Search Results (225)

Adjuvant radiotherapy improves local cancer control and the overall survival of women with breast cancer. However, it is unclear what the ideal radiotherapy (RT) planning technique is for these patients. The aim was to perform a synopsis of the literature comparing RT techniques to treat early-stage left breast tumours. A PRISMA guideline was used on this systematic review and registered in PROSPERO (CRD420251168901). For all the investigations, the Open-field technique (OF) showed worse results for the Planning Target Volume (PTV), lung and heart. Field-in-Field stood out in low doses and mean doses in OARs. IMRT distinguished itself in Homogeneity Index. VMAT provides higher Conformity Index results and thus an advantage in high and mean doses of OARs. Hybrid-IMRT and Hybrid-VMAT combine the advantages of two techniques; however, few studies have included them in their research. There is not a clear “gold-standard” technique, and the results depend heavily on many factors which affect the quality of the plans and the priorities of the departments. However, OF is no longer recommended. An international framework should be developed to allow for a standardisation of the plans, improving inter-departmental comparisons. And each department should perform their own comparison between the techniques available to them. Full article

Background: Multimodal Deep learning has emerged as a crucial method for automated patient-specific quality assurance (PSQA) in radiotherapy research. Integrating image-based dose matrices with tabular plan complexity metrics enables more accurate prediction of quality indicators, including the Gamma Passing Rate (GPR) and dose difference (DD). However, modality imbalance remains a significant challenge, as tabular encoders often dominate training, suppressing image encoders and reducing model robustness. This issue becomes more pronounced under task heterogeneity, with GPR prediction relying more on tabular data, whereas dose difference prediction (DDP) depends heavily on image features. Methods: We propose BMMQA (Balanced Multi-modal Quality Assurance), a novel framework that achieves modality balance by adjusting modality-specific loss factors to control convergence dynamics. The framework introduces four key innovations: (1) task-specific fusion strategies (softmax-weighted attention for GPR regression and spatial cascading for DD prediction); (2) a balancing mechanism supported by Shapley values to quantify modality contributions; (3) a fast network forward mechanism for efficient computation of different modality combinations; and (4) a modality-contribution-based task weighting scheme for multi-task multimodal learning. A large-scale multimodal dataset comprising 1370 IMRT plans was curated in collaboration with Peking Union Medical College Hospital (PUMCH). Results: Experimental results demonstrate that, under the standard 2%/3 mm GPR criterion, BMMQA outperforms existing fusion baselines. Under the stricter 2%/2 mm criterion, it achieves a 15.7% reduction in mean absolute error (MAE). The framework also enhances robustness in critical failure cases (GPR < 90%) and achieves a peak SSIM of 0.964 in dose distribution prediction. Conclusions: Explicit modality balancing improves predictive accuracy and strengthens clinical trustworthiness by mitigating overreliance on a single modality. This work highlights the importance of addressing modality imbalance for building trustworthy and robust AI systems in PSQA and establishes a pioneering framework for multi-task multimodal learning. Full article

