PURPOSE:Trials show similar pain outcomes for hypofractionated and multi-fraction regimens in bone metastases, yet clinical adoption of hypofractionation remains limited. The coronavirus disease 2019 (COVID-19) pandemic may have increased hypofractionation to minimize hospital visits and optimize resources. This study evaluated fractionation patterns before, during and after COVID-19 and compared pain outcomes between regimens in routine practice. MATERIALS AND METHODS:Data on treatment regimens for bone metastases between 2018 and 2022 were collected from 11 of 22 Dutch radiotherapy departments. Trends in utilization of hypofractionated (1-2 times 8 Gy) and multi-fraction (≥5 fractions) regimens were analyzed. For a subset of patients (n = 278), self-reported pain scores were collected at baseline, 4 and 8 weeks, and 3 months. Pain scores and pain response were compared for hypofractionated and multiple-fraction regimens, with complete (pain score 0) or partial (reduction ≥2 points) response classified as responders. RESULTS:A total of 17,336 patients were included, receiving 31,677 treatment regimens. The majority of the regimens were hypofractionated (n = 25,790, 81%). The use of hypofractionated regimens ranged from 34% to 99% between radiotherapy departments. A statistically significant increase in hypofractionated regimens was observed since the onset of the COVID-19 pandemic in 2020 (p < 0.001). In an exploratory analysis of patients with available pain scores, pain response in the three months post-treatment did not differ significantly between hypofractionated and multi-fraction regimens (56% vs. 63%, p = 0.406). CONCLUSION:This study demonstrates a high adoption of hypofractionated regimens, with a slight increase since the COVID-19 pandemic, though considerable variation remains between departments. Pain outcomes were comparable between hypofractionated and multi-fraction regimens, suggesting equal palliation and less treatment burden with hypofractionation.

Purpose:Stereotactic radiation therapy (SRT) is a frequently used and effective treatment for patients who received diagnosis for brain metastases (BMs). Radionecrosis (RN) is a severe complication of SRT which may cause neurologic symptoms. A normal tissue complication probability (NTCP) model has previously been established to predict the risk of RN based on the volume of healthy brain receiving ≥12 Gy. The aim of this study is to externally validate this prediction model. Methods and Materials:A total of 162 patients treated with SRT for solitary BMs were retrospectively included. The NTCP models for all (asymptomatic and symptomatic) RN and symptomatic RN cases were evaluated using discrimination (C-statistic) and calibration (Brier scores). Overall survival was determined using the Kaplan-Meier method. Results:Median overall survival was 10 months. Asymptomatic or symptomatic RN was found in 44 (27%) of patients. Of these, 26 (16%) RN cases were symptomatic, with actuarial rates of 11% and 22% after 6 and 12 months, respectively. The C-statistics of the "any RN" and the "symptomatic RN" models were identical (0.61). Brier scores were 0.201 and 0.217, respectively. Univariable logistic regression analysis showed a significant correlation between both tumor volume and volume of healthy brain receiving ≥12 Gy with symptomatic RN. These effects did not hold up in the multivariable analysis. A nomogram was established and internally validated. Conclusions:The accuracy of the tested NTCP models in assessing the risk of RN in patients with BM after SRT was insufficient for clinical practice. A novel multifactorial nomogram was developed to predict symptomatic RN. This model needs to be externally validated.

