OBJECTIVE: Surgically targeted radiation therapy (STaRT) with Cesium-131 seeds embedded in a collagen tile is a promising treatment for recurrent brain metastasis. In this study, the biological effective doses (BED) for normal and target tissues from STaRT plans were compared with those of external beam radiotherapy (EBRT) modalities.
METHODS: Nine patients (n = 9) with 12 resection cavities (RCs) who underwent STaRT (cumulative physical dose of 60 Gy to a depth of 5 mm from the RC edge) were replanned with CyberKnifeⓇ (CK), Gamma KnifeⓇ (GK), and intensity modulated proton therapy (IMPT) using an SRT approach (30 Gy in 5 fractions). Statistical significance comparing D95% and D90% in BED10Gy (BED10Gy95% and BED10Gy90%) and to RC + 0 to + 5 mm expansion margins, and parameters associated with radiation necrosis risk (V83Gy, V103Gy, V123Gy and V243Gy) to the normal brain were evaluated by a Wilcoxon-signed rank test.
RESULTS: For RC + 0 mm, median BED10Gy 90% for STaRT (90.1 Gy10, range: 64.1-140.9 Gy10) was significantly higher than CK (74.3 Gy10, range:59.3-80.4 Gy10, p = 0.04), GK (69.4 Gy10, range: 59.8-77.1 Gy10, p = 0.005), and IMPT (49.3 Gy10, range: 49.0-49.7 Gy10, p = 0.003), respectively. However, for the RC + 5 mm, the median BED10Gy 90% for STaRT (34.1 Gy10, range: 22.2-59.7 Gy10) was significantly lower than CK (44.3 Gy10, range: 37.8-52.4 Gy10), and IMPT (46.6 Gy10, range: 45.1-48.5 Gy10), respectively, but not significantly different from GK (34.1 Gy10, range: 22.8-47.0 Gy10). The median V243Gy was significantly higher in CK (11.7 cc, range: 4.7-20.1 cc), GK(6.2 cc, range: 2.3-11.9 cc) and IMPT (19.9 cc, range: 11.1-36.6 cc) compared to STaRT (1.1 cc, range: 0.0-7.8 cc) (p < 0.01).
CONCLUSIONS: This comparative analysis suggests a STaRT approach may treat recurrent brain tumors effectively via delivery of higher radiation doses with equivalent or greater BED up to at least 3 mm from the RC edge as compared to EBRT approaches.

OBJECTIVE: Stereotactic ablative body radiotherapy (SABR) is increasingly used for early-stage lung cancer, however the impact of dose to the heart and cardiac substructures remains largely unknown. The study investigated doses received by cardiac substructures in SABR patients and impact on survival.
METHODS: SSBROC is an Australian multi-centre phase II prospective study of SABR for stage I non-small cell lung cancer. Patients were treated between 2013 and 2019 across 9 centres. In this secondary analysis of the dataset, a previously published and locally developed open-source hybrid deep learning cardiac substructure automatic segmentation tool was deployed on the planning CTs of 117 trial patients. Physical doses to 18 cardiac structures and EQD2 converted doses (α/β = 3) were calculated. Endpoints evaluated include pericardial effusion and overall survival. Associations between cardiac doses and survival were analysed with the Kaplan-Meier method and Cox proportional hazards models.
RESULTS: Cardiac structures that received the highest physical mean doses were superior vena cava (22.5 Gy) and sinoatrial node (18.3 Gy). The highest physical maximum dose was received by the heart (51.7 Gy) and right atrium (45.3 Gy). Three patients developed grade 2, and one grade 3 pericardial effusion. The cohort receiving higher than median mean heart dose (MHD) had poorer survival compared to those who received below median MHD (p = 0.00004). On multivariable Cox analysis, male gender and maximum dose to ascending aorta were significant for worse survival.
CONCLUSIONS: Patients treated with lung SABR may receive high doses to cardiac substructures. Dichotomising the patients according to median mean heart dose showed a clear difference in survival. On multivariable analyses gender and dose to ascending aorta were significant for survival, however cardiac substructure dosimetry and outcomes should be further explored in larger studies.

