PURPOSE: STereotactic Arrhythmia Radioablation (STAR) showed promising results in patients with refractory ventricular tachycardia. However, clinical data are scarce and heterogeneous. The STOPSTORM.eu consortium was established to investigate and harmonize STAR in Europe. The primary goal of this benchmark study was to investigate current treatment planning practice within the STOPSTORM project as a baseline for future harmonization. METHODS AND MATERIALS: Planning target volumes (PTVs) overlapping extracardiac organs-at-risk and/or cardiac substructures were generated for 3 STAR cases. Participating centers were asked to create single-fraction treatment plans with 25 Gy dose prescriptions based on in-house clinical practice. All treatment plans were reviewed by an expert panel and quantitative crowd knowledge-based analysis was performed with independent software using descriptive statistics for International Commission on Radiation Units and Measurements report 91 relevant parameters and crowd dose-volume histograms. Thereafter, treatment planning consensus statements were established using a dual-stage voting process. RESULTS: Twenty centers submitted 67 treatment plans for this study. In most plans (75%) intensity modulated arc therapy with 6 MV flattening filter free beams was used. Dose prescription was mainly based on PTV D95% (49%) or D96%-100% (19%). Many participants preferred to spare close extracardiac organs-at-risk (75%) and cardiac substructures (50%) by PTV coverage reduction. PTV D0.035cm3 ranged from 25.5 to 34.6 Gy, demonstrating a large variety of dose inhomogeneity. Estimated treatment times without motion compensation or setup ranged from 2 to 80 minutes. For the consensus statements, a strong agreement was reached for beam technique planning, dose calculation, prescription methods, and trade-offs between target and extracardiac critical structures. No agreement was reached on cardiac substructure dose limitations and on desired dose inhomogeneity in the target. CONCLUSIONS: This STOPSTORM multicenter treatment planning benchmark study not only showed strong agreement on several aspects of STAR treatment planning, but also revealed disagreement on others. To standardize and harmonize STAR in the future, consensus statements were established; however, clinical data are urgently needed for actionable guidelines for treatment planning.
- MeSH
- benchmarking * MeSH
- celková dávka radioterapie MeSH
- komorová tachykardie chirurgie radioterapie MeSH
- konsensus * MeSH
- kritické orgány * účinky záření MeSH
- lidé MeSH
- plánování radioterapie pomocí počítače * normy metody MeSH
- radiochirurgie * normy metody MeSH
- radioterapie s modulovanou intenzitou metody normy MeSH
- srdce účinky záření MeSH
- srdeční arytmie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
- Geografické názvy
- Evropa MeSH
Akcelerovaná parciální iradiace prsu (APBI) je ověřená metoda ozáření pacientek s časným karcinomem prsu, které splňují indikační kritéria. Perioperační zavádění brachyterapeutických vodičů zkracuje celkovou dobu léčby z několika týdnů na přibližně 14 dní a umožňuje zavádění vodičů pod přímou vizuální kontrolou ihned po odstranění nádorového ložiska. Díky screeningovému programu a časné diagnostice pacientek stále roste počet pacientek vhodných pro tuto léčbu.
Accelerated partial breast irradiation (APBI) is a well-established technique for irradiating patients with early-stage breast cancer who meet the indication criteria. The perioperative insertion of brachytherapy catheters reduces the overall treatment time from several weeks to approximately 14 days and allows for catheter placement under direct visual control immediately after tumor removal. Thanks to screening programs and early-stage diagnosis, the number of patients eligible for this treatment continues to rise.
- MeSH
- brachyterapie * metody MeSH
- časná diagnóza MeSH
- lidé MeSH
- nádory prsu * chirurgie radioterapie MeSH
- perioperační péče metody MeSH
- plánování radioterapie pomocí počítače metody MeSH
- pooperační péče metody MeSH
- radioterapie metody škodlivé účinky MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- přehledy MeSH
Brachyterapie s vysokým dávkovým příkonem (high dose rate brachytherapy, HDR BRT) je dnes prováděna výhradně automatickými afterloadingovými ozařovači. Nejčastějšími jsou aplikace intrakavitární a intersticiální, případně jejich kombinace. Důležitým aspektem plánování intersticiální brachyterapie je spolupráce lékaře s fyzikem již ve fázi zavádění aplikátorů. Úprava geometrie zavedených aplikátorů v pozdější fázi již často není realizovatelná. Pro výpočet ozařovacích plánů brachyterapie lze využít řadu zobrazovacích modalit. V článku jsou shrnuty fyzikální parametry hodnocení kvality ozařovacích plánů a cíle jejich optimalizace.
