Pembrolizumab or placebo with chemoradiotherapy followed by pembrolizumab or placebo for newly diagnosed, high-risk, locally advanced cervical cancer (ENGOT-cx11/GOG-3047/KEYNOTE-A18): overall survival results from a randomised, double-blind, placebo-controlled, phase 3 trial.

BACKGROUND: At the first interim analysis of the phase 3 ENGOT-cx11/GOG-3047/KEYNOTE-A18 study, the addition of pembrolizumab to chemoradiotherapy provided a statistically significant and clinically meaningful improvement in progression-free survival in patients with locally advanced cervical cancer. We report the overall survival results from the second interim analysis of this study. METHODS: Eligible patients with newly diagnosed, high-risk (FIGO 2014 stage IB2-IIB with node-positive disease or stage III-IVA regardless of nodal status), locally advanced, histologically confirmed, squamous cell carcinoma, adenocarcinoma, or adenosquamous cervical cancer were randomly assigned 1:1 to receive five cycles of pembrolizumab (200 mg) or placebo every 3 weeks with concurrent chemoradiotherapy, followed by 15 cycles of pembrolizumab (400 mg) or placebo every 6 weeks. Pembrolizumab or placebo and cisplatin were administered intravenously. Patients were stratified at randomisation by planned external beam radiotherapy type (intensity-modulated radiotherapy [IMRT] or volumetric-modulated arc therapy [VMAT] vs non-IMRT or non-VMAT), cervical cancer stage at screening (FIGO 2014 stage IB2-IIB node positive vs III-IVA), and planned total radiotherapy (external beam radiotherapy plus brachytherapy) dose (<70 Gy vs ≥70 Gy [equivalent dose of 2 Gy]). Primary endpoints were progression-free survival per RECIST 1.1 by investigator or by histopathological confirmation of suspected disease progression and overall survival defined as the time from randomisation to death due to any cause. Safety was a secondary endpoint. FINDINGS: Between June 9, 2020, and Dec 15, 2022, 1060 patients at 176 sites in 30 countries across Asia, Australia, Europe, North America, and South America were randomly assigned to treatment, with 529 patients in the pembrolizumab-chemoradiotherapy group and 531 patients in the placebo-chemoradiotherapy group. At the protocol-specified second interim analysis (data cutoff Jan 8, 2024), median follow-up was 29·9 months (IQR 23·3-34·3). Median overall survival was not reached in either group; 36-month overall survival was 82·6% (95% CI 78·4-86·1) in the pembrolizumab-chemoradiotherapy group and 74·8% (70·1-78·8) in the placebo-chemoradiotherapy group. The hazard ratio for death was 0·67 (95% CI 0·50-0·90; p=0·0040), meeting the protocol-specified primary objective. 413 (78%) of 528 patients in the pembrolizumab-chemoradiotherapy group and 371 (70%) of 530 in the placebo-chemoradiotherapy group had a grade 3 or higher adverse event, with anaemia, white blood cell count decreased, and neutrophil count decreased being the most common adverse events. Potentially immune-mediated adverse events occurred in 206 (39%) of 528 patients in the pembrolizumab-chemoradiotherapy group and 90 (17%) of 530 patients in the placebo-chemoradiotherapy group. This study is registered with ClinicalTrials.gov, NCT04221945. INTERPRETATION: Pembrolizumab plus chemoradiotherapy significantly improved overall survival in patients with locally advanced cervical cancer These data, together with results from the first interim analysis, support this immuno-chemoradiotherapy strategy as a new standard of care for this population. FUNDING: Merck Sharp & Dohme, a subsidiary of Merck & Co.

Pembrolizumab or placebo with chemoradiotherapy followed by pembrolizumab or placebo for newly diagnosed, high-risk, locally advanced cervical cancer (ENGOT-cx11/GOG-3047/KEYNOTE-A18): a randomised, double-blind, phase 3 clinical trial.