Juntendo University Hospital is the second hospital in Japan to start stereotactic brain irradiation using linear accelerator (LINAC) system. This report details the historical transition of stereotactic irradiation, progress of treatment technology, and change of treatment method from the beginning to the Juntendo University Hospital and Juntendo Nerima Hospital. The hospital changed the use of cobalt to the LINAC system when it was rebuilt in 1993. Total body irradiation treatment for leukemia had started around the same time. A year later, in 1994, the hospital used their LINAC systems to perform stereotactic head irradiation, otherwise known as pinpoint irradiation. In 2005, Juntendo University Nerima Hospital was opened and in September of the same year, radiation therapy using the latest model of LINAC system at that time was initiated. This was the first among all Juntendo hospitals to start intensity-modulated radiation therapy (IMRT) and image-guided radiotherapy (IGRT). In 2014, a second LINAC system for IMRT and IGRT was equipped at the Juntendo Hongo Hospital. In 2021, the LINAC systems of the Juntendo University Nerima Hospital were replaced after 15 years of usage. The new method of SRS was started using a latest LINAC systems. In this paper, I introduce the technique and progress of SRS that I have experienced mainly in Juntendo University.

UNASSIGNED: The aim of our study was to compare dosimetric aspects of three radioablation modalities - direct high-dose-rate brachytherapy (HDR-BT) and virtually planned stereotactic body radiation therapy performed on CyberKnife (SBRTck) and Elekta Versa HD LINAC (SBRTe) applied in patients with liver metastases.
UNASSIGNED: We selected 30 patients with liver metastases, who received liver interstitial HDR-BT and virtually prepared plans for SBRTck and SBRTe. In all the cases, the prescribed dose was a single fraction of 25 Gy. Treatment delivery time, doses delivered to PTV and organs at risk, as well as conformity indices, were calculated and compared.
UNASSIGNED: The longest median treatment delivery time was observed in SBRTck in contrast to HDR-BT and SBRTe which were significantly shorter and comparable. HDR-BT plans achieved better coverage of PTV (except for D98%) in contrast to SBRT modalities. Between both SBRT modalities, SBRTck plans resulted in better dose coverage in Dmean, D50%, and D90% values compared to SBRTe without difference in D98%. The SBRTe was the most advantageous considering the PCI and R100%. SBRTck plans achieved the best HI, while R50% value was comparable between SBRTe and SBRTck. The lowest median doses delivered to uninvolved liver volume (V5Gy, V9.1Gy) were achieved with HDR-BT, while the difference between SBRT modalities was insignificant. SBRT plans were better regarding more favourable dose distribution in the duodenum and right kidney, while HDR-BT achieved lower doses in the stomach, heart, great vessels, ribs, skin and spinal cord. There were no significant differences in bowel and biliary tract dose distribution between all selected modalities.
UNASSIGNED: HDR-BT resulted in more favourable dose distribution within PTVs and lower doses in organs at risk, which suggests that this treatment modality could be regarded as an alternative to other local ablative therapies in carefully selected patients\' with liver malignancies. Future studies should further address the issue of comparing treatment modalities in different liver locations and clinical scenarios.

BACKGROUND: Stereotactic body radiotherapy (SBRT) has firmly established its role in stage I NSCLC. Clinical trial results may not fully apply to real-world scenarios. This study aimed to uncover the real-world incidence of acute toxicity and 90-day mortality in patients with SBRT-treated stage I NSCLC and develop prediction models for these outcomes.
METHODS: Prospective data from the Dutch Lung Cancer Audit for Radiotherapy (DLCA-R) were collected nationally. Patients with stage I NSCLC (cT1-2aN0M0) treated with SBRT in 2017 to 2021 were included. Acute toxicity was assessed, defined as grade greater than or equal to 2 radiation pneumonitis or grade greater than or equal to 3 non-hematologic toxicity less than or equal to 90 days after SBRT. Prediction models for acute toxicity and 90-day mortality were developed and internally validated.
RESULTS: Among 7279 patients, the mean age was 72.5 years, with 21.6% being above 80 years. Most were male (50.7%), had WHO scores 0 to 1 (73.3%), and had cT1a-b tumors (64.6%), predominantly in the upper lobes (65.2%). Acute toxicity was observed in 280 (3.8%) of patients and 90-day mortality in 122 (1.7%). Predictors for acute toxicity included WHO greater than or equal to 2, lower forced expiratory volume in 1 second and diffusion capacity for carbon monoxide, no pathology confirmation, middle or lower lobe tumor location, cT1c-cT2a stage, and higher mean lung dose (c-statistic 0.68). Male sex, WHO greater than or equal to 2, and acute toxicity predicted higher 90-day mortality (c-statistic 0.73).
CONCLUSIONS: This nationwide study revealed a low rate of acute toxicity and an acceptable 90-day mortality rate in patients with SBRT-treated stage I NSCLC. Notably, advanced age did not increase acute toxicity or mortality risk. Our predictive models, with satisfactory performance, offer valuable tools for identifying high-risk patients.

