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Background: Model‐based dose calculation algorithms (MBDCA), such as the Advanced Collapsed cone Engine (ACE) in Oncentra Brachy® can be used to overcome the limitations of the TG‐43 formalism. ACE is a point kernel superposition algorithm that calculates the total dose separated into primary, first‐scatter, and multiple‐scatter dose. Albeit ACE yields accurate results under most circumstances, several studies have reported underestimations of the dose to cortical bone. These underestimations are likely caused by approximations in the handling of multiple‐scatter dose for non‐water media. Such would result in noticeable deviations where the multiple‐scatter is a considerable fraction of the total dose, that is, at greater distances from the source. Purpose: To improve and test the accuracy of the multiple‐scatter dose component in the ACE algorithm to remedy its inaccuracy for non‐water geometries. Methods: A careful analysis of the transport and absorption of the multiple‐scatter energy fluence revealed an inconsistency in the scaling of energy absorption ratios for non‐water media of the multiple‐scatter kernel. We implemented an updated algorithm version, ACEcorr, and tested it for three different geometries. All had a single 192Ir‐source at the center of a cubic water phantom with a box‐shaped heterogeneity of either cortical bone or air, positioned at different distances from the source. Dose distributions for the three cases were calculated with ACE and ACEcorr and compared to Monte Carlo simulations, using the percentage dose difference ratio as figure‐of‐merit. All dose calculation methods scored separately the dose deposited by primary, first‐scattered, and multiple‐scattered photons. Results: The accuracy of the updated algorithm ACEcorr was superior to ACE. In the cortical bone heterogeneity, the mean percentage dose difference ratio for the total dose improved from −11.7%$ - 11.7{\mathrm{\% }}$ to −2.2%$ - 2.2{\mathrm{\% }}$ (in the worst case) by our update. Less impact was seen in the air heterogeneity, where both ACE and ACEcorr deviated less than 2% from the Monte Carlo results. The algorithm update mainly concerns the multiple‐scattered dose component, but an accompanying data processing update also had a small effect (≤$ \le $0.5% difference) on the primary and first‐scattered dose. The calculation times were not affected. Conclusions: The updates to ACE improved the accuracy of multiple‐scatter dose calculation for non‐water media, without increasing calculation times. [ABSTRACT FROM AUTHOR]

BackgroundMethodsResultsConclusionsReport the results of Ruthenium plaque brachytherapy (106Ru) for the management of intraocular tumors in Thailand.We retrospectively reviewed the medical records of 46 eyes of 45 patients who received 106Ru brachytherapy for the treatment of various intraocular tumors in the Department of Ophthalmology of Ramathibodi Hospital, Mahidol University, Bangkok, Thailand, between April 2013 and December 2020.Of 46 eyes, 21 (46%) were diagnosed with small to medium choroidal melanoma, 13 (28%) with retinoblastoma, 4 (9%) with choroidal metastases, 2 (4%) with retinal vasoproliferative tumor (VPT), 3 (7%) with choroidal hemangioma (CH), 2 (4%) with RPE adenoma, and 1 (2%) with retinal hemangioblastoma. The mean tumor thickness was 4.8 mm (range, 2.4–6.6). After a mean follow-up of 62.4 months (range, 4.8–122.7), local tumor control was achieved in 39 eyes (85%), which were 100% for choroidal melanoma, 46% for RB, 100% for choroidal metastasis and 100% for benign tumors. Radiation-related complications were found in 28 eyes (61%), including cataracts in 10 (25%), radiation retinopathy in 14 (30%), radiation maculopathy in 14 (30%), radiation papillopathy in 6 (13%), and vitreous hemorrhage in 3 (7%) eyes. All patients with retinoblastoma currently alive without metastasis. Two patients with choroidal melanoma developed systemic metastases and three patients with choroidal metastases died at the end of the study.Patients with intraocular tumors treated with 106Ru brachytherapy showed excellent outcomes in relation to tumor control with few complications. [ABSTRACT FROM AUTHOR]

Purpose: This randomized controlled study was conducted to analyze the effect of hand massage on the fatigue level of the women receiving brachytherapy. Methods: It was determined that 12 patients were included in each group (control and hand massage group), so 24 women with gynecologic cancer were included in the study. The application was performed on each hand for 5 min, a total of 10 min in hand massage group. Hand massage was applied before each brachytherapy (at the first, second, and third sessions, a total of three times) every other day for 1 week in the hand massage group. No intervention was performed to the control group during the study. The data were collected using the Patient Information Form and Brief Fatigue Inventory (BFI). Results: At the end of the brachytherapy, the fatigue severity score and impact of fatigue on activities of daily living scores of the group that applied hand massage were determined to be lower than the control group (p < 0.05). Conclusion: It was determined that hand massage effectively controlled fatigue and the impact of fatigue on activities of daily living. Hand massage is a safe and economical method that can be performed by certified nurses. Trial registration: This clinical trial is registered at ClinicalTrials.gov (NCT06056713-09/21/2023). [ABSTRACT FROM AUTHOR]

