Brachytherapy最新文献_第3页

Multicenter study on mechanical accuracy of short dwell time and source transit for HDR Ir-192 brachytherapy treatment machine HDR Ir-192近距离放射治疗机短停留时间和光源传输机械精度的多中心研究。

IF 1.8 4区医学 Q4 ONCOLOGY

Brachytherapy

Pub Date : 2026-01-01 Epub Date: 2025-11-11 DOI: 10.1016/j.brachy.2025.09.018

Yoshihiro Ueda , Hiroyuki Okamoto , Yoshifumi Oku , Yasushi Ono , Jun Takatsu , Jun-ichi Fukunaga , Takahiro Ushijima , Masahiko Toyota , Kotaro Iijima , Naoya Murakami , Tatsuya Ohno

PURPOSE

To evaluate the accuracy of the effective transit and dwell times for high-dose-rate (HDR) brachytherapy machines across multiple institutions. The aim was to establish reference levels for quality assurance (QA) in MicroSelectron and Flexitron afterloaders.

METHODS

The effective transit time of the amount of charge from the moving source divided by the current value and the short dwell times were measured using institution-owned well-type ionization chambers for 11 treatment machines from 10 institutions, including MicroSelectron and Flexitron afterloaders. Measurements were performed under standardized conditions to minimize variability, including controlled distances from walls and floors to reduce scattered radiation. The proportionality constants and effective transit times were calculated and the dwell times were measured for settings ranging from 0.1 to 30 s. For each afterloader, effective transit time and dwell time accuracy were measured five times, and the averages were used for analysis.

RESULTS

MicroSelectron afterloaders exhibited mean effective transit times of 0.90–1.05 s, whereas Flexitron afterloaders showed shorter times of 0.54–0.62 s. For the dwell time accuracy, MicroSelectron afterloaders exhibited a mean error of −0.048 to 0.104 s, with larger variability across institutions. In contrast, Flexitron afterloaders showed a mean error consistently below ±0.01 s, even at shorter dwell times. The variability in dwell time was notably significant higher for MicroSelectron than for Flexitron afterloaders (p ≤ 0.002).

CONCLUSIONS

This study demonstrates clear performance differences between MicroSelectron and Flexitron afterloaders in HDR brachytherapy and provides reference levels that support device-specific QA protocols to improve treatment precision and ensure consistent outcomes across institutions.

目的：评估跨多个机构的高剂量率（HDR）近距离放疗机有效传输和停留时间的准确性。目的是建立MicroSelectron和Flexitron后装载机质量保证（QA）的参考水平。方法：采用机构自备的井式电离室，对MicroSelectron和Flexitron等10家机构的11台处理设备进行了移动源电荷量除以电流值的有效传递时间和短停留时间的测量。测量是在标准化条件下进行的，以尽量减少变化，包括控制与墙壁和地板的距离，以减少散射辐射。计算了比例常数和有效传递时间，并测量了0.1至30 s范围内的停留时间。对于每个后装机，有效传递时间和停留时间精度测量了五次，并使用平均值进行分析。结果：MicroSelectron后装载机的平均有效传递时间为0.90 ~ 1.05 s， Flexitron后装载机的平均有效传递时间为0.54 ~ 0.62 s。对于停留时间精度，MicroSelectron后装器的平均误差为-0.048至0.104 s，不同机构的差异较大。相比之下，Flexitron后装载机的平均误差始终低于±0.01 s，即使在较短的停留时间。MicroSelectron的停留时间变异性显著高于Flexitron （p ≤ 0.002）。结论：本研究证明了MicroSelectron和Flexitron后置器在HDR近距离治疗中的明显性能差异，并提供了支持设备特定QA协议的参考水平，以提高治疗精度并确保各机构的一致结果。

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引用次数: 0

Automatic digitization of applicator and catheters for MRI-guided cervical cancer brachytherapy mri引导下宫颈癌近距离放疗应用器和导管的自动数字化。

IF 1.8 4区医学 Q4 ONCOLOGY

Brachytherapy

Pub Date : 2026-01-01 Epub Date: 2025-11-06 DOI: 10.1016/j.brachy.2025.09.017

Gayoung Kim , Majd Antaki , Ehud J. Schmidt , Michael Roumeliotis , Akila N. Viswanathan , Junghoon Lee

PURPOSE

MRI is the standard imaging modality for contouring organs-at-risk and clinical target volume in cervical cancer brachytherapy, and is widely used along with CT for treatment planning and image guidance. However, MRI-CT fusion-based approach is time-consuming and error-prone as it requires two imaging sessions and image registration. To realize more efficient and streamlined MRI-guided workflow, we propose an automatic method for digitizing the applicator and catheters using MRI alone.

METHODS

Applicator digitization consists of applicator mesh reconstruction, applicator ring identification, and alignment of the mesh model with MRIs. For catheter digitization, we employ an uncertainty-aware deep-learning model that simultaneously segments catheters and computes uncertainty on its prediction. These uncertainty facilitate initial localization of the catheters and subsequent refinement.

