Targeting serine/glycine metabolism improves radiotherapy response in non-small cell lung cancer.

BACKGROUND: Lung cancer is the most lethal cancer, and 85% of cases are classified as non-small cell lung cancer (NSCLC). Metabolic rewiring is a cancer hallmark that causes treatment resistance, and lacks insights into serine/glycine pathway adaptations upon radiotherapy. METHODS: We analyzed radiotherapy responses using mass-spectrometry-based metabolomics in NSCLC patient's plasma and cell lines. Efficacy of serine/glycine conversion inhibitor sertraline with radiotherapy was investigated by proliferation, clonogenic and spheroid assays, and in vivo using a serine/glycine dependent NSCLC mouse model by assessment of tumor growth, metabolite and cytokine levels, and immune signatures. RESULTS: Serine/glycine pathway metabolites were significantly consumed in response to radiotherapy in NSCLC patients and cell models. Combining sertraline with radiotherapy impaired NSCLC proliferation, clonogenicity and stem cell self-renewal capacity. In vivo, NSCLC tumor growth was reduced solely in the sertraline plus radiotherapy combination treatment group. Tumor weights linked to systemic serine/glycine pathway metabolite levels, and were inhibited in the combination therapy group. Interestingly, combination therapy reshaped the tumor microenvironment via cytokines associated with natural killer cells, supported by eradication of immune checkpoint galectin-1 and elevated granzyme B levels. CONCLUSION: Our findings highlight that targeting serine/glycine metabolism using sertraline restricts cancer cell recovery from radiotherapy and provides tumor control through immunomodulation in NSCLC.

Challenges and opportunities for proton therapy during pregnancy.

During pregnancy, the use of radiation therapy for cancer treatment is often considered impossible due to the assumed associated fetal risks. However, suboptimal treatment of pregnant cancer patients and unjustifiable delay in radiation therapy until after delivery can be harmful for both patient and child. In non-pregnant patients, proton-radiation therapy is increasingly administered because of its favorable dosimetric properties compared with photon-radiation therapy. Although data on the use of pencil beam scanning proton-radiation therapy during pregnancy are scarce, different case reports and dosimetric studies have indicated a more than 10-fold reduction in fetal radiation exposure compared with photon-radiation therapy. Nonetheless, the implementation of proton-radiation therapy during pregnancy requires complex fetal dosimetry for the neutron-dominated out-of-field radiation dose and faces a lack of clinical guidelines. Further exploration and standardization of proton-radiation therapy during pregnancy will be necessary to improve radiotherapeutic management of pregnant women with cancer and further reduce risks for their offspring.

Metastases-directed stereotactic body radiotherapy in combination with targeted therapy or immunotherapy: systematic review and consensus recommendations by the EORTC-ESTRO OligoCare consortium.

Stereotactic body radiotherapy (SBRT) for patients with metastatic cancer, especially when characterised by a low tumour burden (ie, oligometastatic disease), receiving targeted therapy or immunotherapy has become a frequently practised and guideline-supported treatment strategy. Despite the increasing use in routine clinical practice, there is little information on the safety of combining SBRT with modern targeted therapy or immunotherapy and a paucity of high-level evidence to guide clinical management. A systematic literature review was performed to identify the toxicity profiles of combined metastases-directed SBRT and targeted therapy or immunotherapy. These results served as the basis for an international Delphi consensus process among 28 interdisciplinary experts who are members of the European Society for Radiotherapy and Oncology (ESTRO) and European Organisation for Research and Treatment of Cancer (EORTC) OligoCare consortium. Consensus was sought about risk mitigation strategies of metastases-directed SBRT combined with targeted therapy or immunotherapy; a potential need for and length of interruption to targeted therapy or immunotherapy around SBRT delivery; and potential adaptations of radiation dose and fractionation. Results of this systematic review and consensus process compile the best available evidence for safe combination of metastases-directed SBRT and targeted therapy or immunotherapy for patients with metastatic or oligometastatic cancer and aim to guide today's clinical practice and the design of future clinical trials.

