Multiple brain metastases single-isocenter stereotactic radiosurgery (SRS) treatment is increasingly employed in radiotherapy department. Before its use in clinical routine, it is recommended to perform end-to-end tests. In this work, we report the results of five HyperArc^TM treatment plans obtained by both ionization chamber (IC) and polymer gel. The end-to-end tests were performed using a water equivalent Mobius Verification Phantom^TM (MVP) and a 3D-printed anthropomorphic head phantom PseudoPatient^® (PP) (RTsafe P.C., Athens, Greece); 2D and 3D dose distributions were evaluated on the PP phantom using polymer gel (RTsafe). Gels were read by 1.5T magnetic resonance imaging (MRI). Comparison between calculated and measured distributions was performed using gamma index passing rate evaluation by different criteria (5% 2 mm, 3% 2 mm, 5% 1 mm). Mean point dose differences of 1.01% [min −0.77%–max 2.89%] and 0.23% [min 0.01%–max 2.81%] were found in MVP and PP phantoms, respectively. For each target volume, the obtained results in terms of gamma index passing rate show an agreement >95% with 5% 2 mm and 3% 2 mm criteria for both 2D and 3D distributions. The obtained results confirmed that the use of a single isocenter for multiple lesions reduces the treatment time without compromising accuracy, even in the case of target volumes that are quite distant from the isocenter.

This study investigates Intraobserver Features Variability (IFV) in radiomics studies and assesses the effectiveness of the ComBat harmonization method in mitigating these effects. Methods: This study utilizes data from the NSCLC-Radiomics-Interobserver1 dataset, comprising CT scans of 22 Non-Small Cell Lung Cancer (NSCLC) patients, with multiple Gross Tumor Volume (GTV) delineations performed by five radiation oncologists. Segmentation was completed manually (“vis”) or by autosegmentation with manual editing (“auto”). A total of 1229 radiomic features were extracted from each GTV, segmentation method, and oncologist. Features extracted included first order, shape, GLCM, GLRLM, GLSZM, and GLDM from original, wavelet-filtered, and LoG-filtered images. Results: Before implementing ComBat harmonization, 83% of features exhibited p-values below 0.05 in the “vis” approach; this percentage decreased to 34% post-harmonization. Similarly, for the “auto” approach, 75% of features demonstrated statistical significance prior to ComBat, but this figure declined to 33% after its application. Among a subset of three expert radiation oncologists, percentages changed from 77% to 25% for “vis” contouring and from 64% to 23% for “auto” contouring. This study demonstrates that ComBat harmonization could effectively reduce IFV, enhancing the feasibility of multicenter radiomics studies. It also highlights the significant impact of physician experience on radiomics analysis outcomes.

This study assessed the accuracy of average glandular dose (AGD) calculations for two Selenia Dimensions mammography systems using data from the online dose management DoseWatch software version 3.3.5.1. Mammographic images acquired between January 2021 and December 2022 were retrospectively analyzed. The AGD values displayed by the systems were compared with those independently calculated using the Dance and Boone methods. Additionally, real glandular composition of breast was estimated using LIBRA (Laboratory for Individualized Breast Radiodensity Assessment) software version 1.0.4 for a selected subgroup of patients. Results showed that the AGD values displayed by the systems were generally consistent with those calculated using the Dance method, but discrepancies emerged when applying the Boone method, especially when using estimated glandular composition. Most mammograms fell within acceptable and achievable dose limits according to European guidelines, though a small percentage exceeded these thresholds. The findings suggest that the Dance method, using glandular composition estimated through LIBRA, provides a reliable and accurate AGD calculation, offering a simpler alternative to more complex individualized calculations. The study highlights the importance of accurate glandularity estimation for proper dose management in mammography.

Thermoluminescent dosimeters (TLD) and optically stimulated luminescent dosimeters (OSLD) are practical, accurate, and precise tools for point dosimetry in medical physics applications. The objective of this study is to investigate the luminescence properties—both OSL and TL—of lithium fluoride (LiF) doped with magnesium (Mg), copper (Cu), and phosphorous (P) (LiF: Mg, Cu, P), commercially known as TLD-100H. The goal is to devise a methodological approach for dose measurement that allows for obtaining two independently measured dose values at each irradiation point, thereby improving accuracy and precision. The luminescence properties of TLD-100H were studied using a beta irradiation source (90Sr/90Y) integrated into the TL/OSL DA-15 automated Risø reader. This study identified the ideal experimental conditions for optimal dose evaluation and used them for dosimeter calibration across doses ranging from 0.5 to 4.0 Gy. The results demonstrated that, under optimal measurement parameters, the OSL and residual thermoluminescence (ResTL) signals—correlated to two trap systems within the dosimeter—exhibited high reproducibility, stability over multiple cycles, and high precision and accuracy (≤2%). Specifically, the OSL response showed good linear behavior across the investigated dose range, while the ResTL signal exhibited linear behavior between 0.5 and 2 Gy and sublinear behavior for doses >2 Gy.

Breast-conserving surgery followed by external beam Radiotherapy (RT) is a standard approach for early-stage Breast Cancer (BC). This retrospective study aims to determine the risk of RT-induced lung cancer for both standard and hypofractionated treatments. Fifty-eight Sicilian women treated at Humanitas Istituto Clinico Catanese (Misterbianco, Italy) between 2015 and 2021 with standard fractionated 3D-CRT (50 Gy in 2 Gy/fraction) were included. All treatment plans were designed using a hypofractionated schedule (42.56 Gy in 2.66 Gy/fraction). An Eclipse™ plug-in script was developed using the Eclipse Scripting Application Programming Interface (ESAPI) to extract patient and treatment data from the Treatment Planning System and compute Organ At Risk (OAR) volume, Organ Equivalent Dose (OED), Excess Absolute Risk (EAR), and Lifetime Attributable Risk (LAR) using the Schneider Mechanistic Model and reference data from regional populations, A-bomb survivors, and patients with Hodgkin’s Disease (HD). The OED distributions exhibited a statistically significant shift toward higher values in standard fractionated plans (p < 0.01, one-tailed paired Student’s t-test), leading to increased EAR and LAR. These results indicate that hypofractionated treatment may lower the risk of radiation-induced lung cancer. The feasibility of a priori risk estimation was evaluated by integrating the script into the TPS, allowing rapid comparison of SF and HF plans during planning.