Background: The optimal treatment strategy for locally advanced unresectable pancreatic cancer (LAPC) is still investigated. Therefore, we evaluated the role of radiotherapy (RT) in the management of LAPC in the modern era. Methods: A systematic review was conducted following the Preferred Reporting Items for Systemic Review and Meta-Analyses guidelines. Eligible studies were about for LAPC treated with curative-intent modern RT techniques including intensity-modulated radiotherapy (IMRT), stereotactic body radiotherapy (SBRT), and particle beam therapy (PBT) until September 2024. Results: In total, 53 observational studies, encompassing 2548 patients (993 treated with IMRT, 998 with SBRT, and 557 with PBT), met the inclusion criteria. Concurrent chemoradiotherapy (CCRT) was implemented in 28 studies, including only 3 studies in the SBRT group. Elective nodal irradiation (ENI) was adopted in 22%. The pooled 2-year overall survival (OS) rate was 29% (95% confidence interval [CI], 25–34%) for all patients, with no significant differences among RT techniques: 28% (95% CI, 22–34%) for IMRT, 26% (95% CI, 19–34%) for SBRT, and 43% (95% CI, 28–57%) for PBT (p = 0.1121). The pooled rate of acute hematologic toxicity (HT) ≥ grade 3 was 17% (95% CI, 9–26%), with significant differences among RT techniques: 23% (95% CI, 9–40%) for IMRT, 4% (95% CI, 0–11%) for SBRT, and 20% (95% CI, 6–37%) for PBT (p = 0.0181). In addition, CCRT (p = 0.0084) and ENI (p = 0.0145) significantly increased the risk of acute HT. Gastrointestinal toxicities rarely occurred. Conclusions: This systematic review and meta-analysis showed similar efficacy among modern RT techniques for LAPC management. Since almost all studies have single-arm design, and chemotherapy regimens have changed over time, conclusions must be drawn with caution. The use of modern RT techniques is individually selected according to clinical practice and resource availability. Full article

Glioblastoma multiforme (GBM), the most aggressive primary brain tumor in adults, has a poor prognosis due to rapid recurrence and treatment resistance. This review examines the evolution of radiotherapy (RT) for GBM management, from whole-brain RT to modern techniques like intensity-modulated RT (IMRT) and volumetric modulated arc therapy (VMAT), guided by 2023 European Society for Radiotherapy and Oncology (ESTRO)-European Association of Neuro-Oncology (EANO) and 2025 American Society for Radiation Oncology (ASTRO) recommendations. The standard Stupp protocol (60 Gy/30 fractions with temozolomide [TMZ]) improves overall survival (OS) to 14.6 months, with greater benefits in O6-methylguanine-DNA methyltransferase (MGMT)-methylated tumors (21.7 months). Tumor Treating Fields (TTFields) extend median overall survival (mOS) to 31.6 months in MGMT-methylated patients and 20.9 months overall in supratentorial GBM (EF-14 trial). However, 80–90% of recurrences occur within 2 cm of the irradiated field due to tumor infiltration and radioresistance driven by epidermal growth factor receptor (EGFR) amplification, phosphatase and tensin homolog (PTEN) mutations, cyclin-dependent kinase inhibitor 2A/B (CDKN2A/B) deletions, tumor hypoxia, and tumor stem cells. Pseudoprogression, distinguished using Response Assessment in Neuro-Oncology (RANO) criteria and positron emission tomography (PET), complicates response evaluation. Targeted therapies (e.g., bevacizumab; PARP inhibitors) and immunotherapies (e.g., pembrolizumab; oncolytic viruses), alongside advanced imaging (multiparametric magnetic resonance imaging [MRI], amino acid PET), support personalized RT. Ongoing trials evaluating reirradiation, hypofractionation, stereotactic radiosurgery, neoadjuvant therapies, proton therapy (PT), boron neutron capture therapy (BNCT), and AI-driven planning aim to enhance efficacy for GBM IDH-wildtype, but phase III trials are needed to improve survival and quality of life. Full article

Background: To compare the costs of open retropubic radical prostatectomy (RRP), robotic-assisted radical prostatectomy (RALP), intensity-modulated radiation therapy (IMRT), low-dose brachytherapy (LDBT), stereotactic body radiotherapy (SBRT), cryotherapy (Cryo), and high-intensity focused ultrasound (HIFU) for low/intermediate-risk prostate cancer (PCa), from the healthcare system perspective. Methods: This retrospective, IRB-approved study compared the costs and charges of primary treatment options for localized PCa at Duke University Hospital between January 2018 and December 2019. We identified cases by querying the relevant disease, procedural, and charge codes from Duke Finance. Consecutive cases with NCCN high-risk disease, prior treatment, or missing institutional financial information were excluded. Costs were calculated from the point at which the treatment option was selected until the last treatment session (SBRT and IMRT) or hospital discharge (other modalities). All modalities except RRP were considered technology-intensive. Results: A total of 552 patients with a mean age of 65.0 years met the inclusion criteria. NCCN risk categories included 85 (13%) low, 218 (41%) favorable-intermediate, and 249 (46%) unfavorable-intermediate risk cases. RALP, RRP, Cryo, and HIFU were single-session treatments, whereas IMRT, SBRT, and LDBT were delivered over multiple sessions. IMRT and SBRT were the most expensive modalities, followed by RALP, HIFU, LDBT, Cryo, and RRP. The number of sessions (ρ = 0.55, p < 0.001) and being technology-intensive (ρ = 0.58, p < 0.001) were significantly correlated with treatment costs. Conclusions: In this cohort of PCa patients, treatment costs were highest for IMRT and SBRT, followed by RALP, HIFU, LDBT, Cryo, and RRP. The number of treatment sessions was a significant predictor of higher costs. Full article