Hyperthermic Intrathoracic Chemotherapy (HITHOC) for Pleural Disseminated Thymoma: A Systematic Literature Review.

BACKGROUND: Optimal treatment for thymoma with pleural dissemination (TPD) remains unclear. Extended radical resection is the cornerstone for local treatment but the need for pleuro-pneumonectomy is debatable. Cytoreductive surgery with intraoperative hyperthermic intrathoracic chemotherapy (HITHOC) provides an alternative strategy to reduce tumor load and prevent pleural recurrence. OBJECTIVE: The aim of this review was to provide an overview of current literature regarding HITHOC for TPD. METHODS: A systematic literature review (PRISMA) was performed in the EMBASE, MEDLINE, Cochrane and Web of Science databases, resulting in 154 papers selected for screening (PROSPERO: CRD42020208242). Title, abstract, and full-text screening resulted in 13 papers subjected to structured data extraction and methodological quality assessment. One additional case from our department was included. Inclusion criteria were original research reporting on patients diagnosed with TPD; oncological outcome reporting; intraoperative HITHOC; and papers written in English, Dutch or German. Methodological quality was assessed using the Risk-of-Bias (RoB)-2 Tool and the Newcastle-Ottawa scale. RESULTS: HITHOC for TPD was reported in 171 cases. HITHOC-related mortality was absent and morbidity was reported in three cases. Intrathoracic perfusion of a platinum-derivative, often combined with other chemotherapeutic drugs at >40°C for 60 min or longer was always used. Post-HITHOC recurrence was reported in 37/120 cases (31%). In patients with a minimal 1-year follow-up, average time to recurrence was 68.5 months. CONCLUSION: Combining cytoreductive surgery and HITHOC is feasible and safe for TPD. The strong heterogeneity in the literature impedes proper outcome analysis. More research is needed to better understand the additional benefit of HITHOC in the TPD setting.

Comparison of prone and supine positioning for breast cancer radiotherapy using REQUITE data: dosimetry, acute and two years physician and patient-reported outcomes.

OBJECTIVE: Most patients receive whole breast radiotherapy in a supine position. However, two randomised trials showed lower acute toxicity in prone position. Furthermore, in most patients, prone positioning reduced doses to the organs at risk. To confirm these findings, we compared toxicity outcomes, photographic assessment, and dosimetry between both positions using REQUITE data. METHODS: REQUITE is an international multi-centre prospective observational study that recruited 2069 breast cancer patients receiving radiotherapy. Data on toxicity, health-related quality of life (HRQoL), and dosimetry were collected, as well as a photographic assessment. A matched case control analysis compared patients treated prone (n = 268) versus supine (n = 493). Exact matching was performed for the use of intensity-modulated radiotherapy, boost, lymph node irradiation, chemotherapy and fractionation, and the nearest neighbour for breast volume. Primary endpoints were dermatitis at the end of radiotherapy, and atrophy and cosmetic outcome by photographic assessment at two years. RESULTS: At the last treatment fraction, there was no significant difference in dermatitis (p = .28) or any HRQoL domain, but prone positioning increased the risk of breast oedema (p < .001). At 2 years, patients treated in prone position had less atrophy (p = .01), and higher body image (p < .001), and social functioning (p < .001) scores. The photographic assessment showed no difference in cosmesis at 2 years (p = .22). In prone position, mean heart dose (MHD) was significantly lower for left-sided patients (1.29 Gy vs 2.10 Gy, p < .001) and ipsilateral mean lung dose (MLD) was significantly lower for all patients (2.77 Gy vs 5.89 Gy, p < .001). CONCLUSIONS: Prone radiotherapy showed lower MLD and MHD compared to supine position, although the risk of developing breast oedema during radiotherapy was higher. At 2 years the photographic assessment showed no difference in the cosmetic outcome, but less atrophy was seen in prone-treated patients and this seems to have a positive influence on the HRQoL domain of body image.

