role in the treatment of gynecological cancer undergoing radiation therapy. This pilot study examines the use of Virtual Reality (VR) distraction for subjects undergoing HDR brachytherapy and its effects on their satisfaction, procedural anxiety, pain, and the need for analgesics or anxiolytics. We hypothesize that incorporating VR distraction into the brachytherapy treatment workflow will improve subjects’ satisfaction, reduce procedural anxiety and pain, and reduce the need for analgesics or anxiolytics.</div></div><div><h3>Methods and Materials</h3><div>From September 2022 to November 2023, 7 patients have been enrolled so far, each requiring a minimum of 4 sessions of HDR brachytherapy. Each patient underwent 2 sessions with VR and 2 sessions without. Each patient was also asked to fill out a questionnaire before and after each HDR brachytherapy session, which included pain score, and anxiety score among other details. Data including AE events were recorded post-treatment for all sessions.</div></div><div><h3>Results</h3><div>With an accrual goal of 20 patients, 7 women, ages 29 to 81, participated in the study. Six of the subjects were white and 1 subject was black or African American. All 7 subjects attempted to use virtual reality during brachytherapy at least once, contributing to a total of 12 sessions with virtual reality, which were compared to 13 complete sessions without virtual reality. The preliminary results show the following. Subjects reported lower average pre-procedural pain prior to VR sessions. 2. Subjects reported lower average procedural pain during VR sessions. 3. Subjects reported about the same pre-procedural anxiety with or without virtual reality 4. Subjects reported a high satisfaction score and would like to use the VR again.</div></div><div><h3>Conclusions</h3><div>These preliminary results suggest a potential reduction in procedural pain with the inclusion of VR sessions during HDR brachytherapy. However, there was no observed change in the need for opioid or anxiety medications among these initially enrolled patients. All subjects reported high satisfaction scores and would like to use VR again. While many subjects reported it was their first time engaging with VR, in the future, we plan to incorporate a longer demo session and modify the questionnaire to improve the subject's familiarity with the technology.</div></div>","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527133","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":"MSOR4 Presentation Time: 5:15 PM","authors":"Tomer Cooks PhD ,&nbsp;Yossi Nishri PhD ,&nbsp;Maayan Vatarescu PhD ,&nbsp;Ishai Luz PhD ,&nbsp;Lior Epstein PhD ,&nbsp;Mirta Dumančić PhD ,&nbsp;Sara Del Mare PhD ,&nbsp;Amit Shai MSc ,&nbsp;Michael Schmidt PhD ,&nbsp;Lisa Deutsch PhD ,&nbsp;Robert B. Den MD ,&nbsp;Itzhak Kelson PhD ,&nbsp;Yona Keisari PhD ,&nbsp;Lior Arazi PhD ,&nbsp;Vered Domankevich PhD","doi":"10.1016/j.brachy.2024.08.038","DOIUrl":"10.1016/j.brachy.2024.08.038","url":null,"abstract":"&lt;div&gt;&lt;h3&gt;Purpose&lt;/h3&gt;&lt;div&gt;Diffusing alpha-emitters radiation therapy (DaRT) is a unique treatment modality for solid tumors capitalizing on Radium-224-loaded (Alpha DaRT) sources designed to disperse alpha-emitting atoms into the tumor tissue. These diffused radioactive atoms create a destructive 'kill-zone' millimeters away from the source, without harming adjacent tissue. This treatment was reported to effectively inhibit tumor growth in various human and murine cancers in pre-clinical testing. Here, the effect of Alpha DaRT was investigated &lt;em&gt;in-vitro&lt;/em&gt; and &lt;em&gt;in-vivo&lt;/em&gt; using subcutaneous (s.c.) Glioblastoma Multiforme (GBM) tumors in combination with GBM ‘standard of care’ treatments (Temozolomide, TMZ or Bevacizumab, BEV). We also studied the effect of the Alpha DaRT monotherapy in orthotopic GBM tumors.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Methods and Materials&lt;/h3&gt;&lt;div&gt;The effect of alpha radiation with TMZ was evaluated in human U87 cells by cytotoxicity and colony formation assays. VEGF secretion was assessed using ELISA assay. U87 s.c. tumor-bearing mice were treated with Alpha DaRT or inert (non-radioactive) sources in combination with TMZ or BEV, and monitored for efficacy. To assess tumor vasculature, we performed immunohistochemical staining of the vascular marker CD31. Alpha DaRT effective diameter receiving high dose (&gt;10 Gy) was determined by autoradiography. The clearance of radioactive atoms from the tumor was determined by radioactivity measurements of the tumor and source 4 days post implantation compared with the initial activity. Murine GL-261 GBM cells were used for the inoculation of orthotopic GBM, and their growth was monitored using MRI before they were treated with Alpha DaRT or Inert sources.