UNASSIGNED: Uveal melanoma (UM) is the most common primary ocular malignancy. We compared fractionated stereotactic radiotherapy (SRT) with proton therapy, including toxicity risks for UM patients.
UNASSIGNED: For a total of 66 UM patients from a single center, SRT dose distributions were compared to protons using the same planning CT. Fourteen dose-volume parameters were compared in 2-Gy equivalent dose per fraction (EQD2). Four toxicity profiles were evaluated: maculopathy, optic-neuropathy, visual acuity impairment (Profile I); neovascular glaucoma (Profile II); radiation-induced retinopathy (Profile III); and dry-eye syndrome (Profile IV). For Profile III, retina Mercator maps were generated to visualize the geographical location of dose differences.
UNASSIGNED: In 9/66 cases, (14 %) proton plans were superior for all dose-volume parameters. Higher T stages benefited more from protons in Profile I, especially tumors located within 3 mm or less from the optic nerve. In Profile II, only 9/66 cases resulted in a better proton plan. In Profile III, better retina volume sparing was always achievable with protons, with a larger gain for T3 tumors. In Profile IV, protons always reduced the risk of toxicity with a median RBE-weighted EQD2 reduction of 15.3 Gy.
UNASSIGNED: This study reports the first side-by-side imaging-based planning comparison between protons and SRT for UM patients. Globally, while protons appear almost always better regarding the risk of optic-neuropathy, retinopathy and dry-eye syndrome, for other toxicity like neovascular glaucoma, a plan comparison is warranted. Choice would depend on the prioritization of risks.

OBJECTIVE: Hearing loss is a common symptom associated with vestibular schwannoma (VS), either because of the tumor\'s effects on the cochlear nerve or due to active treatments such as surgery or stereotactic radiosurgery (SRS). Treatment decisions for VS are based on factors including tumor size, hearing status, patient symptoms, and institutional preference. The study aimed to investigate long-term auditory outcomes in VS patients undergoing active treatments with a hearing preservation intent.
METHODS: A systematic literature review was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, searching Scopus, Pubmed, and Web of Science databases from inception to January 2024.
METHODS: Studies meeting inclusion criteria, including a minimum 5-year follow-up and assessment of pre- and posttreatment hearing outcomes, were included. Pooled prevalence estimates for serviceable hearing after SRS and microsurgery were calculated using MetaXL software. Risk of bias assessment was performed with the Risk of Bias in Non-randomized Studies of Interventions tool.
RESULTS: Nine studies met the inclusion criteria, with 356 patients included for analysis. The pooled prevalence of maintaining serviceable hearing after SRS at 10 years was 18.1% (95% confidence interval [CI]: 1.7%-43.3%), with wide prediction intervals indicating variability in outcomes. Microsurgery demonstrated a higher prevalence of maintaining long-term serviceable hearing, with a pooled estimate of 74.5% (95% CI: 63.5%-84.1%).
CONCLUSIONS: This systematic review underscores the importance of long-term follow-up in evaluating auditory outcomes in VS treatment. Despite the biases inherent to pretreatment patients selection, hearing preservation microsurgery for sporadic VS removal demonstrated favorable and stable long-term serviceable hearing.

UNASSIGNED: Evaluate effectiveness and safety of multiple HyperArc courses and patterns of progression in patients affected by BMs with intracranial progression.
UNASSIGNED: 56 patients were treated for 702 BMs with 197 (range 2-8) HyperArc courses in case of exclusive intracranial progression. Primary end-point was the overall survival (OS), secondary end-points were intracranial progression-free survival (iPFS), toxicity, local control (LC), neurological death (ND), and whole-brain RT (WBRT)-free survival. Site of progression was evaluated against isodoses levels (0, 1, 2, 3, 5, 7, 8, 10, 13, 15, 20, and 24 Gy.).
UNASSIGNED: The 1-year OS was 70 %, and the median was 20.8 months (17-36). At the univariate analysis (UVA) biological equivalent dose (BED) > 51.3 Gy and non-melanoma histology significantly correlated with OS. The median time to iPFS was 4.9 months, and the 1-year iPFS was 15 %. Globally, 538 new BMs occurred after the first HA cycle in patients with extracranial disease controlled. 96.4 % of them occurred within the isodoses range 0-7 Gy as follows: 26.6 % (0 Gy), 16.5 % (1 Gy), 16.5 % (2 Gy), 20.1 % (3 Gy), 13.1 % (5 Gy), 3.4 % (7 Gy) (p = 0.00). Radionecrosis occurred in 2 metastases (0.28 %). No clinical toxicity of grade 3 or higher occurred during follow-up. One- and 2-year LC was 90 % and 79 %, respectively. At the UVA BED > 70 Gy and non-melanoma histology were significant predictors of higher LC. The 2-year WBRT-free survival was 70 %. After a median follow-up of 17.4 months, 12 patients deceased by ND.
UNASSIGNED: Intracranical relapses can be safely and effectively treated with repeated HyperArc, with the aim to postpone or avoid WBRT. Diffuse dose by volumetric RT might reduce microscopic disease also at relatively low levels, potentially acting as a virtual CTV. Neurological death is not the most common cause of death in this population, which highlights the impact of extracranial disease on overall survival.