Neurocognition in adults with intracranial tumors: does location really matter?

OBJECTIVE: As preservation of cognitive functioning increasingly becomes important in the light of ameliorated survival after intracranial tumor treatments, identification of eloquent brain areas would enable optimization of these treatments. METHODS: This cohort study enrolled adult intracranial tumor patients who received neuropsychological assessments pre-irradiation, estimating processing speed, verbal fluency and memory. Anatomical magnetic resonance imaging scans were used for multivariate voxel-wise lesion-symptom predictions of the test scores (corrected for age, gender, educational level, histological subtype, surgery, and tumor volume). Potential effects of histological and molecular subtype and corresponding WHO grades on the risk of cognitive impairment were investigated using Chi square tests. P-values were adjusted for multiple comparisons (p < .001 and p < .05 for voxel- and cluster-level, resp.). RESULTS: A cohort of 179 intracranial tumor patients was included [aged 19-85 years, median age (SD) = 58.46 (14.62), 50% females]. In this cohort, test-specific impairment was detected in 20-30% of patients. Higher WHO grade was associated with lower processing speed, cognitive flexibility and delayed memory in gliomas, while no acute surgery-effects were found. No grading, nor surgery effects were found in meningiomas. The voxel-wise analyses showed that tumor locations in left temporal areas and right temporo-parietal areas were related to verbal memory and processing speed, respectively. INTERPRETATION: Patients with intracranial tumors affecting the left temporal areas and right temporo-parietal areas might specifically be vulnerable for lower verbal memory and processing speed. These specific patients at-risk might benefit from early-stage interventions. Furthermore, based on future validation studies, imaging-informed surgical and radiotherapy planning could further be improved.

Stroke rate after external fractionated radiotherapy for benign meningioma.

PURPOSE: Patients with a benign meningioma often have a long survival following the treatment of their meningioma. Since radiotherapy is frequently part of the treatment, long-term side effects are of considerable concern. A controversial long-term side effect of radiotherapy is stroke. Due to its severity, it is important to know the frequency of this side effect. The aim of this study was to assess the stroke incidence and risk factors among patients receiving radiotherapy for their benign meningioma. METHODS: We performed a retrospective database study of patients who underwent primary or adjuvant radiotherapy for their benign meningioma at University Hospitals Leuven from January 2003 to December 2017. RESULTS: We included 169 patients with a median age of 51 years (range 22-84). Every patient received fractionated radiotherapy using photons with a median dose of 56 Gy (range 54-56) in fractions of 2 Gy (range 1.8-2). The median follow-up was 5.3 years (range 0.1-14). The cumulative stroke incidence function showed an incidence of 11.6% after 9 years of follow-up, translating to a stroke incidence per year of 1.29%. We found two significant risk factors for stroke: medically treated arterial hypertension (p = 0.005) and history of previous stroke or transient ischemic attack (p < 0.001). 5-year local control and overall survival rates were respectively 97.4% and 91.2%. Other late grade III/IV toxicities occurred in 16.0% (27/169) of patients. CONCLUSION: Our study shows a higher incidence of stroke in patients who received radiotherapy for their benign meningioma compared to the general population.

Stereotactic robotic body radiotherapy for patients with oligorecurrent pulmonary metastases.