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Results&lt;/h3&gt;&lt;div&gt;The combined treatment of alpha radiation and TMZ doubled the cytotoxic effect compared to the monotherapies. U87 cells treated with the combined treatment showed lower survival fraction than the monotherapies or than x-ray combined with TMZ treatment. U87 s.c. tumor bearing mice treated with Alpha DaRT and TMZ showed increased delay in tumor growth compared to the monotherapies. Unlike other radiation types, alpha radiation did not increase VEGF secretion by U87 cells. As expected, BEV administration decreased CD31 staining and when combined with Alpha DaRT, the effective diameter was increased and the clearance of the radioactivity was reduced. &lt;em&gt;In-vivo&lt;/em&gt; studies showed that administration of BEV a few days after Alpha DaRT insertion improved tumor control - in comparison to Alpha DaRT or BEV alone. Improved results were obtained in larger tumors when the BEV protocol was initiated before the Alpha DaRT insertion. We were able to establish an orthotopic model of GBM and fabricate a designated Alpha DaRT applicator and source suitable for mice brains. We successfully monitored tumor growth and Alpha DaRT insertion using MRI as well as in-vivo real-time imager.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Conclusion","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142526609","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":"GPP05 Presentation Time: 11:06 AM","authors":"Thomas Niedermayr PhD,&nbsp;Elizabeth Kidd MD","doi":"10.1016/j.brachy.2024.08.091","DOIUrl":"10.1016/j.brachy.2024.08.091","url":null,"abstract":"&lt;div&gt;&lt;h3&gt;Purpose&lt;/h3&gt;&lt;div&gt;The disease control and toxicity benefits of adding interstitial needles to cervix intracavitary implants are well established, as are the advantages of MRI for tumor visualization. Yet widespread adoption of these advanced techniques remains elusive, limited by access to frequent MR imaging and the technical challenges of precisely placing needles into the tumor. Ultrasound (US) remains the most accessible form of live imaging but the poorer image quality limits clear visualization of the tumor area and the inserted interstitial needles. We describe a novel system which combines a freehand, stepper-less transrectal ultrasound probe with an electro-magnetic (EM) tracker to continuously fuse a pre-acquired MR, offering a reconstructed MR image to the corresponding live ultrasound image. Inserted needles can be easily visualized using an EM tracked stylet/mandrin, placing a solid circle on the live ultrasound image where the needle is located.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Materials and Methods&lt;/h3&gt;&lt;div&gt;The clinical ultrasound system, the BK Spekto with a biplanar side-fire 9048 US probe, was instrumented with a Northern Digital Inc. EM tracker, part of the 3D Guidance Trakstar system. Software was developed using the 3D Slicer toolkit to enable live and continuous fusion of a pre-acquired MR. Contours generated on the MR can be imported and displayed on the live US image. An additional EM tracker can be placed inside a needle to visualize its location on the live US image and removed for treatment.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Results&lt;/h3&gt;&lt;div&gt;The system was assessed on a Viomerse Gyn phantom before being deployed in clinical implants (Fig 1A). Initial registration between the live US image and the MR is accomplished by placing the freehand transrectal US probe within the patient to a known location, such as the top of the vaginal canal/cervix area. The corresponding MR/US fusion is then locked, any movement of the freehand probe will update both the US and MR images correspondingly. Fine tuning of the registration can be done in all six degrees of freedom as necessary to accommodate any shifts and/or deformations during the procedures. Needles can easily be identified on the live US when a stylet equipped with a miniature EM tracker is inserted: a yellow circle appears on the live US at the intersection on the imaging plane where the needle is expected (Fig 1B). In case of multiple needles, the trajectory of each needle can be digitally saved within the EM frame of reference, providing a colored mark where each needle was placed on the live US. HR-CTV contours can be overlaid on the live US to help highlight the area of interest (Fig 1C).&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Conclusion&lt;/h3&gt;&lt;div&gt;A novel system has been developed and clinically tested to enhance the capabilities of US imaging for gyn brachytherapy procedures by incorporating clarifying MR information and easy needle recognition. These features can help guide the practitioner during the proce","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527284","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":"PHSOR02 Presentation Time: 9:05 AM","authors":"Mathieu Goulet PhD ,&nbsp;Patricia Duguay-Drouin MSc ,&nbsp;Julien Mégrourèche MSc ,&nbsp;Nadia Octave PhD ,&nbsp;James M. Tsui BEng, MSc, MDCM, PhD","doi":"10.1016/j.brachy.2024.08.076","DOIUrl":"10.1016/j.brachy.2024.08.076","url":null,"abstract":"&lt;div&gt;&lt;h3&gt;Purpose&lt;/h3&gt;&lt;div&gt;High dose rate (HDR) prostate brachytherapy (BT) procedure requires imaging to guide transperineal needle insertion, either with CT, MR, or ultrasound (US) imaging. US is occasionally favored for its streamlined workflow and when access to other imaging is limited. General anesthesia is often used throughout the procedure, thus minimizing overall planning time is crucial to mitigate potential complications and allow for better management of operating room time. In this study, we explore the accuracy and time-saving potential of AI-driven auto-reconstruction of transperineal needles in the context of US-guided prostate BT planning.