Radiation-induced keratoconjunctivitis sicca (KCS) is a significant late complication in dogs receiving radiation therapy for intranasal tumors, particularly with hypofractionated intensity-modulated radiation therapy (IMRT). This retrospective case-control study was performed to identify anatomical and dosimetric risk factors for KCS in 15 canine patients treated with IMRT delivered in 4–6 weekly fractions of 8 Gy. Orbital structures were retrospectively contoured, and dose–volume metrics (D50) were calculated. Receiver operating characteristic (ROC) curve analysis and odds ratios were used to evaluate the associations between radiation dose and KCS development. Six dogs (33%) developed KCS within three months post-treatment. Statistically significant dose differences were observed between affected and unaffected eyes for the eyeball, cornea, and retina. ROC analyses identified dose thresholds predictive of KCS: 13.8 Gy (eyeball), 14.9 Gy (cornea), and 17.0 Gy (retina), with the retina showing the highest odds ratio (28.33). To ensure clinical relevance, KCS was diagnosed based on decreased tear production combined with corneal damage to ensure clinical relevance. This study proposes dose thresholds for ocular structures that may guide treatment planning and reduce the risk of KCS in canine patients undergoing IMRT. Further prospective studies are warranted to validate these thresholds and explore mitigation strategies for high-risk cases. Full article

Prostate cancer is one of the most prevalent malignancies in men, posing a significant public health challenge due to its high incidence and long-term treatment-related toxicities. Long-lived patients often experience prolonged side effects that can severely diminish their quality of life. Despite advancements in radiotherapy techniques like IMRT and VMAT, some patients still experience acute and late side effects. Current treatment protocols do not account for individual variability in normal-tissue radiosensitivity, highlighting the need for predictive tools and a personalised treatment approach. Genetic factors and molecular regulators like microRNAs (miRNAs) contribute to these variations by influencing DNA repair, inflammation, and apoptosis. This review explores potential biomarkers of radiotoxicity, focusing on immune-related factors such as IL-6 and TGF-β1, SNPs influencing radiosensitivity, miRNAs involved in radiation responses, and functional assays including the radiation-induced lymphocyte apoptosis (RILA) test. These approaches offer promising tools for identifying radiosensitive patients and enabling risk-adapted radiotherapy. Full article

Prostate cancer remains a major global health challenge, ranking as the second most common malignancy in men worldwide. Advances in diagnostic and therapeutic strategies have transformed its management, enhancing patient outcomes and quality of life. This review highlights recent breakthroughs in imaging, including multiparametric MRI and PSMA-PET, which have improved cancer detection and staging. Biomarker-based diagnostics, such as PHI and 4K Score, offer precise risk stratification, reducing unnecessary biopsies. Innovations in treatment, including robotic-assisted surgery, novel hormone therapies, immunotherapy, and PARP inhibitors, are redefining care for localized and advanced prostate cancer. Artificial intelligence (AI) and machine learning (ML) are emerging as powerful tools to optimize diagnostics, risk prediction, and treatment personalization. Additionally, advances in radiation therapy, such as IMRT and SBRT, provide targeted and effective options for high-risk patients. While these innovations have significantly improved survival and minimized overtreatment, challenges remain in optimizing therapy sequencing and addressing disparities in care. The integration of AI, theranostics, and gene-editing technologies holds immense promise for the future of prostate cancer management. Full article