RESULTS

This study was performed on 35 T2-weighted MRIs from 30 cervical cancer patients treated with the Venezia applicator. The dataset was divided into 80% for development and 20% for testing. The method successfully digitized all applicators, with mean translation and rotation errors of 1.13 ± 0.26 mm and 2.19 ± 2.09°, respectively. All catheters except one were successfully digitized with shaft and tip errors of 0.74 ± 0.32 mm and 2.52 ± 2.04 mm, respectively. Furthermore, plans derived from the automatic digitization showed no significant differences compared to clinical plans (p > 0.05).

CONCLUSION

The proposed MRI-based applicator and catheters digitization simplifies the brachytherapy planning process by eliminating the need for CT and manual tasks. Our results demonstrate that this approach is feasible and can be integrated into clinical workflows, offering potential improvements in efficiency and accuracy.

目的：MRI是宫颈癌近距离放疗中高危器官和临床靶体积轮廓的标准成像方式，与CT一起广泛应用于治疗计划和图像指导。然而，基于MRI-CT融合的方法耗时且容易出错，因为它需要两次成像和图像配准。为了实现更高效和简化的MRI引导工作流程，我们提出了一种仅使用MRI就能自动数字化涂药器和导管的方法。方法：涂布器数字化包括涂布器网格重建、涂布器环识别和网格模型与mri对齐。对于导管数字化，我们采用了一种不确定性感知深度学习模型，该模型可以同时分割导管并计算其预测的不确定性。这些不确定性有助于导管的初始定位和随后的细化。结果：本研究对30例使用Venezia涂抹器治疗的宫颈癌患者的35例t2加权mri进行了研究。数据集分为80%用于开发，20%用于测试。该方法成功实现了所有涂药器的数字化，平均平移和旋转误差分别为1.13 ± 0.26 mm和2.19 ± 2.09°。除1根导管外，其余导管均数字化成功，轴和尖端误差分别为0.74 ± 0.32 mm和2.52 ± 2.04 mm。此外，自动数字化方案与临床方案相比无显著差异（p > 0.05）。结论：提出的基于mri的涂药器和导管数字化，通过消除对CT和人工任务的需要，简化了近距离治疗计划过程。我们的研究结果表明，这种方法是可行的，可以整合到临床工作流程中，在效率和准确性方面提供潜在的改进。

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引用次数: 0

Assessment of brachytherapy-induced prostate edema on postimplant dosimetric analysis in patients treated with magnetic resonance imaging–assisted radiosurgery (MARS) 在接受磁共振成像辅助放射手术（MARS）治疗的患者中，近距离治疗引起的前列腺水肿的剂量学分析评估。

IF 1.8 4区医学 Q4 ONCOLOGY

Brachytherapy

Pub Date : 2026-01-01 Epub Date: 2025-11-20 DOI: 10.1016/j.brachy.2025.09.005

Kathryn E. Marqueen , Kelsey L. Corrigan , Surendra Prajapati , Rajat J. Kudchadker , Gohar Manzar , Elaine Cha , Henry Mok , Chad Tang , Comron Hassanzadeh , Osama Mohamad , Steven J. Frank

Purpose

Brachytherapy-induced prostate edema (PE) can result in altered target dose coverage in prostate cancer patients treated with low-dose-rate (LDR) brachytherapy. While visualization of PE on CT is limited, PE is evident on magnetic resonance imaging (MRI) day 0 (D0) postimplant assessment, a critical step in the MRI-assisted radiosurgery (MARS) framework that improves LDR brachytherapy quality assurance. This study investigated PE in patients treated with MARS to analyze the effect on postimplant dosimetry and further optimize the treatment-planning process.

Materials and Methods

We identified 317 patients with low-risk to intermediate-risk prostate cancer treated with cesium-131, iodine-125, or palladium-103 MARS definitive monotherapy from 2016 to 2021. Postimplant dosimetry was performed using MRI on D0. Simple linear regression with Pearson correlation analysis and ordinary ANOVA were used for analysis.

Results

The median D0 prostate volume was 29% higher (IQR, 16%–42%) compared with preimplant measurement, with no significant differences in PE magnitude by isotope (p = 0.33) or number of needles implanted (p = 0.70). PE magnitude decreased with increasing preplan prostate size (p < 0.001). Greater PE was associated with decreased D0 prostate V₁₀₀ (p < 0.001), V₁₅₀ (p < 0.001), and D₉₀ (p < 0.001), but was not associated with V₂₀₀ (p = 0.06), and >98% implants achieved D₉₀/prescription dose >90%. Greater PE was associated with decreased rectum V₁₀₀ (p = 0.02).