Background: High dose rate (HDR) intracavitary brachytherapy (ICBT) plays a crucial role in cervix cancer treatment, with variations in fractionation schedules across different radiation societies. This study aims to assess the effectiveness and tolerability of a 7 Gy per fraction twice daily schedule over two successive weeks versus an 8 Gy per fraction once weekly schedule over three successive weeks. Patients and Methods: From 2020 to 2022, 87 patients with uterine cervix cancer (Stages II and III) underwent concomitant external beam radiotherapy (EBRT) and chemotherapy, followed by HDR-ICBT. Patients were randomised into two arms: Arm A (8 Gy per fraction once weekly for 3 fractions) and Arm B (7 Gy per fraction twice daily once a week for 4 fractions). Local control is defined as any patient free from local progression (CR + PR + SD) in the first year after ending brachytherapy (BTH). Results: The median follow-up was 16·5 months. Local control at 1 year was 78·7% in Arm A and 89·2% in Arm B (p = 0·24). No clinically significant differences in rectal and bladder toxicities were observed between the two arms (p = 0·40). Conclusion: There were limited treatment machines and other BTH challenges in Egypt, and the HDR BTH schedule of 7 Gy per fraction twice daily over 2 successive weeks presents an acceptable alternative to the current national standard of 8 Gy per fraction once weekly over 3 weeks. Both schedules demonstrate comparable local control, late toxicity and progression-free survival. Notably, the 7 Gy per fraction twice daily per week for 4 fractions offers the advantage of a reduced total treatment time. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the clinicopathological characteristics and the effectiveness of post-operative high-dose-rate (HDR) interventional radiotherapy (IRT - brachytherapy) in managing advanced ocular surface squamous neoplasia (OSSN) and eyelid tumors. Methods: Nineteen patients with advanced malignancies affecting the ocular surface (stage ≥ T2) and eyelids (staging ≥ T3) were enrolled. Post-operative HDR-IRT treatment followed surgery after multidisciplinary discussion. In our series a total dose of 49 Gy was administered in 14 fractions of 3.5 Gy each, 2 doses per day. Local disease control is the study's main outcome. Death rate, total survival, disease-free survival, and toxicity are secondary outcomes. Results: Local recurrence was observed in 4 cases, 2 were conjunctival melanomas and 2 were conjunctival squamous cell carcinoma. The median OS was 56.3 months. The 12, 24 and 36 months survival rate was respectively 100.00% (IQR: 100.00% - 100.00%), 100.00% (IQR: 100.00% - 100.00%), 100.00% (IQR: 100.00% - 100.00%) respectively . The median DFS was 56.3 months. The 12, 24 and 36 months disease survival rate was respectively 85.71% (IQR: 69.21% - 100.00%), 68.57% (IQR: 42.11% - 100.00%), 68.57% (IQR: 42.11% - 100.00%) respectively. In eyelid tumors, madarosis and eyelid abnormalities are the main side effects, while in OSSNs, dry eye symptoms are frequently reported. Conclusion: Postoperative HDR-IRT has been effective in advanced eyelid cancers control. More challenging appears instead an effective treatment of advanced OSSNs, particularly conjunctival melanomas. Multicenter studies are needed to get a larger patient sample and to evaluate different radiotherapy dosages by different histologic and T types of tumors.

This article in the journal Pediatric Anesthesia discusses the challenges faced by anesthetists in managing pediatric patients undergoing brachytherapy for retinoblastoma. The study found that children experienced high levels of anxiety, and traditional interventions like parental presence and video distraction were not completely effective. Anesthesia techniques, postoperative pain management, and the need for experienced staff and careful planning were highlighted as crucial factors in ensuring a safe outcome for these patients. The study emphasizes the importance of a multimodal approach to address anxiety, pain, and other perioperative challenges in this population. [Extracted from the article]