BACKGROUND: Our aim is to report treatment efficacy and toxicity of patients treated by robotic (Cyberknife®) stereotactic body radiotherapy (SBRT) for oligorecurrent lung metastases (ORLM). Additionally we wanted to evaluate influence of tumor, patient and treatment related parameters on local control (LC), lung and distant progression free- (lung PFS/Di-PFS) and overall survival (OS). METHODS: Consecutive patients with up to 5 ORLM (confirmed by FDG PET/CT) were included in this study. Intended dose was 60Gy in 3 fractions (prescribed to the 80% isodose volume). Patients were followed at regular intervals and tumor control and toxicity was prospectively scored. Tumor, patient and treatment data were analysed using competing risk- and Cox regression. RESULTS: Between May 2010 and March 2016, 104 patients with 132 lesions were irradiated from primary lung carcinoma (47%), gastro-intestinal (34%) and mixed primary histologies (19%). The mean tumor volume was 7.9 cc. After a median follow up of 22 months, the 1, 2 and 3 year LC rate (per lesion) was 89.3, 80.0 and 77.8% respectively. The corresponding (per patient) 1, 2 and 3 years lung PFS were 66.3, 50.0, 42.6%, Di-PFS were 80.5, 64.4, 60.6% and OS rates were 92.2, 80.9 and 72.0% respectively. On univariable analysis, gastro-intestinal (GI) as primary tumor site showed a significant superior local control versus the other primary tumor sites. For OS, significant variables were primary histology and primary tumor site with a superior OS for patients with metastases of primary GI origin. LC was significantly affected by the tumor volume, physical and biologically effective dose coverage. Significant variables in multivariable analysis were BED prescription dose for LC and GI as primary site for OS. The vast majority of patients developed no toxicity or grade 1 acute and late toxicity. Acute and late grade 3 radiation pneumonitis (RP) was observed in 1 and 2 patients respectively. One patient with a centrally located lesion developed grade 4 RP and died due to possible RT-induced pulmonary hemorrhage. CONCLUSIONS: SBRT is a highly effective local therapy for oligorecurrent lung metastases and could achieve long term survival in patients with favourable prognostic features.

Radiotherapy in combination with immune checkpoint inhibitors.

PURPOSE OF REVIEW: The immunomodulatory effects of ionizing radiation have long been recognized; however, so far these have not been fully exploited in clinical practice. We review the rationale to combine radiation with immune checkpoint inhibitors, which are used in standard practice. RECENT FINDINGS: Preclinical research suggests a synergy between radiotherapy and these immune checkpoint inhibitors. Whether or not this benefit translates into a clinical benefit is currently subject of ongoing research. SUMMARY: It is highly rational to combine radiation with immune therapy as in preclinical models and in proof of concept trials in humans it clearly can increase the antitumor immunity when given together with other immune interventions.

Preoperative risk factors for prolonged postoperative ileus after colorectal resection.

PURPOSE: Prolonged postoperative ileus (PPOI) after colorectal resection significantly impacts patients' recovery and hospital stay. Because treatment options for PPOI are limited, it is necessary to focus on prevention strategies. The aim of this study is to investigate risk factors associated with PPOI in patients undergoing colorectal surgery. METHODS: Data from all consecutive patients who underwent colorectal resection in our department were retrospectively analyzed from a prospective database over a 9-month period. PPOI was defined as the necessity to insert a nasogastric tube in a patient who experienced nausea and two episodes of vomiting with absence of bowel function. Multivariable analysis was performed considering a prespecified list of 16 potential preoperative risk factors. RESULTS: A total of 523 patients (mean age 59 years; 52.2% males) were included, and 83 patients (15.9%) developed PPOI. Statistically significant independent predictors of PPOI were male sex (OR 2.07; P = 0.0034), open resection (OR 4.47; P < 0.0001), conversion to laparotomy (OR 4.83; P = 0.0015), splenic flexure mobilization (OR 1.72; P = 0.063), and rectal resection (OR 2.72; P = 0.0047). Discriminative ability of this prediction model was 0.72. CONCLUSIONS: Therapeutic strategies aimed to prevent PPOI after colorectal resection should focus on patients with increased risk. Patients and medical staff can be informed of the higher PPOI risk, so that early treatment can be started.

Clinical and dosimetric evaluation of RapidArc versus standard sliding window IMRT in the treatment of head and neck cancer.