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Materials and Methods&lt;/h3&gt;&lt;div&gt;A total of 98 US BT cases from a single institution were used in this work. US images were acquired using a BK3000 US + E14CL4b endocavity biplane transducer and combined into 3D-US datasets using the Oncentra Prostate system from Elekta. Gray value histogram of each 3D-US image was normalized. The data was split into 3 groups: 50 for training and validation (training set), 11 to evaluate reconstruction accuracy (test set #1) and 37 to evaluate the AI tool in a clinical implementation (test set #2). A 3D-UNet machine learning network was used, using human-reconstructed needles during the BT procedure as the reference segmentation mask. Model training was performed using the PyTorch library version 2.0.1 on a NVIDIA Quadro RTX 6000 GPU using Dice loss and AdamW optimizer. A 10-fold cross-validation scheme was employed during training. Reconstruction accuracy for test set #1 was evaluated by having 4 medical physicists manually reconstructing needles on the 3D-US scan after treatments. Ground truth reference needle positions for each observer (AI included) were determined from the other 4 reconstructions using a weighted voting average inspired by the STAPLE algorithm. Reconstruction accuracy was evaluated by taking the root mean squared error from the center of each reconstructed needle to the center of the ground truth needle, on each image axial slice in which the needle was visible by both humans and AI. Interobserver variability was evaluated using one-way ANOVA and Tukey's HSD post-hoc test. The needle total reconstruction time for test set #2 was taken as the timestamp difference from scan acquisition to final modification of the plan before dose calculations. This value was compared to values of the 50 cases done before the clinical implementation of the AI-assisted tool using a two-sample z-test. For this phase, we also measured the true positive rate of needle reconstruction and the # of AI-reconstructed needles that were further adjusted by the human planner.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Results&lt;/h3&gt;&lt;div&gt;A mean error of (0.47±0.31) mm was found between the AI-reconstructed and the ground truth needles in test set #1, with 95.2% of AI needle points falling below 1 mm from their human-made counterparts. One-way ANOVA showed statistical difference","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527290","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":"BP02 Presentation Time: 4:09 PM","authors":"Birte Christina Sauer (M. Sc.),&nbsp;Rainer Fietkau (Prof. Dr. Med.),&nbsp;Vratislav Strnad (Dr. med.),&nbsp;Christoph Bert (Prof. Dr.),&nbsp;Christopher Dürrbeck Dr.","doi":"10.1016/j.brachy.2024.08.026","DOIUrl":"10.1016/j.brachy.2024.08.026","url":null,"abstract":"<div><h3>Purpose</h3><div>Interstitial brachytherapy of the breast is a well-established treatment option with very good clinical results. However, it is prone to human failures according to several safety reports [1-4], indicating that a timely detection and prevention of treatment errors is advised. An extensive patient specific quality assurance procedure could be implemented using electromagnetic tracking (EMT), which has shown its potential by enabling a line-of-sight independent and dose free tracing of implanted catheters or needles.</div></div><div><h3>Materials and Methods</h3><div>We retrospectively analyzed and categorized potential treatment errors in a cohort of 72 patients comprising more than 580 fractions and more than 8000 catheters. All patients were treated between October 2016 and November 2023 and participated in our EMT study. The implant geometry was assessed after each treatment fraction and after the planning CT by means of EMT. The detection and classification of errors is based on deviations between expected and measured catheter positions.</div></div><div><h3>Results</h3><div>Concerning planning errors, we did not find any (partial) swaps, but detected one inversion of the reconstruction direction (tip-end-swap). Before treatment delivery, we detected shifts larger than 0.8 mm in 35 % of all measured catheters, out of which 50 % were &gt; 2 mm, 15 % were &gt; 5 mm and 2 % were &gt; 10 mm. The highest recorded shift reached 21.9 mm, the median magnitude was 3.0 mm. Delivery errors also included three swaps of neighboring catheters that were visually verified. It should be noted that the EMT enabled afterloader does not carry an active source, therefore, the transfer tubes had to be manually reconnected. This means that the detected swaps may not represent the clinical state, however, they provide an estimate for the probability of swaps to occur in clinical practice.</div></div><div><h3>Conclusions</h3><div>This study presents a first of its kind systematic treatment error analysis. It emphasizes the necessity for a patient specific quality assurance and treatment verification in interstitial breast brachytherapy to prevent potential errors, especially in view of ever shorter fractionation schemes.</div></div>","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142526712","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}