Study aimed at Monte Carlo (MC) modeling and dosimetric validation of GammaMed Plus 192Ir source for high dose rate brachytherapy using Geant4 code in TOPAS. Study investigated the several TG-43 guided dosimetric parameters for brachytherapy dose calculation. The excellent agreement was found between simulated and published data. The simulated MC dataset can be served as reference and fed into Treatment planning system (TPS) to verify brachytherapy dose calculation. Present MC modeling of brachytherapy source can be availed in further patient specific studies involving MC simulation. • MC modeling of GammaMed Plus 192Ir source. • Simulation of brachytherapy dose calculation parameters. • Validation of dosimetric parameters. • Preclinical validation of TG-43 parameters. • Helps in determine treatment uncertainties. [ABSTRACT FROM AUTHOR]

Background: Radiation therapy is one of the main methods of treating and controlling tumors. Patient's quality of life is directly related to the accuracy of treatment provided. Recently, with the advancement of radiation therapy methods in order to achieve this target and quality of treatment, radiation therapy systems based on image guidance have been created. This new technology is known as Resonance Imaging with a Linear Accelerator (MR-Linac) device. The reason for choosing the Magnetic Resonance Imaging (MRI) system compared to other imaging systems is the quality and superiority of the soft tissue image. Today, in some advanced cancer treatment centers in the world, brachytherapy is performed in the presence of a magnetic field using MRI imaging. There are three types of responses for electron behavior under the influence of magnetic fields according to Lorentz force. When the field is perpendicular to the direction of the electron's movement, its path deviates, when it is parallel, it moves in the same direction, and when it has an angle with the field lines, it moves in a spiral path towards the magnetic field lines Direction. According to this principle, the dose distribution in the perpendicular or parallel magnetic field can be narrower or wider. The main purpose of this research is to investigate the effect of magnetic fields for the dose distribution of brachytherapy sources and the treatment planning algorithm under the guidance of MRI imaging. Materials and Methods: In this research, simulation is done using the Monte Carlo code. The computational space called homogeneous phantom consists of a cube with dimensions 6×6×6 cm, which consists of 216.000 cells with dimensions of 1 mm and water content. Considering the effective distance in brachytherapy treatments and in order to facilitate the analysis of the large volume of data to draw the isodose curves, a cubic meshing was defined along all three coordinate axes, and the dose changes in the longitudinal interval ±3cm on the sides of the center of the source were calculated. The output was drawn in the form of isodose curves by MATLAB software through Geant4 meshing method and the difference between the curves in the state with and without the presence of magnetic field was expressed by the Gamma Index parameter and with the criteria of 3% and 3 mm. Results: The error value for the dose obtained in the farthest cell from the center of the source as the maximum error was less than 5%, in other words, in the whole simulation, the error was below 5%. Conclusion: The effects of magnetic field on the dose distribution caused by iridium-192 and ytterbium-169 were observed to be ineffective, as a result, it is possible to ensure the safety of brachytherapy treatment with these sources in the presence of magnetic fields. However, regarding Cobalt-60 due to the dispersion of isodose curves in different field intensities, necessary considerations are recommended. [ABSTRACT FROM AUTHOR]

Background: To determine outcomes of MRI-assisted radiosurgery (MARS) for salvage brachytherapy using the radioisotope 103 Pd after various upfront treatments including surgery, external beam radiotherapy, and brachytherapy., Methods: We retrospectively reviewed data for patients who underwent salvage MARS for intraprostatic lesions or prostate bed recurrences from 2016 to 2022. Biochemical recurrence, prostate cancer-specific, and overall survival, and the cumulative incidences of toxicities, were determined by Kaplan-Meier estimates. Cox proportional hazards models were used to determine associations between clinical and treatment variables and risk of toxicity., Results: Study included 31 patients with local recurrence after initial definitive treatment. Four (13%) were initially treated with prostatectomy and salvage radiation, twenty-four (77%) with external beam radiation, and three with brachytherapy. Most had intermediate- or high-risk prostate cancer at the time of diagnosis. Twenty-two patients (71%) had focal-gland and nine (29%) had whole-gland MARS LDR salvage brachytherapy. Median follow-up was 35-28 months. By last follow-up, 5 patients (16%) experienced recurrence and started ADT, 3 patients started ADT before experiencing recurrence due to physician discretion, and 23 patients (74%) remained without recurrence. No patients died of prostate cancer. Median PSA nadir for recurrence-free patients was 0.2 ng/mL (range, 0-0.9 ng/mL). Grade 3 toxicities occurred in 4 patients (13%) including 3 patients (13%) with genitourinary events only and 1 patient (3%) with both a grade 3 genitourinary and a grade 3 gastrointestinal event., Conclusions: In this modern series of patients undergoing salvage MARS with 103 Pd, we observed acceptable toxicity and early, promising biochemical disease control. These findings highlight the broader applicability of salvage MARS regardless of upfront treatment modality., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Coronary artery in-stent restenosis (ISR) is driven by neointimal hyperplasia and neoatherosclerosis in previously placed stents. Drug eluting stents (DES) have been adopted as first line therapy for the initial episode of ISR. However, recurrent ISR has limited durable salvage options. In this article we review the pathophysiology, incidence, and management options of recurrent DES- ISR., Competing Interests: Declaration of competing interest COI/Disclosures: AG – None. OM – None. RP – Boston Scientific – speaker. Abiomed – speaker, consultant., (Copyright © 2024. Published by Elsevier Inc.)