High dose rate brachytherapy is realized solely by automatic afterloading irradiators nowadays. The most common are intracavitary and interstitial applications. Cooperation between a physician and a physicist before insertion of applicators is a very important aspect. Changes of applicators' geometry are usually not possible afterwards. A range of imaging modalities can be used for brachytherapy planning. A physical parameters useful for quality assessment and optimization of the plans are presented in this article.
- Klíčová slova
- afterloading,
- MeSH
- brachyterapie * metody přístrojové vybavení MeSH
- celková dávka radioterapie MeSH
- fyzikální jevy * MeSH
- lidé MeSH
- nádory diagnostické zobrazování radioterapie MeSH
- plánování radioterapie pomocí počítače metody přístrojové vybavení MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
Intersticiální high-dose rate brachyterapie (HDR BRT) představuje slibnou metodu léčby časného karcinomu penisu, která v mnoha případech slouží jako alternativa k primární chirurgické léčbě. Tato technika umožňuje zachování celistvosti penisu až u 80 % pacientů, kteří by jinak museli podstoupit radikální operaci. Výsledkem je nejen lepší kvalita života pacientů, ale také výrazně nižší výskyt psychických problémů spojených s léčbou. Důležitým přínosem je rovněž možnost zachování sexuálních funkcí na úrovni srovnatelné s obdobím před zahájením léčby.
Interstitial high-dose rate brachytherapy (HDR BRT) is a promising treatment method for early-stage penile cancer, which in many cases serves as an alternative to primary surgical treatment. This technique allows for the preservation of the penis integrity in up to 80% of patients who would otherwise require radical surgery. As a result, patients experience not only a better quality of life but also significantly fewer post-treatment psychological issues. An important benefit is also the ability to maintain sexual function at a level comparable to that before the treatment.
BACKGROUND/PURPOSE: High doses to healthy cardiac substructures (CS) in stereotactic arrhythmia radioablation (STAR) raise concerns regarding potential treatment-induced cardio-toxicity. However, CS contours are not routinely created, hindering the understanding of the CS dose-effect relationships. To address this issue, the alignment of CS contouring was initiated within the STOPSTORM consortium. In this study, we developed and evaluated auto-contouring models trained to delineate CS and major vessels in ventricular tachycardia (VT) patients. METHODS: Eight centres provided standard treatment planning computed tomography (CT) and/or contrast-enhanced CT datasets of 55 VT patients, each including 16 CS. Auto-contouring models were trained to contour either large structures or small structures. Dice Similarity Coefficient (DSC), 95 % Hausdorff distance (HD95) and volume ratio (VR) were used to evaluate model performance versus inter-observer variation (IOV) on seven VT patient test cases. Significant differences were tested using the Mann-Whitney U test. RESULTS: The performance on the four chambers and the major vessels (median DSC: 0.88; HD95: 5.8-19.4 mm; VR: 1.09) was similar to the IOV (median DSC: 0.89; HD95: 4.8-14.0 mm; VR: 1.20). For the valves, model performance (median DSC: 0.37; HD95: 11.6 mm; VR: 1.63) was similar to the IOV (median DSC: 0.41; HD95: 12.4 mm; VR: 3.42), but slightly worse for the coronary arteries (median DSC: 0.33 vs 0.42; HD95: 24.4 mm vs 16.9 mm; VR: 1.93 vs 3.30). The IOV for these small structures remains large despite using contouring guidelines. CONCLUSION: CS auto-contouring models trained on VT patient data perform similarly to IOV. This allows for time-efficient evaluation of CS as possible organs-at-risk.