UNASSIGNED: The aim of the study was to evaluate the efficacy of stereotactic body radiotherapy (SBRT) using the CyberKnife-M6 (CK-M6) with lung optimized treatment (LOT) module in patients with primary lung cancer and lung metastases.
UNASSIGNED: Forty-two lesions from 35 patients were treated between 2019 and 2022. Four-dimensional computed tomography images were obtained when the patients were in a free breathing modality. Tracking modality was selected prospectively according to the visibility of the target. The median prescribed dose was 48 Gy in four fractions (fx) (28 - 55 Gy/1- 7 fx). The median age was 68 years (47 - 82 years), and 43% of cases were adenocarcinoma. The median lesion size was 15 mm (6 - 36 mm).
UNASSIGNED: Complete, partial and stable responses were obtained as 26%, 62%, and 9.5% at a median of 2 months (1 - 6 months), and 35.5%, 47.5% and 5% at the 12th month evaluation, respectively. Grade 3 and higher toxicity was not observed in any case. The mean and 2-year overall survival (OS) was 31.5 months and 54%, and the local recurrence-free survival (LRFS) was 29.6 months and 51%, respectively. In univariate analysis, target lesion type, complete response (CR), and higher esophagus maximum dose were favorable factors for OS and LRFS (P < 0.05). The CR at 12th month evaluation remained significant in multivariate analysis in terms of OS (hazard ratio = 8.602, 95% confidence interval: 1.05 - 70.01; P = 0.044).
UNASSIGNED: A mean LRFS of 29.6 months and OS of 31.5 months were obtained in patients with primary and metastatic lung cancer. With a median treatment time of 25 min, motion-managed strategy with CK-M6-LOT-based SBRT is an effective, safe, and comfortable treatment method for lung cancer.

UNASSIGNED: Osteolytic spinal metastases (SM) have a higher risk of fracture. In this study we aim to confirm the remineralization of lytic SM after radiation therapy. Secondary the influence of SBRT compared to cEBRT and tumor type will be analyzed.
UNASSIGNED: A retrospective cohort study was performed.
UNASSIGNED: 87 patients, 100 SM were included. 29 received SBRT, 71 cEBRT. Most common primary tumors were breast (35 %), lung (26 %) and renal (11 %). Both cEBRT and SBRT resulted in a significant increase of bone mineral density (BMD) (83.76 HU ± 5.72 → 241.41 HU ± 22.58 (p < 0.001) and 82.45 ± 9.13 → 179.38 ± 47.83p = 0.026). There was a significant increase in absolute difference of BMD between the SM and reference vertebrae (p < 0.001). There was no significant difference between SBRT and cEBRT. There was no increase of BMD in renal lytic SM after radiation therapy (pre-treatment: 85.96 HU ± 19.07; 3 m 92.00 HU ± 21.86 (p = 0.882); 6 m 92.06 HU ± 23.94 (p = 0.902); 9 m 70.44 HU ± 7.45 (p = 0.213); 12 m 98.08 HU ± 11.24 (p = 0.740)). In all other primary tumors, a significant increase of BMD after radiation therapy was demonstrated (p < 0,05).
UNASSIGNED: We conclude that the BMD of lytic SM increases significantly after radiation therapy. Lytic SM of primary renal tumors are the exception; there is no significant remineralization of renal lytic SM after radiation therapy. There is no benefit of SBRT over cEBRT in this remineralization. These findings should be taken into account when deciding on surgery in the potentially unstable group defined by the spinal instability neoplastic score.