Objective: Although single-fraction high-dose-rate brachytherapy (SFHDR-BT) for localized prostate cancer has been attempted in clinical trials, there is currently a lack of relevant medical evidence. It is essential to conduct a systematic analysis of the long-term safety and efficacy of SFHDR-BT. Materials and methods: Comprehensive and systematic searches for eligible studies were performed in PubMed, Embase, and the Cochrane Library databases. The primary endpoints included safety and efficacy, represented by toxic effects, biochemical recurrence-free survival (bRFS) and overall survival (OS), respectively. The proportion rates were used as the effect measure for each study and were presented with corresponding 95% confidence intervals (CI). Results: Eight studies met the inclusion criteria for quantitative analysis, including 552 patients. The median follow-up was 71.3 months (60-72.8 months). The estimates of cumulative occurrence for severe gastrointestinal (GI) and genitourinary (GU) toxic effects were 0 and 3% (95% CI 1-5%), respectively. The pooled cumulative incidence of grade ≥ 3 sexual dysfunction occurrence was 4% (95% CI 1-7%). The estimate of long term bRFS was 72% (95% CI 68-76%) and 90% (95% CI 85-95%) for long term OS. Conclusion: In general, SFHDR-BT is well tolerated and associated with suboptimal clinical benefit in patients with localized prostate cancer. High-quality prospective studies of SFHDR-BT are necessary to verify its safety and efficacy., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

The aim of this study was to evaluate the effect of nurse-physician collaboration on the incidence of complications, anxiety and depression, quality of life, and satisfaction with nursing care among cervical cancer patients undergoing three-dimensional intracavitary brachytherapy. In this randomized, single-blinded, placebo-controlled trial, 92 eligible cervical cancer patients were equally divided into two groups upon admission. The control group was given routine nursing, and the intervention group received a nurse-physician collaboration in addition to routine care. Anxiety, depression, and health-related quality of life in both groups were assessed and compared at baseline and discharge. The intervention group had significantly fewer complications and showed marked improvements in mental health and quality of life compared to the control group. Satisfaction with nursing care was substantially greater in the intervention group. These results support the clinical adoption of a nurse-physician collaborative care model in the management of cervical cancer with three-dimensional intracavitary brachytherapy.

Purpose: Radiation-induced scleral necrosis (RISN) is a less frequent complication of brachytherapy for uveal melanoma, and may require surgical treatment in selected cases. We aimed to identify the prognostic factors for RISN treatment., Methods: All patients with brachytherapy for uveal melanoma treated at our institution between 01/1999 and 12/2016 who developed RISN were followed until 02/2021. Various parameters were evaluated through univariable and multivariable Cox regression analysis. The surgical intervention due to RISN was the principal outcome event of this study., Results: Of 115 patients in the final cohort, 51 individuals (44%) underwent RISN treatment (conjunctival revision [n = 2], patching [n = 46] or enucleation [n = 3]) at median 1.80 months after RISN occurrence. Significant RISN characteristics were summarized into a novel RISN severity scale - Grade I: largest diameter ≤ 5 mm and no progression; Grade II: largest diameter > 5 mm or any progression during the follow-up; Grade III: presence of uveal prolapse; and Grade IV: leakage through open eyewall perforation. In the multivariable analysis, the RISN severity scale (aHR = 2.37 per grade increase, p = 0.01) and the time between brachytherapy and RISN occurrence (<15 months, aHR = 6.33, p < 0.0001) were independently associated with the study endpoint. The RISN severity scale showed high diagnostic accuracy for prediction of RISN treatment (AUC = 0.869)., Conclusions: In our series, about the half of RISN cases underwent surgical treatment. The presented novel severity scale for RISN might become a helpful tool for clinical management of individuals with RISN. We recommend external validation of the diagnostic accuracy of the presented scale., Competing Interests: Declaration of conflicting interestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.