BACKGROUND: Pembrolizumab has shown efficacy in persistent, recurrent, or metastatic cervical cancer. The effect of chemoradiotherapy might be enhanced by immunotherapy. In this phase 3 trial, we assessed the efficacy and safety of adding pembrolizumab to chemoradiotherapy in locally advanced cervical cancer. METHODS: In this randomised, double-blind, placebo-controlled, phase 3 ENGOT-cx11/GOG-3047/KEYNOTE-A18 clinical trial, adults (age ≥18 years) at 176 medical centres in 30 countries with newly diagnosed, high-risk, locally advanced cervical cancer were randomly assigned (1:1) using an interactive voice-response system with integrated web response to receive 5 cycles of pembrolizumab (200 mg) or placebo every 3 weeks plus chemoradiotherapy, followed by 15 cycles of pembrolizumab (400 mg) or placebo every 6 weeks. Randomisation was stratified by planned external beam radiotherapy type (intensity-modulated radiotherapy or volumetric-modulated arc therapy vs non-intensity-modulated radiotherapy or non-volumetric-modulated arc therapy), cervical cancer stage at screening (International Federation of Gynecology and Obstetrics 2014 stage IB2-IIB node positive vs stage III-IVA), and planned total radiotherapy (external beam radiotherapy plus brachytherapy) dose (<70 Gy vs ≥70 Gy equivalent dose in 2 Gy fractions). Primary endpoints were progression-free survival per Response Evaluation Criteria in Solid Tumours version 1.1-by investigator or by histopathologic confirmation of suspected disease progression-and overall survival. Primary analysis was conducted in the intention-to-treat population, which included all randomly allocated participants. Safety was assessed in the as-treated population, which included all randomly allocated patients who received at least one dose of study treatment. This study is registered with ClinicalTrials.gov, NCT04221945, and is closed to new participants. FINDINGS: Between June 9, 2020, and Dec 15, 2022, 1060 participants were randomly assigned to treatment, with 529 assigned to the pembrolizumab-chemoradiotherapy group and 531 to the placebo-chemoradiotherapy group. At data cutoff (Jan 9, 2023), median follow-up was 17·9 months (IQR 11·3-22·3) in both treatment groups. Median progression-free survival was not reached in either group; rates at 24 months were 68% in the pembrolizumab-chemoradiotherapy group versus 57% in the placebo-chemoradiotherapy group. The hazard ratio (HR) for disease progression or death was 0·70 (95% CI 0·55-0·89, p=0·0020), meeting the protocol-specified primary objective. Overall survival at 24 months was 87% in the pembrolizumab-chemoradiotherapy group and 81% in the placebo-chemoradiotherapy group (information fraction 42·9%). The HR for death was 0·73 (0·49-1·07); these data have not crossed the boundary of statistical significance. Grade 3 or higher adverse event rates were 75% in the pembrolizumab-chemoradiotherapy group and 69% in the placebo-chemoradiotherapy group. INTERPRETATION: Pembrolizumab plus chemoradiotherapy significantly improved progression-free survival in patients with newly diagnosed, high-risk, locally advanced cervical cancer. FUNDING: Merck Sharp & Dohme, a subsidiary of Merck & Co (MSD).

Radical hysterectomy without adjuvant radiotherapy in patients with cervix carcinoma FIGO 2009 IB1, with or without positive Sedlis criteria.