Conclusions

MRI on D0 confirmed PE after LDR brachytherapy. PE was not significantly different between isotopes, supporting the use of the same preplan target-volume margins among isotopes. Greater PE was associated with decreased prostate V₁₀₀, V₁₅₀, and D₉₀, without significant impact on overall implant quality.

目的：近距离放疗引起的前列腺水肿（PE）可导致低剂量率（LDR）近距离放疗前列腺癌患者靶剂量覆盖的改变。虽然PE在CT上的可视化是有限的，但PE在植入后的磁共振成像（MRI）第0天（D0）评估中是明显的，这是MRI辅助放射外科（MARS）框架中提高LDR近距离治疗质量保证的关键步骤。本研究调查了MARS患者的PE，分析其对植入后剂量学的影响，进一步优化治疗计划流程。材料和方法：我们从2016年至2021年确定了317例接受铯-131、碘-125或钯-103 MARS确定性单药治疗的低风险至中风险前列腺癌患者。采用MRI对D0进行注射后剂量测定。采用简单线性回归结合Pearson相关分析和普通方差分析进行分析。结果：与植入前测量值相比，中位D0前列腺体积增加29% (IQR, 16%-42%)，同位素PE大小（p = 0.33）或植入针数（p = 0.70）无显著差异。PE大小随预计划前列腺大小的增加而降低(p 100 (p 150)(p 90 (p 200)(p = 0.06),>98%植入物达到D90/处方剂量>90%。PE增大与直肠V100降低相关（p = 0.02）。结论：LDR近距离治疗后，D0 MRI证实PE。不同同位素之间的PE没有显著差异，支持在同位素之间使用相同的预计划目标体积边界。较大的PE与前列腺V100、V150和D90降低相关，但对整体植入物质量无显著影响。

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引用次数: 0

Combined operative and radiotherapeutic treatment for locally recurrent gynaecologic cancer with pelvic wall invasion: A monocentric retrospective study 手术与放疗联合治疗局部复发妇科癌伴盆腔壁侵犯：单中心回顾性研究。

IF 1.8 4区医学 Q4 ONCOLOGY

Brachytherapy

Pub Date : 2026-01-01 Epub Date: 2025-10-16 DOI: 10.1016/j.brachy.2025.09.003

Selnur Özkurt , Eva Oldenburger , Vincent Tambeur , Laurence Delombaerde , Thaïs Baert , Ignace Vergote , Toon Van Gorp , Els Van Nieuwenhuysen , Marisol De Brabandere , An Nulens , Hilde Janssen , Erik Van Limbergen , Melissa Christiaens

INTRODUCTION

Managing locally recurrent gynecologic cancer with pelvic wall invasion, particularly after prior pelvic radiotherapy, presents a significant clinical challenge. Combined operative and radiotherapeutic treatment (CORT) is a potential curative approach. This study aims to evaluate the effectiveness and morbidity of this technique in this patient population as implemented within a single institution.

METHODS AND MATERIALS

A comprehensive, retrospective analysis was conducted on patients treated with CORT for recurrent gynecologic cancer with pelvic wall invasion after prior pelvic radiotherapy at the University Hospitals of Leuven between January 2000 and December 2023.

RESULTS

A total of 21 patients were eligible for analysis. All patients underwent open surgical macroscopic tumor resection with intraoperative implantation of brachytherapy guiding tubes. The average radiation dose to 90% of the treatment volume (D90) was 45.6 Gy EQD2 (range 16.0 to 66.2 Gy). The median follow-up period was 37.8 months (range 3–230 months). Local control at 2 and 5 years was 87,4% and 77,8%; overall-survival at 2 and 5 years was 57,1% and 52,4%, respectively. Seventeen of the 21 patients experienced some form of adverse event, with 15 patients needing surgical re-intervention.

CONCLUSIONS

Our retrospective analysis demonstrates high local control and favorable overall-survival outcomes in patients with recurrent gynecologic cancer involving the pelvic wall. However, the treatment is associated with a substantial risk of severe adverse events. Given the complexity and potential morbidity of this approach, CORT should be performed in specialized centers with experience in managing such cases.

导言：治疗局部复发的妇科癌伴盆腔壁侵犯，特别是先前盆腔放疗后，是一个重大的临床挑战。手术和放疗联合治疗（CORT）是一种潜在的治疗方法。本研究旨在评估该技术在单个机构内实施的患者群体中的有效性和发病率。方法与材料：对2000年1月至2023年12月在鲁汶大学医院接受CORT治疗的既往盆腔放疗后盆腔壁侵犯的复发性妇科癌症患者进行全面回顾性分析。结果：共有21例患者符合分析条件。所有患者均行开放手术肉眼肿瘤切除术，术中置入近距离引导管。占治疗量90%的平均辐射剂量（D90）为45.6 Gy EQD2（范围16.0 ~ 66.2 Gy）。中位随访期为37.8个月（3-230个月）。2年和5年局部控制率分别为87.4%和77.8%；2年和5年的总生存率分别为57.1%和52.4%。21例患者中有17例出现了某种形式的不良事件，15例患者需要手术再干预。结论：我们的回顾性分析显示，累及骨盆壁的复发性妇科癌症患者具有较高的局部控制性和良好的总体生存预后。然而，这种治疗与严重不良事件的重大风险相关。考虑到这种方法的复杂性和潜在的发病率，CORT应该在有处理此类病例经验的专业中心进行。