Background/Objectives: Neurosurgical resection is the standard treatment for large brain metastases (BMs). Postoperative stereotactic radiotherapy (SRT) is used to reduce local recurrence (LR) but does not always prevent leptomeningeal disease (LMD). This study aims to analyze patterns of tumor recurrence and to identify opportunities for the further improvement of treatment efficacy. Methods: We included 147 patients who underwent resection and SRT for BMs. The distance between the resection cavity target volume and the new tumor growth was calculated. Cox regression analyses were used to assess associations of LMD with various patient characteristics. Results: Median survival after postoperative SRT was 14 months (IQR 6–30) with a 3-year actuarial survival rate of 21%. LR occurred in 20/147 patients (14%). After total resection, LR occurred in 21% of patients after 3 years of follow-up compared to 36% after subtotal resection. Marginal LR occurred in 5/147 patients (3%). LMD was found in 21/147 patients (14%; 3-year actuarial rate, 26%), and it was found more commonly in patients with resected cerebellar metastases (23%; 3-year actuarial rate, 46%) compared to those with cerebral metastases (11%; 3-year actuarial rate 17%) (HR 2.54, 95% CI 1.07–6.04, p = 0.034). Conclusions: This study examined patterns of recurrence after postoperative radiotherapy and its implications for radiation dose, radiation field size, and treatment sequence. Local control was high after total resection. Radiation field size appeared adequate given the low incidence of marginal recurrences. Patients with cerebellar metastases showed an increased risk of LMD, underscoring the need for preventive measures, particularly preoperative SRT.

Inhoud – 1 Ontwikkeling van de radiotherapie – 2 Radiobiologie – 3 Rol van de radiotherapie – 4 Vormen van radiotherapie – 5 Route van de patiënt over de afdeling – 6 Kwaliteitszorg – 7 Het radiotherapieteam – De ontdekking van de röntgen- en gammastraling in 1895 leidde in de twintigste eeuw tot de ontwikkeling van de radiotherapie. Om straling effectief en verantwoord te kunnen toepassen als therapie bij verschillende aandoeningen, werd steeds meer kennis vergaard over de benodigde doses en de tolerantie van het omliggende weefsel. Zo werd de dosimetrie ontwikkeld en kwam steeds meer apparatuur beschikbaar om aan de uiteenlopende eisen te voldoen. De afgelopen twintig jaar heeft de ontwikkeling van computerhardware en -software grote invloed gehad op de praktische toepassing van radiotherapie. De radiobiologie heeft veel van de in de praktijk opgebouwde kennis nader verklaard en werd zo een bron voor verdere ontwikkelingen. Radiotherapie wordt uitgevoerd via uitwendige bestraling (megavoltstraling, orthovoltstraling, elektronenstraling of protonenstraling) of inwendige bestraling (brachytherapie). De behandeling van de patiënt wordt uitgevoerd door een multidisciplinair radiotherapieteam. Daarbij worden verschillende stappen gevolgd, van het informeren van de patiënt, het uitvoeren van diverse onderzoeken – vaak met behulp van MRI- of PET-CT-scans –, het bepalen van de juiste positionering en het vervaardigen van fixatiemiddelen tot het maken van een bestralingsplan en het uitvoeren daarvan. Kwaliteitszorg heeft daarbij voortdurend de aandacht.

Background and purpose: Previous research among Dutch radiotherapy centres (RTCs) showed that 69% of innovations was simultaneously implemented in 7/19 centres, with a success rate of 51%. However, no structure to share lessons learned about the implementation process existed. Therefore, a national Taskforce Implementation (TTI) was raised to stimulate efficient implementation of innovations. The aim of the current study was to develop and pilot-evaluate a website for facilitating mutual learning on implementation issues. Material and methods: First, we made an inventory in all Dutch RTCs on their 10 most valuable innovations between 2019 and 2022. In-depth interviews, structured according to the Consolidated Framework for Implementation Research, were performed on the four most mentioned topics. A website was built, and pilot evaluated 1 year after the launch, using a qualitative survey amongst the TTI members. Results: In 13/18 centres, 19 interviews were conducted on 1) automation, 2) patient participation, 3) adaptive radiotherapy 4) surface guided radiotherapy and tracking. Most innovations (13/16) were implemented with a delay, with many comparable challenges: e.g. shortage of personnel (7/16) and prioritization of projects (9/16). The website allows users to upload and search for projects, including implementation experiences. After 1 year, 14 projects were uploaded. The qualitative evaluation was largely positive with room for improvement, i.e.75 % would recommend the website to others. Conclusion: This study showed that RTCs experience comparable challenges when implementing innovations, thereby underlining the need for a platform to share implementation-lessons learned. The first concept of this platform was evaluated positively.