An optimization framework that effectively balances dose–volume constraints and treatment objectives is required in intensity-modulated radiation therapy (IMRT) planning. In our previous work, we proposed a dynamical systems-based approach in which dose constraints, along with beam coefficients, are treated as state variables and dynamically evolve within a continuous-time system. This method improved the accuracy of the solution by dynamically adjusting the dose constraints, but it had a significant drawback. Specifically, because it is as an iterative process derived from discretization of a linear differential equation system using the additive Euler method, a lower-bound clipping procedure is required to prevent the state variables for both beam coefficients and dose constraints from taking negative values. This issue could prevent constrained optimization from functioning properly and undermine the feasibility of the treatment plan. To address this problem, we propose two types of multiplicative continuous-time dynamical system that inherently preserve the nonnegativity of the state variables. We theoretically prove that the initial value problem for these systems converges to a solution that satisfies the constraints of consistent IMRT planning. Furthermore, to ensure computational practicality, we derive discretized iterative schemes from the continuous-time systems and confirm that their iterations maintain nonnegativity. This framework eliminates the need for artificial clipping procedures and leads to the multiplicative variable dose-constraints method, which dynamically adjusts dose constraints during the optimization process. Finally, numerical experiments are conducted to support and illustrate the theoretical results, showing how the proposed method achieves high-precision IMRT planning while ensuring physically meaningful solutions. Full article

Background and Clinical Significance: Rectal angiosarcoma is an exceptionally rare and aggressive malignancy, comprising less than 1% of soft tissue sarcomas. This case highlights the diagnostic and therapeutic challenges posed by this disease, and the lack of established guidelines emphasizing the importance of a multidisciplinary approach. Case Presentation: A 41-year-old male firefighter, with a history of heavy smoking, presented with lower abdominal pain, rectal bleeding, and urgency. Imaging and biopsy confirmed rectal angiosarcoma, stage IIIB. The patient underwent IMRT/VMAT radiation therapy followed by laparoscopic rectal amputation with colostomy. No sign of recurrence or metastatic disease was present on follow-up imaging. Conclusions: This case underlines the importance of a personalized treatment strategy and multidisciplinary collaboration in rare malignancies. Early diagnosis and cooperation across specialties are critical for achieving the best possible outcomes. Full article

Background and Objectives: Brain radionecrosis is an under-recognized but potentially life-altering late complication of radiotherapy in patients with locally advanced nasopharyngeal cancer. Temporal lobe radionecrosis and high-dose exposure to the hippocampus are strongly associated with cognitive decline and radiation-induced dementia, negatively impacting patients’ long-term quality of life (QoL). This study aimed to evaluate and compare radiation dose distributions to critical brain structures across three radiotherapy techniques—3D conformal radiotherapy (3D-CRT), intensity-modulated radiotherapy (IMRT), and volumetric-modulated arc therapy (VMAT)—in order to assess potential neurocognitive risks and support hippocampal-sparing protocols. Materials and Methods: Ten patients previously treated with 3D-CRT were retrospectively replanned using IMRT and VMAT techniques on the Eclipse v13.3 (VARIAN) planning system. Bilateral hippocampi and temporal lobes were delineated as organs at risk (OARs) according to the RTOG atlas, and dosimetric parameters including D_max, D_mean, and D_min were recorded. V7.3 values were evaluated for hippocampal avoidance regions. Results: While IMRT and VMAT provided improved target volume coverage and reduced high-dose exposure to many standard OARs, both techniques were associated with increased D_mean and D_min to the hippocampus and temporal lobes compared to 3D-CRT. The highest D_max values to the temporal lobes were observed in 3D-CRT plans, indicating a potential risk of radionecrosis. VMAT plans showed hippocampal mean doses exceeding 10 Gy in some cases, with V7.3 > 40%, breaching established neurocognitive risk thresholds. Conclusions: These findings support the routine delineation of the hippocampus and temporal lobes as OARs in radiotherapy planning for nasopharyngeal cancer. The implementation of hippocampal-sparing strategies, particularly in IMRT and VMAT, is recommended to reduce the risk of radiation-induced cognitive toxicity and preserve long-term QoL in survivors. Full article