{"title":"Combined operative and radiotherapeutic treatment for locally recurrent gynaecologic cancer with pelvic wall invasion: A monocentric retrospective study","authors":"Selnur Özkurt , Eva Oldenburger , Vincent Tambeur , Laurence Delombaerde , Thaïs Baert , Ignace Vergote , Toon Van Gorp , Els Van Nieuwenhuysen , Marisol De Brabandere , An Nulens , Hilde Janssen , Erik Van Limbergen , Melissa Christiaens","doi":"10.1016/j.brachy.2025.09.003","DOIUrl":"10.1016/j.brachy.2025.09.003","url":null,"abstract":"<div><h3>INTRODUCTION</h3><div>Managing locally recurrent gynecologic cancer with pelvic wall invasion, particularly after prior pelvic radiotherapy, presents a significant clinical challenge. Combined operative and radiotherapeutic treatment (CORT) is a potential curative approach. This study aims to evaluate the effectiveness and morbidity of this technique in this patient population as implemented within a single institution.</div></div><div><h3>METHODS AND MATERIALS</h3><div>A comprehensive, retrospective analysis was conducted on patients treated with CORT for recurrent gynecologic cancer with pelvic wall invasion after prior pelvic radiotherapy at the University Hospitals of Leuven between January 2000 and December 2023.</div></div><div><h3>RESULTS</h3><div>A total of 21 patients were eligible for analysis. All patients underwent open surgical macroscopic tumor resection with intraoperative implantation of brachytherapy guiding tubes. The average radiation dose to 90% of the treatment volume (D90) was 45.6 Gy EQD2 (range 16.0 to 66.2 Gy). The median follow-up period was 37.8 months (range 3–230 months). Local control at 2 and 5 years was 87,4% and 77,8%; overall-survival at 2 and 5 years was 57,1% and 52,4%, respectively. Seventeen of the 21 patients experienced some form of adverse event, with 15 patients needing surgical re-intervention.</div></div><div><h3>CONCLUSIONS</h3><div>Our retrospective analysis demonstrates high local control and favorable overall-survival outcomes in patients with recurrent gynecologic cancer involving the pelvic wall. However, the treatment is associated with a substantial risk of severe adverse events. Given the complexity and potential morbidity of this approach, CORT should be performed in specialized centers with experience in managing such cases.</div></div>","PeriodicalId":55334,"journal":{"name":"Brachytherapy","volume":"25 1","pages":"Pages 56-62"},"PeriodicalIF":1.8,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145314290","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}

引用次数: 0

Development of a phantom and analysis of brachytherapy dosimetry using the sulfamic acid/electron paramagnetic resonance system 使用胺磺酸/电子顺磁共振系统的近距离放射治疗剂量学的幻影和分析。

IF 1.8 4区医学 Q4 ONCOLOGY

Brachytherapy

Pub Date : 2026-01-01 Epub Date: 2025-11-07 DOI: 10.1016/j.brachy.2025.10.002

Ghizlane Boukhris , Mohammed Mikou , Omar El Rhazouani , Redouane El Baydaoui , Sofia Jebbari , Abdeslam Bouk , Dounia Kamal

PURPOSE

Design and develop an epoxy resin-based cylindrical phantom to simulate cancer treatment conditions in high dose rate (HDR) brachytherapy and evaluate the spatial dose distribution around a ¹⁹²Ir source using an Sulfamic Acid/EPR system.

METHODS AND MATERIALS

A cylindrical phantom was fabricated from epoxy resin, allowing the precise insertion of a ¹⁹²Ir HDR brachytherapy source and multiple sulfamic acid dosimeters at predefined positions. The dosimetric system used in this study combined sulfamic acid detectors with EPR readout to quantify absorbed doses. Dosimeters were irradiated with doses ranging from 1 to 8 Gy, and the EPR signal intensities were measured to construct a calibration curve. Several dosimeters were then strategically positioned at various distances from the source to experimentally determine the dose distribution within the phantom.

RESULTS

The EPR dosimetry system showed a linear dose-response relationship within the 1-8 Gy range. The absorbed dose values at different locations were derived from the established calibration curve. A steep dose gradient was observed near the ¹⁹²Ir source, in agreement with theoretical expectations for HDR brachytherapy. The overall uncertainty in the dose evaluation process was estimated to be approximately 8% (k = 2).