From the US-SEER cancer registries, it appeared that radiation therapy (RT), administered between 1973 and 1982, resulted in an increased mortality rate up to 10-20 years after treatment for left-sided breast cancer (BC) patients [1].Furthermore, Darby et al. reported that major cardiac events (MCE) incidence rates increased linearly with mean heart dose (MHD) by 7.4% relative per Gray [2].Similar results were found in two Dutch and one Danish study [3][4][5].Thereafter, MHD is used as a normative planning parameter in BC-RT in daily practice as well as in studies [6][7][8].Recently, though, the presence of a dose-effect relationship was not confirmed [9,10].Therefore, we decided to evaluate whether a linear association between MHD and MCE-incidence rates still applies and noted:

PURPOSE:The aim of the current study is to compare the dosimetry of 3 radiation therapy (RT) techniques used in the EORTC 22922/10925 trial for irradiating the internal mammary (IM) and medial supraclavicular nodes (MS) using a treatment planning system available nowadays for dose calculation. METHODS:We performed a retrospective dosimetry analysis of anonymised data; thus, ethics approval was not required. Ten cases of left-sided breast were randomly selected for RT planning to a total dose of 50 Gy in 25 fractions. The treatment planning was done according to the trial's protocol and under the supervision of the EORTC trial's coordinators. Doses to planning target volumes (PTV) and to organs at risk (OARs) are reported. Data is presented in descriptive statistics. RESULTS:A total of 10 cases and 40 treatment plans (4 plans per case: standard-plan A, modified standard-plan B, individualised-plan C and breast-only-plan D). For all planning techniques, the mean dose to the PTV of the left breast (plan A-D) and the PTV-MS (plan A-C) exceeded 95% of the prescribed dose (>47.5 Gy). The individualised technique (plan C) had a lower coverage for PTV-IM, with a mean of 87% of the prescribed dose compared to ∼102% for plans A and B. The dose to OARs varied between techniques, with the mean heart dose being higher in the standard and modified standard techniques (18.3 and 16.6 Gy, respectively) compared to the individualised technique (9.5 Gy). CONCLUSIONS:The 3 RT techniques used in the trial varied in target coverage and OARs dose. Our results may help to understand the observed larger absolute benefit of individualised IM-MS treatment planning in terms of breast cancer outcomes.

Purpose: The aim of this study is to evaluate the cosmetic outcome among early stage breast cancer patients who underwent accelerated partial breast irradiation with either intraoperative electron radiotherapy (IOERT) or photon external beam radiotherapy (EB-APBI). Materials and methods: This prospective multicenter cohort study enrolled women aged 60 years and older who underwent breast-conserving therapy. Following breast-conserving surgery, patients were treated with either IOERT or EB-APBI. Cosmetic outcome was evaluated over a 5 year follow-up period using both subjective scoring by patients and physicians, as well as objective scoring using BCCT.core software. Differences between treatments over time were described with mixed model analyses. Results: A total of 241 patients treated with IOERT and 164 patients treated with EB-APBI were eligible for cosmetic analysis. In both groups, the majority of patients reported a satisfactory cosmetic outcome, with no significant differences between treatments over time (p = 0.538). This was also observed by physicians, with satisfactory outcomes ranging from 94 % (170/181) to 91 % (69/76) over time in the IOERT group and from 93 % (124/133) to 95 % (54/57) in the EB-APBI group (p = 0.579). BCCT.core analysis returned satisfactory cosmetic outcomes in 75 % (54/72) of the IOERT patients at 3 years and in 77 % (20/26) at 5 years. These numbers were 86 % (72/84) and 90 % (36/40) for the EB-APBI patients, with no significant differences between treatment over time (p = 0.834). Conclusion: Regarding the cosmetic results, IOERT and EB-APBI yield comparable and satisfactory outcomes over 5 years follow-up in the treatment of early stage breast cancer.