Purpose: This study aimed to compare long-term patient-reported outcomes in bowel and urinary domains between intensity-modulated radiotherapy (IMRT) and intensity-modulated proton therapy (IMPT) for localized prostate cancer. Methods and Materials: Patients with clinical T1–T2 prostate cancer receiving IMRT or IMPT at a tertiary cancer center from 2015–2018 were analyzed to determine the changes in the prospectively collected bowel function (BF), urinary irritative/obstructive symptoms (UO), and urinary incontinence (UI) domains of EPIC-26. The mean changes in EPIC-26 scores were evaluated from pretreatment to 24 months post-radiotherapy for each modality. A score change >50% of the baseline standard deviation was considered a clinically meaningful change. Results: A total of 82 patients treated with IMRT (52.2%) and 56 patients treated with IMPT (53.3%) completed the questionnaire at baseline and 24 months post-RT. There were no baseline differences in domain scores between treatment modalities. At 24 months post-radiotherapy, there was a significant and clinically meaningful decline in the BF mean score in the IMRT cohort (−4.52 (range −50, 29.17), p = 0.003), whereas the decline in BF score did not reach clinical relevance or significance (−1.88 (range −37.5, 50), p = 0.046) when accounting for the Bonferroni adjustment in the IMPT cohort. A higher proportion of patients treated with IMRT had a clinically relevant reduction in BF when compared with IMPT (47.37% vs. 25.93%, p = 0.017). The mean changes in the UI and UO scores of the IMRT and IMPT cohorts were neither statically significant nor clinically relevant. Conclusions: IMPT leads to a smaller decrease in BF than IMRT at 24 months post-RT, while there was no differential effect on UO and UI. Full article

Goal: This study evaluates the feasibility and outcome of a personalized MRI-based liver SBRT treatment planning platform with the SPION contrast agent Ferumoxytol^® (Sandoz Inc.; Princeton, NJ, USA) to maintain a superior real-time visualization of liver tumors and volumes of functional hepatic parenchyma for radiotherapy planning throughout multi-fractionated liver SBRT with online plan adaptations on an Elekta Unity 1.5 T MR-Linac (Elekta; Stockholm, Sweden). Materials and Methods: Patients underwent SPION-enhanced MRI on the Elekta Unity MR-Linac for improved tumor and functional hepatic parenchyma visualization. An automated contouring algorithm was applied for the delineation and subsequent guided avoidance of functional liver parenchyma volumes (FLVs) on the SPION-enhanced MR-Linac. Radiation dose constraints were adapted exclusively to FLV. Local control, toxicity, and survival were assessed with at least 6-month radiographic follow-up. Pre- and post-transplant outcomes were analyzed in the subset of patients with HCC and hepatic cirrhosis who completed SBRT as a bridge to liver transplant. Model of End-Stage Liver Disease (MELD-Na) was used to score hepatic function before and after SBRT. Results: With a median follow-up of 23 months (range: 3–40 months), 23 HCC patients (26 lesions treated) and 9 patients (14 lesions treated) with hepatic metastases received SBRT (mean dose: 48 Gy, range: 36–54 Gy) in 1–5 fractions. Nearly all patients in this study had pe-existing liver conditions, including hepatic cirrhosis (23), prior TACE (7), prior SBRT (18), or history of hepatic resection (2). Compared to the non-contrast images, SPIONs improved tumor visibility on post-SPION images on the background of negatively enhancing functionally active hepatic parenchyma. Prolonged SPION-contrast retention within hepatic parenchyma enabled per-fraction treatment adaptation throughout the entire multi-fraction treatment course. FLV loss (53%, p < 0.0001) was observed in cirrhotic patients, but functional and anatomic liver volumes remained consistent in non-cirrhotic patients. Mean dose to FLV was maintained within the liver threshold tolerance to radiation in all patients after the optimization of Step-and-Shoot Intensity-Modulated Radiotherapy (SS-IMRT) on the SPION-enhanced MRI-Linac. No radiation-induced liver disease was observed within 6 months post-SBRT, and the MELD-Na score in cirrhotic patients was not significantly elevated at 3-month intervals after SBRT completion. Conclusions: SPION Ferumoxytol^® administered intravenously as an alternative MRI contrast agent on the day of SBRT planning produces a long-lasting contrast effect between tumors and functional hepatic parenchyma for precision targeting and guided avoidance during the entire course of liver SBRT, enabling fast and accurate online plan adaptation on the 1.5 T Elekta Unity MR-Linac. This approach demonstrates a safe and effective bridging therapy for patients with hepatic cirrhosis, leading to low toxicity and favorable transplant outcomes. Full article