- MeSH
- komorová tachykardie * MeSH
- kritické orgány účinky záření MeSH
- lidé středního věku MeSH
- lidé MeSH
- plánování radioterapie pomocí počítače metody MeSH
- počítačová rentgenová tomografie * MeSH
- radiochirurgie * metody MeSH
- senioři MeSH
- srdce účinky záření MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
PURPOSE: Recent papers suggested a correlation between the risk of distant metastasis (DM) and dose outside the PTV, though conclusions in different publications conflicted. This study resolves these conflicts and provides a compelling explanation of prognostic factors. MATERIALS AND METHODS: A dataset of 478 NSCLC patients treated with SBRT (IMRT or VMAT) was analyzed. We developed a deep learning model for DM prediction and explainable AI was used to identify the most significant prognostic factors. Subsequently, the prognostic power of the extracted features and clinical details were analyzed using conventional statistical methods. RESULTS: Treatment technique, tumor features, and dosiomic features in a 3 cm wide ring around the PTV (PTV3cm) were identified as the strongest predictors of DM. The Hazard Ratio (HR) for Dmean,PTV3cm was significantly above 1 (p < 0.001). There was no significance of the PTV3cm dose after treatment technique stratification. However, the dose in PTV3cm was found to be a highly significant DM predictor (HR > 1, p = 0.004) when analyzing only VMAT patients with small and spherical tumors (i.e., sphericity > 0.5). CONCLUSIONS: The main reason for conflicting conclusions in previous papers was inconsistent datasets and insufficient consideration of confounding variables. No causal correlation between the risk of DM and dose outside the PTV was found. However, the mean dose to PTV3cm can be a significant predictor of DM in small spherical targets treated with VMAT, which might clinically imply considering larger PTV margins for smaller, more spherical tumors (e.g., if IGTV > 2 cm, then margin ≤ 7 mm, else margin > 7 mm).
- MeSH
- celková dávka radioterapie * MeSH
- deep learning * MeSH
- lidé středního věku MeSH
- lidé MeSH
- metastázy nádorů MeSH
- nádory plic * patologie radioterapie MeSH
- nemalobuněčný karcinom plic * radioterapie patologie MeSH
- plánování radioterapie pomocí počítače metody MeSH
- prognóza MeSH
- radiochirurgie * metody MeSH
- radioterapie s modulovanou intenzitou metody MeSH
- senioři MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Artificial intelligence (AI) has made a tremendous impact in the space of healthcare, and proton therapy is not an exception. Proton therapy has witnessed growing popularity in oncology over recent decades, and researchers are increasingly looking to develop AI and machine learning tools to aid in various steps of the treatment planning and delivery processes. This review delves into the emergent role of AI in proton therapy, evaluating its development, advantages, intended clinical contexts, and areas of application. Through the analysis of 76 studies, we aim to underscore the importance of AI applications in advancing proton therapy and to highlight their prospective influence on clinical practices.
- MeSH
- lidé MeSH
- nádory * radioterapie terapie MeSH
- plánování radioterapie pomocí počítače metody MeSH
- protonová terapie * metody MeSH
- strojové učení MeSH
- umělá inteligence * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
BACKGROUND: Ultra high dose rate (UHDR) radiotherapy using ridge filter is a new treatment modality known as conformal FLASH that, when optimized for dose, dose rate (DR), and linear energy transfer (LET), has the potential to reduce damage to healthy tissue without sacrificing tumor killing efficacy via the FLASH effect. PURPOSE: Clinical implementation of conformal FLASH proton therapy has been limited by quality assurance (QA) challenges, which include direct measurement of UHDR and LET. Voxel DR distributions and LET spectra at planning target margins are paramount to the DR/LET-related sparing of organs at risk. We hereby present a methodology to achieve experimental validation of these parameters. METHODS: Dose, DR, and LET were measured for a conformal FLASH treatment plan involving a 250-MeV proton beam and a 3D-printed ridge filter designed to uniformly irradiate a spherical target. We measured dose and DR simultaneously using a 4D multi-layer strip ionization chamber (MLSIC) under UHDR conditions. Additionally, we developed an "under-sample and recover (USRe)" technique for a high-resolution pixelated semiconductor detector, Timepix3, to avoid event pile-up and to correct measured LET at high-proton-flux locations without undesirable beam modifications. Confirmation of these measurements was done using a MatriXX PT detector and by Monte Carlo (MC) simulations. RESULTS: MC conformal FLASH computed doses had gamma passing rates of >95% (3 mm/3% criteria) when compared to MatriXX PT and MLSIC data. At the lateral margin, DR showed average agreement values within 0.3% of simulation at 100 Gy/s and fluctuations ∼10% at 15 Gy/s. LET spectra in the proximal, lateral, and distal margins had Bhattacharyya distances of <1.3%. CONCLUSION: Our measurements with the MLSIC and Timepix3 detectors shown that the DR distributions for UHDR scenarios and LET spectra using USRe are in agreement with simulations. These results demonstrate that the methodology presented here can be used effectively for the experimental validation and QA of FLASH treatment plans.