CONCLUSIONS

This study demonstrates that the EPR/sulfamic acid dosimetry system provides a reliable and accurate method for dose evaluation in HDR brachytherapy. The developed epoxy resin phantom offers a practical and reproducible platform for experimental dose verification and quality assurance in brachytherapy treatments.

目的：设计和研制一种基于环氧树脂的圆柱形模体，用于模拟高剂量率（HDR）近距离治疗中的癌症治疗条件，并使用氨基磺酸/EPR系统评估192Ir源周围的空间剂量分布。方法和材料：用环氧树脂制成圆柱形模体，允许在预定位置精确插入192Ir HDR近距离治疗源和多个氨基甲酸剂量计。本研究中使用的剂量学系统结合了氨基磺酸检测器和EPR读数来量化吸收剂量。以1 ~ 8gy的剂量照射剂量计，测量EPR信号强度，建立校准曲线。然后将几个剂量计策略性地放置在离辐射源不同距离的位置，以实验方式确定模体内的剂量分布。结果：EPR剂量测定系统在1 ~ 8 Gy范围内呈线性剂量-效应关系。根据所建立的校准曲线得到不同位置的吸收剂量值。在192Ir源附近观察到一个陡峭的剂量梯度，与HDR近距离治疗的理论预期一致。剂量评估过程的总体不确定度估计约为8% （k = 2）。结论：EPR/氨基磺酸剂量测定系统为HDR近距离放射治疗的剂量评估提供了可靠、准确的方法。所开发的环氧树脂模体为近距离治疗的实验剂量验证和质量保证提供了一个实用和可复制的平台。

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引用次数: 0

MRI-based predictors of treatment failure in intermediate-risk prostate cancer treated with high-dose-rate brachytherapy as monotherapy 高剂量率近距离放射治疗作为单药治疗的中危前列腺癌治疗失败的mri预测因子

IF 1.8 4区医学 Q4 ONCOLOGY

Brachytherapy

Pub Date : 2026-01-01 Epub Date: 2025-11-19 DOI: 10.1016/j.brachy.2025.10.012

Jacob F. Oyeniyi , Joseph S. Lee , Chen Shen , Bailey A. Loving , Sirisha R. Nandalur , Andrew B. Thompson , Kiran R. Nandalur , Zachary A. Seymour , Evelyn L. Sebastian , Amy Limbacher , Alvaro Martinez , Daniel J. Krauss

OBJECTIVE

To identify MRI features associated with treatment failure in intermediate-risk prostate cancer patients treated with HDR brachytherapy monotherapy.

METHODS

We analyzed 115 men with intermediate-risk prostate cancer who underwent definitive HDR brachytherapy as monotherapy and had pretreatment MRI within 6 months. MRI features assessed included lesion size, focality, location, capsular contact (yes vs. no, with no gross extracapsular extension), length of capsular contact, and PIRADS score. Univariable and multivariate logistic regression analyses were performed to identify MRI features associated with treatment failure, defined as biochemical recurrence and/or local recurrence.

RESULTS

The median age was 64 years, and median pretreatment PSA 5.95 ng/mL; 49 patients had favorable and 66 had unfavorable intermediate-risk disease. At 47 months median follow-up, 19 patients (16.5%) experienced treatment failure. MRI features associated with treatment failure on UVA included lesion size (OR: 3.9, CI: 1.8–8.8, p < 0.001), multifocality (OR: 2.9, CI: 1.0–7.9, p = 0.043), capsular contact (OR: 64.3, CI: 8.1–510.0, p < 0.001), capsular contact length ≥1 cm (OR: 5.0, CI: 1.6–15.7, p = 0.006), and PIRADS 5 (OR: 16.7, CI: 2.7–324.8, p = 0.011). On MVA, only capsular contact remained significant (OR: 57.2, CI: 9.5–106.2, p < 0.001). In patients with capsular contact (n = 39), ADT significantly reduced treatment failure (OR: 0.101, CI: 0.002–0.912, p = 0.023).

CONCLUSION

Capsular contact on MRI is a strong independent predictor of treatment failure in intermediate-risk prostate cancer patients undergoing HDR brachytherapy as monotherapy. The addition of ADT significantly decreased the odds of treatment failure in these patients. These findings highlight the value of MRI-based risk stratification and suggest that treatment intensification options such as ADT could be considered to optimize treatment outcomes.