BACKGROUND: Several planning studies have already proven the substantial dosimetric advantages of RapidArc (RA) over standard intensity-modulated radiotherapy. We retrospectively compared RapidArc and standard sliding window IMRT (swIMRT) in locally advanced head and neck cancer, looking both at dosimetrics as well as toxicity and outcome. METHODS: CT datasets of 78 patients treated with swIMRT and 79 patients treated with RA were included. To compare the resulting dose distributions, the dose-volume parameters were evaluated for the planning target volumes (PTVs), clinical target volumes (CTVs), and organs at risk (OARs), and the number of MU were calculated. Acute toxicity was assessed by the Common Toxicity Criteria version 3.0. RESULTS: PTV coverage with the 95% isodose was slightly better for RA. Dose distribution has proven to be significantly more homogenous with RA and led to a reduction of 62% in MU with better OAR sparing. As for toxicity, more grade 3 mucositis and dysphagia was observed for swIMRT, though we observed more grade 3 dermatitis for RA. CONCLUSION: In our retrospective analysis, RA had better target coverage and better sparing of the OAR. Overall, the grade of acute toxicity was lower for RA than for swIMRT for the same types of tumor locations, except for the grade of dermatitis.

Are offline ART decisions for NSCLC impacted by the type of dose calculation algorithm?

Introduction: Decisions for plan-adaptations may be impacted by a transitioning from one dose-calculation algorithm to another. This study examines the impact on dosimetric-triggered offline adaptation in LA-NSCLC in the context of a transition from superposition/convolution dose calculation algorithm (Type-B) to linear Boltzmann equation solver dose calculation algorithms (Type-C). Materials & Methods: Two dosimetric-triggered offline adaptive treatment workflows are compared in a retrospective planning study on 30 LA-NSCLC patients. One workflow uses a Type-B dose calculation algorithm and the other uses Type-C. Treatment plans were re-calculated on the anatomy of a mid-treatment synthetic-CT utilizing the same algorithm utilized for pre-treatment planning. Assessment for plan-adaptation was evaluated through a decision model based on target coverage and OAR constraint violation. The impact of algorithm during treatment planning was controlled for by recalculating the Type-B plan with Type-C. Results: In the Type-B approach, 13 patients required adaptation due to OAR-constraint violations, while 15 patients required adaptation in the Type-C approach. For 8 out of 30 cases, the decision to adapt was opposite in both approaches. None of the patients in our dataset encountered CTV-target underdosage that necessitated plan-adaptation. Upon recalculating the Type-B approach with the Type-C algorithm, it was shown that 10 of the original Type-B plans revealed clinically relevant dose reductions (≥3%) on the CTV in their original plans. This re-calculation identified 21 plans in total that required ART. Discussion: In our study, nearly one-third of the cases would have a different decision for plan-adaption when utilizing Type-C instead of Type-B. There was no substantial increase in the total number of plan-adaptations for LA-NSCLC. However, Type-C is more sensitive to altered anatomy during treatment compared to Type-B. Recalculating Type-B plans with the Type-C algorithm revealed an increase from 13 to 21 cases triggering ART.

A prospective randomized study comparing two frameless immobilization systems for cranial stereotactic radiotherapy.

Introduction: The Dual Shell Encompass Fibreplast™ System (DS-Encompass) by CQ Medical™ is validated for frameless immobilization in stereotactic brain radiotherapy. An alternative mask model has been proposed with the rear shell replaced by a Moldcare® cushion (M-Encompass). To validate the use of this model in our cranial stereotactic workflow method including HyperArc™, we performed a prospective randomized study comparing inter-and intrafractional motion and patients comfort between both masks. Materials & Methods: A prospective randomized study between DS-Encompass and M-Encompass was conducted involving 60 participants. Stratification between DS-Encompass and M-Encompass was carried out based on the fractionation scheme. Treatment plans were created with HyperArc™. During treatment, surface guidance was used for patient positioning and monitoring. A pre-treatment cone-beam CT (CBCT) was acquired to correct interfractional motion and a post-treatment CBCT was acquired to quantify the intrafractional motion. Patients reported comfort was analyzed with a Likert-scale at the end of the treatment. Unpaired t-tests were conducted to determine the level of significance. Results: No significant difference in interfractional translations is present. A significant difference is revealed in roll-axis rotation, where DS-Encompass allows for smaller deviations. Since interfractional motion can be corrected through daily CBCT-scans and 6D-couch corrections, they are clinically irrelevant. Intrafractional motion does not differ significantly and remains below 0.5 mm and 0.5° for both systems. There is no statistical difference in patient-reported comfort. Conclusion: We conclude that Encompass with Moldcare offers a safe alternative to Duall Shell Encompass for non-coplanar stereotactic brain radiotherapy. There is no significant difference in intrafractional motion nor difference in comfort levels.