Introduction: Neurosurgical resection is the standard treatment for large brain metastases (BMs). Perioperative tumor spill is an important complication which is theorized to contribute to leptomeningeal disease (LMD). Postoperative stereotactic radiotherapy (SRT) is used to improve local control, but does not always prevent LMD. This study aims to identify patients at increased risk of developing LMD after postoperative SRT. Methods: We included 147 patients who underwent resection and SRT for BMs. Univariable and multivariable Cox regression analyses were used to assess associations of LMD with various patient characteristics. Results: Median survival after postoperative SRT was 14 months (IQR 6-30) with 3-year actuarial survival rate of 21%. LMD was diagnosed in 21/147 patients (14%; 3-year actuarial rate 26%). Patients with resected cerebellar metastases were more likely to develop LMD than those with cerebral metastases (HR 4.24, 95% CI 1.11-16.3, P = 0.035). Incidence of LMD for cerebellar metastases was 9/40 (23%; 3-year actuarial rate 46%) and 12/107 (11%; 3-year actuarial rate 17%) in cerebral metastases. Median survival after LMD diagnosis was 4 months. Conclusion: Patients with a resected cerebellar BM were at increased risk to develop LMD compared to patients with cerebral BMs. Survival after LMD was poor, highlighting the need for effective preventative strategies.

BACKGROUND:In the era of personalized medicine, individualized prognostic models with tumor characteristics are needed to inform patients about survival. Before clinical use, external validation of such models by an independent group is needed. An updated version of the graded prognostic assessment (GPA) estimates survival in patients with brain metastases (BMs) of non-small cell lung cancer (NSCLC). This is the first external validation of the updated Lung-molGPA in patients treated with stereotactic radiotherapy (SRT) for one or more BMs. MATERIALS AND METHODS:Patients treated with SRT for BMs from NSCLC adenocarcinoma were retrospectively included. GPA score was calculated for each patient based on six prognostic factors including age, Karnofsky Performance Status, number of BMs, extracranial metastases, EGFR/ALK status, and PD-L1 expression. Kaplan-Meier analysis evaluated survival probability. Impact of individual prognostic factors on survival was assessed by univariate and multivariate analyses using the Cox proportional hazard model. Predictive performance was evaluated using discrimination (C-statistic) and calibration (Brier test). RESULTS:The cohort (n = 241) was divided into four prognostic groups. Overall median survival was 15 months. Predicted and observed median survival were similar between the original and validation cohorts, apart from the most favorable prognostic group. With adequate C-statistics and Brier scores, the Lung-molGPA provided accurate survival predictions. CONCLUSION:The Lung-molGPA accurately predicted survival in our European population, except for an overestimation of survival in the small most favorable prognostic group. This prognostic model was externally validated and is therefore useful for counseling of patients with BMs of NSCLC adenocarcinoma.

Summary of recommendations.Tabled 1TopicRecommendationsPositioning•For most breast cancer treatments supine is the standard position. For patients with larger breasts or patients that require a higher degree of lung sparing, prone can be considered if the equipment and expertise are available.•Both arms up are considered more stable; one arm up may be considered for patients that cannot tolerate both arms up.•When using supine positioning, both flat and elevated board positions are acceptable provided collision risks are managed and the patient is appropriately stabilised.Immobilisation•There is insufficient evidence to support the adoption of any specific immobilisation device of the breast. The pro and cons of specific immobilisation devices must be weighed carefully and evaluated by the local department prior to clinical implementation.Setup•In the absence of surface guided imaging, the use of skin marking is required.•The available options for skin marking should be discussed taking into account long-term patient experience and patient preference.Position verification•Daily 2D-2D or 3D online position verification should be used where feasible.•2D online/offline position verification is appropriate with consideration of limitations.•Image matching should consider bony anatomy as well as soft tissue displacement/deformation.•SGRT should not replace standard image-guidance without local validation and particular caution to partial-breast/integrated-boost treatments. Open table in a new tab