目的：探讨HDR近距离单药治疗中危前列腺癌患者治疗失败的MRI特征。方法：我们分析了115例中危前列腺癌患者，他们在6个月内接受了明确的HDR近距离治疗作为单药治疗，并进行了MRI预处理。评估的MRI特征包括病变大小、病灶性、位置、囊膜接触（有或没有，无大体囊外延伸）、囊膜接触长度和PIRADS评分。进行单变量和多变量logistic回归分析，以确定与治疗失败相关的MRI特征，定义为生化复发和/或局部复发。结果：中位年龄64岁，中位预处理PSA 5.95 ng/mL；有利中危49例，不利中危66例。在47个月的中位随访中，19例患者（16.5%）出现治疗失败。与UVA治疗失败相关的MRI特征包括病灶大小（OR: 3.9, CI: 1.8-8.8, p ）。结论：MRI上囊膜接触是接受HDR近距离放疗作为单药治疗的中危险前列腺癌患者治疗失败的一个强有力的独立预测因子。ADT的加入显著降低了这些患者治疗失败的几率。这些发现强调了基于mri的风险分层的价值，并建议可以考虑治疗强化方案，如ADT，以优化治疗结果。

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引用次数: 0

Salvage brachytherapy for local recurrence of prostate cancer. Evaluation of technique and dose fractionation, impact of early diagnosis, and its effect on survival. A multicenter retrospective observational study: RESPRO 前列腺癌局部复发的抢救性近距离放疗。技术和剂量分级的评价，早期诊断的影响及其对生存的影响。多中心回顾性观察性研究：RESPRO。

IF 1.8 4区医学 Q4 ONCOLOGY

Brachytherapy

Pub Date : 2026-01-01 Epub Date: 2025-11-21 DOI: 10.1016/j.brachy.2025.09.014

Patricia Willisch , Elena Villafranca , Susana Roldan Ortega , Silvia Rodriguez Villalba , Alai Goñi , Juan Adrian Camus , Luis Sopeña Sanz , Ana Alonso García , Teresa Muñoz Miguelañez , Saul Lopez-Soliño , Beatriz Vázquez-Barreiro , David Büchser

PURPOSE

To evaluate oncologic outcomes, prognostic factors, and toxicity associated with salvage brachytherapy in locally recurrent prostate cancer after radiotherapy and assess the role of next-generation imaging in early detection.

METHODS

A retrospective, multicenter cohort study was conducted including 188 patients treated with salvage HDR or LDR brachytherapy, with or without androgen deprivation therapy (ADT), across 10 Spanish centers. Primary endpoints were biochemical relapse-free survival (bRFS), clinical relapse-free survival (CRFS), and overall survival (OS). Survival probabilities were estimated using the Kaplan-Meier method, and predictive factors assessed using Cox proportional hazards models.

RESULTS

With a median follow-up of 64.6 months, 5- and 10-year bRFS were 64.9% and 61.7%, and CRFS were 72.3% and 68.1%, respectively. OS at 5 and 10 years was 97.9% and 93.6%. Time to PSA nadir and lower nadir values were associated with improved bRFS and CRFS. Gleason score >7 and higher PSA at recurrence predicted worse outcomes. Next-generation imaging enhanced early detection. BED >216 Gy improved control but raised urinary toxicity. Grade 3 acute and late urinary toxicity rates were 2.8% and 3.1%, respectively.

CONCLUSIONS

Salvage brachytherapy is an effective option for locally recurrent prostate cancer. PSA dynamics and advanced imaging improve patient selection. BED optimization remains critical.

目的：评估局部复发前列腺癌放疗后补救性近距离放疗的肿瘤预后、预后因素和毒性，并评估新一代影像学在早期发现中的作用。方法：一项回顾性、多中心队列研究，包括188名接受补救性HDR或LDR近距离放疗，伴或不伴雄激素剥夺治疗（ADT）的患者，来自西班牙10个中心。主要终点为生化无复发生存期（bRFS）、临床无复发生存期（CRFS）和总生存期（OS）。使用Kaplan-Meier法估计生存概率，使用Cox比例风险模型评估预测因素。结果：中位随访64.6个月，5年和10年bRFS分别为64.9%和61.7%，CRFS分别为72.3%和68.1%。5年和10年生存率分别为97.9%和93.6%。到达PSA最低点和较低最低点的时间与改善的bRFS和CRFS相关。Gleason评分为bb70，复发时PSA升高预示预后较差。下一代成像增强了早期检测。BED >216 Gy改善了控制，但增加了尿毒性。3级急性和晚期尿毒性发生率分别为2.8%和3.1%。结论：挽救性近距离放射治疗是局部复发前列腺癌的有效选择。PSA动态和先进的成像技术改善了患者的选择。BED优化仍然至关重要。

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引用次数: 0

Development of a dosimetric phantom using OSLDs or TLD-100 for external audits of high-dose-rate 192Ir brachytherapy sources: Preliminary results 使用osld或TLD-100进行高剂量率192Ir近距离治疗源外部审计的剂量学假体的开发：初步结果。

IF 1.8 4区医学 Q4 ONCOLOGY

Brachytherapy

Pub Date : 2026-01-01 Epub Date: 2025-11-21 DOI: 10.1016/j.brachy.2025.09.013

Carla L․ Mota , Carlos Eduardo de Almeida , Vanessa M․ Castro , Aneli O․ da Silva , Yvone Maria M․ Hornos , Maria de Fátima A․ Magon , Daniel Villani

PURPOSE

Calibration and quality control are fundamental to ensure that an accurate dose is delivered to a tumor, by HDR 192Ir radioactive sources in brachytherapy treatments. Consequently, it is essential for each radiation oncology center to implement a quality assurance program that includes an external audit. A cost-effective strategy, to meet the biannual requirements of licensing authorities, is the use of a well-established postal audit system employing phantoms and passive detectors.