Brain network topology and its cognitive impact in adult glioma survivors.

Structural brain network topology can be altered in case of a brain tumor, due to both the tumor itself and its treatment. In this study, we explored the role of structural whole-brain and nodal network metrics and their association with cognitive functioning. Fifty WHO grade 2-3 adult glioma survivors (> 1-year post-therapy) and 50 matched healthy controls underwent a cognitive assessment, covering six cognitive domains. Raw cognitive assessment scores were transformed into w-scores, corrected for age and education. Furthermore, based on multi-shell diffusion-weighted MRI, whole-brain tractography was performed to create weighted graphs and to estimate whole-brain and nodal graph metrics. Hubs were defined based on nodal strength, betweenness centrality, clustering coefficient and shortest path length in healthy controls. Significant differences in these metrics between patients and controls were tested for the hub nodes (i.e. n = 12) and non-hub nodes (i.e. n = 30) in two mixed-design ANOVAs. Group differences in whole-brain graph measures were explored using Mann-Whitney U tests. Graph metrics that significantly differed were ultimately correlated with the cognitive domain-specific w-scores. Bonferroni correction was applied to correct for multiple testing. In survivors, the bilateral putamen were significantly less frequently observed as a hub (pbonf < 0.001). These nodes' assortativity values were positively correlated with attention (r(90) > 0.573, pbonf < 0.001), and proxy IQ (r(90) > 0.794, pbonf < 0.001). Attention and proxy IQ were significantly more often correlated with assortativity of hubs compared to non-hubs (pbonf < 0.001). Finally, the whole-brain graph measures of clustering coefficient (r = 0.685), global (r = 0.570) and local efficiency (r = 0.500) only correlated with proxy IQ (pbonf < 0.001). This study demonstrated potential reorganization of hubs in glioma survivors. Assortativity of these hubs was specifically associated with cognitive functioning, which could be important to consider in future modeling of cognitive outcomes and risk classification in glioma survivors.

Patient-reported outcomes after personalised dose-escalation for stage II-III non-small-cell lung cancer patients: Results from the randomised ARTFORCE PET-Boost trial.

BACKGROUND AND PURPOSE: The ultimate challenge in dose-escalation trials lies in finding the balance between benefit and toxicity. We examined patient-reported outcomes (PROs), including health-related quality of life (HRQoL) in patients with locally advanced non-small cell lung cancer (LA-NSCLC), treated with dose-escalated radiotherapy. MATERIALS AND METHODS: The international, randomised, phase 2 ARTFORCE PET-Boost study (NCT01024829) aimed to improve 1-year freedom from local failure rates in patients with stage II-III NSCLC, with a ≥ 4 cm primary tumour. Treatment consisted of an individualised, escalated fraction dose, either to the primary tumour as a whole or to its most FDG-avid subvolume (24 x 3.0-5.4 Gy). Patients received sequential or concurrent chemoradiotherapy, or radiotherapy only. Patients were asked to complete the EORTC QLQ-C30, QLQ-LC13, and the EuroQol-5D at eight timepoints. We assessed the effect of dose-escalation on C30 sum score through mixed-modelling and evaluated clinically meaningful changes for all outcomes. RESULTS: Between Apr-2010 and Sep-2017, 107 patients were randomised; 102 were included in the current analysis. Compliance rates: baseline 86.3%, 3-months 85.3%, 12-months 80.3%; lowest during radiation treatment 35.0%. A linear mixed-effect (LME) model revealed no significant change in overall HRQoL over time, and no significant difference between the two treatment groups. Physical functioning showed a gradual decline in both groups during treatment and at 18-months follow-up, while clinically meaningful worsening of dyspnoea was seen mainly at 3- and 6-months. CONCLUSION: In patients with LA-NSCLC treated with two dose-escalation strategies, the average patient-reported HRQoL remained stable in both groups, despite frequent patient-reported symptoms, including dyspnoea, dysphagia, and fatigue.