Background/Objectives: Pancreatic cancer is a very aggressive disease with a poor prognosis, even when diagnosed at an early stage. This study aimed to validate and refine a radiomic-based [¹⁸F]FDG-PET model to predict distant relapse-free survival (DRFS) in patients with unresectable locally advanced pancreatic cancer (LAPC). Methods: A Cox regression model incorporating two radiomic features (RFs) and cancer stage (III vs. IV) was temporally validated using a larger cohort (215 patients treated between 2005–2022). Patients received concurrent chemoradiotherapy with capecitabine and hypo-fractionated Intensity Modulated Radiotherapy (IMRT). Data were split into training (145 patients, 2005–2017) and validation (70 patients, 2017–2022) groups. Seventy-eight RFs were extracted, harmonized, and analyzed using machine learning to develop refined models. Results: The model incorporating Statistical-Percentile10, Morphological-ComShift, and stage demonstrated moderate predictive accuracy (training: C-index = 0.632; validation: C-index = 0.590). When simplified to include only Statistical-Percentile10, performance improved slightly in the validation group (C-index = 0.601). Adding GLSZM3D-grayLevelVariance to Statistical-Percentile10, while excluding Morphological-ComShift, further enhanced accuracy (training: C-index = 0.654; validation: C-index = 0.623). Despite these refinements, all versions showed similar moderate ability to stratify patients into risk classes. Conclusions: [¹⁸F]FDG-PET radiomic features are robust predictors of DRFS after chemoradiotherapy in LAPC. Despite moderate performance, these models hold promise for patient risk stratification. Further validation with external cohorts is ongoing. Full article

Background: Ionizing radiation (IR) exposure poses a significant health risk due to its widespread use in medical diagnostics and therapeutic applications, necessitating rapid and effective biomarkers for assessment. Objective: The aim of this study is to identify the serum proteomic signature of IR exposure in patients undergoing radiotherapy (RT). Methods: Blood samples were obtained from eighteen patients with head and neck cancer (HNC) and five patients with rectal cancer before and immediately after they underwent curative intensity-modulated radiotherapy (IMRT). The comprehensive serum proteome was analyzed in individual samples using nanoHPLC-MS/MS. Results: Forty radiation-modulated proteins (RMPs), 24 upregulated and 16 downregulated, with a fold change ≥1.5 and p-value < 0.05 were identified. About 40% of the RMPs are involved in acute phase response, DNA repair, and inflammation; the key RMPs were ADCY1, HGF, MCEMP1, CHD4, RECQL5, MSH6, and ZNF224. Conclusions: This study identifies a panel of serum proteins that may reflect the radiation response, providing a valuable molecular fingerprint of IR exposure and paving the way for the development of sensitive and specific biomarkers for early detection and clinical management of IR-related injuries. Full article