METHODS

The primary aim of this study was to design and construct a PMMA phantom measuring 14 × 14 × 14 cm³, featuring a rectangular insert with 1 slot on each side capable of accommodating either a single Al₂O₃:C OSLD or 4 LiF-100 TLD chips, along with a central channel for positioning the 192Ir source. The source is aligned perpendicular to the geometric center of the detectors to optimize dose measurements while minimizing geometric effects. Both the phantom and detector modalities were tested using a Nucletron HDR 192Ir source and its TPS. Correction factors were determined to increase measurement accuracy.

RESULTS

The developed system demonstrates sufficient accuracy to meet the ±5% acceptance criterion for remote audits of HDR 192Ir brachytherapy sources.

CONCLUSIONS

Following successful testing, it is now intended to cover the 106 brachytherapy centers in Brazil, with the potential for expansion to additional centers throughout Latin America. The feasibility of using both detector types has been positively confirmed, offering flexibility and robustness to the audit system.

目的：校准和质量控制是确保近距离放射治疗中HDR 192Ir放射源向肿瘤提供准确剂量的基础。因此，每个放射肿瘤学中心都必须实施包括外部审计在内的质量保证计划。为了满足许可证当局一年两次的要求，一项具有成本效益的战略是使用一个完善的邮政审计系统，采用幽灵和被动探测器。方法：本研究的主要目的是设计和构建一个尺寸为14 × 14 × 14 cm³的PMMA模体，其特征是一个矩形插入，每侧有一个插槽，能够容纳单个Al₂O₃：C OSLD或4个liff -100 TLD芯片，以及一个用于定位192Ir源的中心通道。源垂直于探测器的几何中心排列，以优化剂量测量，同时最小化几何效应。使用核子HDR 192Ir源及其TPS测试了幻影和探测器模式。确定校正因子以提高测量精度。结果：所开发的系统具有足够的准确度，可满足HDR 192Ir近距离治疗源远程审计±5%的可接受标准。结论：在测试成功后，现在计划覆盖巴西的106个近距离放射治疗中心，并有可能扩展到整个拉丁美洲的其他中心。使用这两种检测器的可行性已得到肯定，为审计系统提供了灵活性和稳健性。

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引用次数: 0

Impact of locoregional treatment intensification in stampede high-risk M0 prostate cancer patients 局部强化治疗对踩踏高危M0前列腺癌患者的影响。

IF 1.8 4区医学 Q4 ONCOLOGY

Brachytherapy

Pub Date : 2026-01-01 Epub Date: 2025-10-14 DOI: 10.1016/j.brachy.2025.09.006

Jackson Howell, Jonathan Tward

INTRODUCTION

This study evaluates the efficacy of locoregional treatment intensification with combined modality therapy (CMT) for STAMPEDE high-risk (SHR) nonmetastatic (M0) prostate cancer. We compare metastasis-free survival (MFS) and overall survival (OS) between external beam radiation therapy (EBRT) with androgen deprivation therapy (ADT), CMT with a brachytherapy boost, and up-front surgery.

MATERIAL AND METHODS

A retrospective cohort of 217 SHR patients from our institutional database was stratified by treatment modality: EBRT + ADT (n = 56), CMT (n = 61), and surgery (n = 100). Median ADT duration was 24 months for the EBRT + ADT group and 6 months for the CMT group. Primary outcomes were MFS and OS, analyzed using Cox proportional hazards regression and Fine-Gray competing risks models, adjusted for PSA, age, and Gleason group.

RESULTS

CMT significantly improved adjusted MFS compared to EBRT + ADT (HR 0.41; p = 0.004). In contrast, up-front surgery did not significantly improve MFS over EBRT + ADT (HR 0.84; p = 0.471). Adjusted OS was also superior with CMT compared to EBRT + ADT (HR 1.98; p = 0.025). On subgroup analysis, the MFS benefit of CMT persisted for N0 patients but not for N1 patients. A key limitation is the retrospective, nonrandomized nature of the data.

DISCUSSION AND CONCLUSIONS

Locoregional treatment intensification with CMT and de-intensified ADT offers significant oncologic benefits in men with SHR M0 prostate cancer, particularly in N0 patients. These findings support further investigation into combining brachytherapy and systemic therapy with de-intensified ADT in prospective trials.