Coverage with evidence development program on stereotactic body radiotherapy in Belgium (2013-2019): a nationwide registry-based prospective study.

Background: Although stereotactic body radiotherapy (SBRT) was progressively adopted in clinical practice in Belgium, a reimbursement request in 2011 was not granted because of remaining clinical and economic uncertainty. A coverage with evidence development (CED) program on SBRT started in 2013, with the aim to assess clinical and technical patterns-of-care in Belgium and monitor survival per indication, in view of supporting inclusion in the reimbursement system. Methods: The Belgian National Institute for Health and Disability Insurance (NIHDI) initiated this prospective observational registry. Participating departments, using SBRT in clinical practice, signed the 'NIHDI convention'. Eligible patients had a primary tumour (PT) or oligometastatic disease (OMD). Patient, tumour, and treatment characteristics were collected through an online module of the Belgian Cancer Registry, prerequisite for financing. Five-year overall survival (5YOS) and 30- and 90-days mortality were primary outcomes, derived from vital status information. Findings: Between 10/2013 and 12/2019, 20 of the 24 accredited radiotherapy departments participated, 6 were academic. Registered cases per department ranged from 21 to 867. Of 5675 registrations analysed, the majority had good performance status and limited number of lesions. Enrolment of PTs remained stable over time, OMDs almost doubled. Peripheral lung lesions dominated in PTs as in OMDs. Other metastases were (para)spinal, 'non-standard' and hepatic. Thirty- and 90-days mortalities remained below 0.5% [95% CI 0.3%-0.8%] respectively 2.1% [95% CI 1.6%-2.7%]. 5YOS varied by indication, primary prostate patients performing best (85%, 95% CI [76%, 96%]), those with liver metastases worst (19%, 95% CI [15%, 24%]). Better OS was observed in academic departments, department size did not significantly impact survival. OMD survival was better in 2018-19. Interpretation: CED can be used to define patterns-of-care and real-life outcome of innovative radiotherapy. As the observed survival for different indications was in line with outcome in emerging literature, SBRT was included in the Belgian reimbursement system as of January 2020. Funding: NIHDI financed participating departments per registered case.

Long-term neurocognitive, psychosocial, and physical outcomes after prenatal exposure to radiotherapy: a multicentre cohort study of the International Network on Cancer, Infertility, and Pregnancy.