PURPOSE: The time structures of proton spot delivery in proton pencil beam scanning (PBS) radiation therapy are essential in many clinical applications. This study aims to characterize the time structures of proton PBS delivered by both synchrotron and synchrocyclotron accelerators using a non-invasive technique based on scattered particle tracking. METHODS: A pixelated semiconductor detector, AdvaPIX-Timepix3, with a temporal resolution of 1.56 ns, was employed to measure time of arrival of secondary particles generated by a proton beam. The detector was placed laterally to the high-flux area of the beam in order to allow for single particle detection and not interfere with the treatment. The detector recorded counts of radiation events, their deposited energy and the timestamp associated with the single events. Individual recorded events and their temporal characteristics were used to analyze beam time structures, including energy layer switch time, magnet switch time, spot switch time, and the scanning speeds in the x and y directions. All the measurements were repeated 30 times on three dates, reducing statistical uncertainty. RESULTS: The uncertainty of the measured energy layer switch times, magnet switch time, and the spot switch time were all within 1% of average values. The scanning speeds uncertainties were within 1.5% and are more precise than previously reported results. The measurements also revealed continuous sub-milliseconds proton spills at a low dose rate for the synchrotron accelerator and radiofrequency pulses at 7 μs and 1 ms repetition time for the synchrocyclotron accelerator. CONCLUSION: The AdvaPIX-Timepix3 detector can be used to directly measure and monitor time structures on microseconds scale of the PBS proton beam delivery. This method yielded results with high precision and is completely independent of the machine log files.
- MeSH
- časové faktory MeSH
- částice - urychlovače * přístrojové vybavení MeSH
- celková dávka radioterapie * MeSH
- lidé MeSH
- nádory radioterapie MeSH
- plánování radioterapie pomocí počítače * metody MeSH
- polovodiče * MeSH
- protonová terapie * přístrojové vybavení MeSH
- protony MeSH
- synchrotrony přístrojové vybavení MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Objective.This study aims to assess the composition of scattered particles generated in proton therapy for tumors situated proximal to some titanium (Ti) dental implants. The investigation involves decomposing the mixed field and recording Linear Energy Transfer (LET) spectra to quantify the influence of metallic dental inserts located behind the tumor.Approach.A therapeutic conformal proton beam was used to deliver the treatment plan to an anthropomorphic head phantom with two types of implants inserted in the target volume (made of Ti and plastic, respectively). The scattered radiation resulted during the irradiation was detected by a hybrid semiconductor pixel detector MiniPIX Timepix3 that was placed distal to the Spread-out Bragg peak. Visualization and field decomposition of stray radiation were generated using algorithms trained in particle recognition based on artificial intelligence neural networks (AI NN). Spectral sensitive aspects of the scattered radiation were collected using two angular positions of the detector relative to the beam direction: 0° and 60°.Results.Using AI NN, 3 classes of particles were identified: protons, electrons & photons, and ions & fast neutrons. Placing a Ti implant in the beam's path resulted in predominantly electrons and photons, contributing 52.2% of the total number of detected particles, whereas for plastic implants, the contribution was 65.4%. Scattered protons comprised 45.5% and 31.9% with and without metal inserts, respectively. The LET spectra were derived for each group of particles identified, with values ranging from 0.01 to 7.5 keVμm-1for Ti implants/plastic implants. The low-LET component was primarily composed of electrons and photons, while the high-LET component corresponded to protons and ions.Significance.This method, complemented by directional maps, holds the potential for evaluating and validating treatment plans involving stray radiation near organs at risk, offering precise discrimination of the mixed field, and enhancing in this way the LET calculation.
- MeSH
- fantomy radiodiagnostické * MeSH
- lidé MeSH
- lineární přenos energie * MeSH
- neuronové sítě MeSH
- plánování radioterapie pomocí počítače metody MeSH
- protézy a implantáty MeSH
- protonová terapie * metody přístrojové vybavení MeSH
- radiační rozptyl MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