本研究评估了局部区域强化治疗联合模式治疗（CMT）对STAMPEDE高危（SHR）非转移性（M0）前列腺癌的疗效。我们比较了外束放射治疗（EBRT）联合雄激素剥夺治疗（ADT）、CMT联合近距离治疗和前期手术的无转移生存期（MFS）和总生存期（OS）。材料和方法：来自我们机构数据库的217例SHR患者的回顾性队列按治疗方式分层：EBRT + ADT (n = 56),CMT （n = 61）和手术（n = 100）。EBRT + ADT组的中位ADT持续时间为24个月，CMT组为6个月。主要结果是MFS和OS，使用Cox比例风险回归和Fine-Gray竞争风险模型进行分析，并根据PSA、年龄和Gleason组进行调整。结果：与EBRT + ADT相比，CMT显著改善了调整后的MFS （HR 0.41; p = 0.004）。相比之下，与EBRT + ADT相比，前期手术并没有显著改善MFS （HR 0.84; p = 0.471）。与EBRT + ADT相比，CMT的调整OS也优于EBRT （HR 1.98; p = 0.025）。在亚组分析中，CMT的MFS益处在N0例患者中持续存在，而在N1例患者中则没有。一个关键的限制是数据的回顾性和非随机性质。讨论和结论：局部强化CMT治疗和去强化ADT治疗对SHR M0前列腺癌患者，特别是N0患者有显著的肿瘤学益处。这些发现支持在前瞻性试验中进一步研究将近距离治疗和全身治疗与去强化ADT相结合。

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引用次数: 0

Integration of single-click, AI-based brachytherapy auto-planning for cervical cancer within a treatment planning system 将基于人工智能的宫颈癌近距离治疗自动计划整合到一个治疗计划系统中。

IF 1.8 4区医学 Q4 ONCOLOGY

Brachytherapy

Pub Date : 2026-01-01 Epub Date: 2025-10-22 DOI: 10.1016/j.brachy.2025.08.004

Ryan Truong , Lance C. Moore , Aranyo Mitra , Karoline Kallis , Kelly Kisling , Nuno Vasconcelos , Sandra M. Meyers

Purpose

Previous work developed an automated cervical brachytherapy treatment planning pipeline consisting of a U-Net dose prediction model and dwell time optimizer. While this method can produce clinically acceptable plans, it relies on time-consuming, manual export and import of DICOM data. This study proposes to increase efficiency by combining scripts into an all-in-one tool that can be used directly within the BrachyVision treatment planning system, producing automated plans in a single click.

Materials and Methods

We developed an AI-based planning tool through four main tasks; data retrieval, model inference, dwell time optimization, and auto-plan import. First, a C# plug-in interacts with the currently open patient in BrachyVision. Next, for data retrieval, model inference, and dwell time optimization, a Python executable operates on the data before the optimized dwell times are copied back into the open plan in BrachyVision. The script was tested on 28 brachytherapy plans spanning 7 applicator types, and auto-plans were compared to clinical plans using mean absolute error (MAE) in voxel-based 3D dose and dwell times.

Results

The average (± standard deviation) MAE in 3D dose and dwell times were 3.8 ± 0.7% (normalized to the prescribed dose) and 10.3 ± 7.4 s (2.1 ± 0.9% of the total plan dwell time), respectively. The average runtime of the script was 3.5 ± 1.2 minutes.

Conclusions

We developed a script that enables efficient, streamlined auto-planning directly within BrachyVision. After contouring and digitization are performed, the script can be run to produce high-quality, customized plans with a single button-click in a few minutes.

目的：先前的工作开发了一个由U-Net剂量预测模型和停留时间优化器组成的自动化宫颈近距离治疗计划管道。虽然这种方法可以产生临床可接受的计划，但它依赖于耗时的手动导出和导入DICOM数据。本研究提出通过将脚本组合成一个可直接在BrachyVision治疗计划系统中使用的一体化工具来提高效率，只需点击一次即可生成自动化计划。材料和方法：我们通过四个主要任务开发了一个基于人工智能的规划工具；数据检索、模型推断、停留时间优化和自动计划导入。首先，c#插件与BrachyVision中当前开放的患者进行交互。接下来，对于数据检索、模型推断和停留时间优化，Python可执行文件在优化的停留时间被复制回BrachyVision中的开放计划之前对数据进行操作。该脚本在28种近距离治疗计划中进行了测试，涵盖7种涂抹器类型，并使用基于体素的3D剂量和停留时间的平均绝对误差（MAE）将自动计划与临床计划进行了比较。结果：三维剂量和停留时间的平均（±标准差）MAE分别为3.8 ± 0.7%（归一化至规定剂量）和10.3 ± 7.4 s（2.1 ± 0.9%）。该脚本的平均运行时间为3.5 ± 1.2分钟。结论：我们开发了一个脚本，可以直接在BrachyVision中实现高效、流线型的自动规划。轮廓和数字化完成后，脚本可以在几分钟内运行，只需单击一个按钮，就可以生成高质量的定制计划。

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引用次数: 0