BACKGROUND: The main data available on the safety of radiation during pregnancy originate from animal studies and from studies of survivors of atomic or nuclear disasters. The effect of radiotherapy to treat maternal cancer on fetal development is uncertain. This report presents a unique cohort and aims to determine the long-term neurocognitive, psychosocial and physical outcomes of offspring of mothers treated with radiotherapy during pregnancy. METHODS: In this international, multicentre, mixed retrospective-prospective cohort study, we recruited participants between Aug 5, 2006, and Aug 24, 2023, aged between 1·5 and 46 years, at three referral centres in Belgium, the Netherlands, and the USA. Participants were eligible if they were born from mothers treated with radiotherapy during pregnancy. Fetal radiation doses were obtained from medical records and participants were followed up at predefined ages (1·5, 3, 6, 9, 12, 15, and 18 years) and 5-yearly in adulthood, based on age at enrolment, using a neurocognitive test battery (measuring intelligence, attention, and memory), parent-reported executive function and psychosocial questionnaires, and a medical assessment. Results were compared with test-specific normative data. Linear regression models investigated associations between radiotherapy factors (fetal radiation dose, gestational age at the start and end of radiotherapy, and radiotherapy duration) and outcomes. FINDINGS: 68 maternal cases of radiotherapy during pregnancy were registered by the three participating centres, of which 61 resulted in a livebirth and were therefore eligible to participate in the child follow-up study. After excluding those who did not give consent, 43 participants born from 42 mothers treated with radiotherapy during pregnancy were included in the study (median age at first assessment 3 years [IQR 2-11]; median age at last assessment 12 years [9-18]; median number of assessments two [1-4]). 18 (42%) of the included participants were female and 25 (58%) male, and 37 (86%) were of White ethnicity. Mean neurocognitive outcomes of the entire cohort were within normal ranges. No associations were found with fetal radiation dose or timing of radiotherapy during pregnancy. Six (16%) of 38 participants with neurocognitive outcomes scored lower than one SD on at least one neurocognitive outcome, three (7%) reported chronic medical conditions (spasmophilia, spastic diplegia, and IgG deficiency), and three (7%) were diagnosed with attention-deficit hyperactivity disorder (of whom two scored lower on attention). Of ten (23%) participants with lower neurocognitive score(s), a chronic medical condition, or attention-deficit hyperactivity disorder, eight were born preterm. The remaining 33 (77%) participants showed no neurocognitive, psychosocial, or chronic physical problems. INTERPRETATION: We show on average normal neurocognitive, psychosocial, and physical outcomes after prenatal exposure to radiotherapy. Differences in outcomes could not be explained by exposure to radiotherapy during pregnancy. These results suggest that extra-abdomino-pelvic radiotherapy exposure during pregnancy in general does not adversely affect outcomes of liveborn children. Further research with a larger sample is necessary to confirm these findings. FUNDING: Kom Op Tegen Kanker, KWF Kankerbestrijding, Stichting Tegen Kanker, Research Foundation Flanders.

Optimising inter-patient image registration for image-based data mining in breast radiotherapy.

Background and purpose: Image-based data mining (IBDM) requires spatial normalisation to reference anatomy, which is challenging in breast radiotherapy due to variations in the treatment position, breast shape and volume. We aim to optimise spatial normalisation for breast IBDM. Materials and methods: Data from 996 patients treated with radiotherapy for early-stage breast cancer, recruited in the REQUITE study, were included. Patients were treated supine (n = 811), with either bilateral or ipsilateral arm(s) raised (551/260, respectively) or in prone position (n = 185). Four deformable image registration (DIR) configurations for extrathoracic spatial normalisation were tested. We selected the best-performing DIR configuration and further investigated two pathways: i) registering prone/supine cohorts independently and ii) registering all patients to a supine reference. The impact of arm positioning in the supine cohort was quantified. DIR accuracy was estimated using Normalised Cross Correlation (NCC), Dice Similarity Coefficient (DSC), mean Distance to Agreement (MDA), 95 % Hausdorff Distance (95 %HD), and inter-patient landmark registration uncertainty (ILRU). Results: DIR using B-spline and normalised mutual information (NMI) performed the best across all evaluation metrics. Supine-supine registrations yielded highest accuracy (0.98 ± 0.01, 0.91 ± 0.04, 0.23 ± 0.19 cm, 1.17 ± 1.18 cm, 0.51 ± 0.26 cm for NCC, DSC, MDA, 95 %HD, and ILRU), followed by prone-prone and supine-prone registrations. Arm positioning had no significant impact on registration performance. For the best DIR strategy, uncertainty of 0.44 and 0.81 cm in the breast and shoulder regions was found. Conclusions: B-spline algorithm using NMI and registered supine and prone cohorts independently provides the most optimal spatial normalisation strategy for breast IBDM.