INTRODUCTION: Lymphovascular space invasion (LVSI), deep (>1/3) stromal invasion (DSI) and large tumor size (>4 cm) have been identified as predictors for intermediate risk for recurrence according to Sedlis (at least two of the prior risk factors) in FIGO stage I cervical cancer. Adjuvant radiotherapy (RT) has been advocated in these patients(1,2), but remains controversial. METHOD: All consecutive patients (1997-2017) with cervical cancer FIGO (2009) stage IB1 (≤4 cm) were included. Primary aim was to analyze the recurrence rate. Secondary aim was to identify the risk factors for disease recurrence and survival. RESULTS: One-hundred-and-eighty-two patients were included in this retrospective study. Median follow-up was 13 years (range 8-17). Postoperatively, 21 patients received adjuvant therapy due to presence of positive lymph nodes, positive section margins or if a simple hysterectomy was performed (RT: n = 7, concomitant chemo radiotherapy (CCRT): n = 14). None of the patients with a combination of intermediate risk factors according to Sedlis (excluding patients >4 cm) underwent adjuvant RT/CCRT. Disease recurrence was observed in 19 patients (10%). Eleven patients died of disease. LVSI influenced progression-free survival (PFS) (HR 3.950, p = 0.0163) and disease-specific survival (DSS) (HR 4.637, p = 0.0497) significantly. However, the combination of LVSI, tumor size and DSI according to Sedlis did not influence overall survival (OS), DSS or PFS. CONCLUSION: Recurrence rate was low (10%), despite the fact that patients with intermediate risk factors according to Sedlis did not receive postoperative RT/CCRT. LVSI was the sole risk factor influencing PFS and DSS. Combinations of risk factors according to Sedlis did not predict worse outcome.

Assessment of stromal tumor infiltrating lymphocytes and immunohistochemical features in invasive micropapillary breast carcinoma with long-term outcomes.

PURPOSE: We studied the long-term outcomes of invasive micropapillary carcinoma (IMPCs) of the breast in relation to stromal tumor infiltrating lymphocytes (sTILs), prognostic biomarkers and clinicopathological features. METHODS: Stage I-III IMPCs treated with upfront surgery at our institution (January 2000 and December 2016) were included. Central pathology review was performed and sTILs (including zonal distribution and hot spot analysis) and tumor-associated plasma cells (TAPC) were evaluated. Expression of P53, BCL2, FOXP3, and WT1, which are variably linked to breast cancer prognosis, was measured by immunohistochemistry using tissue microarrays. Time-to-event endpoints were distant recurrence free interval (DRFI) and breast cancer-specific survival (BCSS). RESULTS: We included 111 patients of whom 59% were pure IMPCs. Standard clinicopathological features were comparable between pure and non-pure IMPCs. Overall, the mean sTILs level was 20% with higher proportion of sTILs present at the invasive front. There were no significant differences between pure- and non-pure IMPCs in sTILs levels, nor in the spatial distribution of the hot spot regions or in the distribution of TAPC. Higher sTILs correlated with worse DRFI (HR = 1.55; p = 0.0172) and BCSS (HR = 2.10; p < 0.001). CONCLUSIONS: Clinicopathological features, geographical distribution of sTILs and TAPC are similar between pure and non-pure IMPCs. Despite a high proportion of grade 3 tumors and lymph node involvement, we observed a low rate of distant recurrences and breast cancer-related death in this cohort of stage I-III IMPCs treated with primary surgery. Caution in interpretation of the observed prognostic correlations is required given the very low number of events, warranting validation in other cohorts.

A comparison of a brachytherapy and an external beam radiotherapy boost in breast-conserving therapy for breast cancer: local and any recurrences.

PURPOSE: Adding a tumour bed boost to whole-breast irradiation in breast-conserving therapy reduces local recurrence rates. The purpose of the present study was to investigate whether the boost technique influences the magnitude of the effect. METHODS: Patients treated with breast-conserving therapy for invasive breast cancer between 2000 and 2007 were included in the analysis. Three groups were considered according to the applied boost technique: electrons, brachytherapy or photons. The endpoints were local recurrence and any recurrence. Cox regression models were used and correction for the confounders in the association between boost technique and outcome was performed using multivariable models. RESULTS: 1879 tumours were included in the analysis. 1448 tumours (77.1%) were treated with an electron boost, 334 (17.8%) with a brachytherapy boost and 97 (5.2%) with a photon boost. Median follow-up was 13.1 years. The 10-year local recurrence rate was 2.2%. In multivariable analysis with correction for age, pathological Tumour or Node stage (pT, pN), chemotherapy and hormonal therapy, there was no significant difference between the three groups for the local recurrence risk (p = 0.89). 10-year any recurrence rate was 10.8%. In multivariable analysis with correction for age, pT, pN, resection margins, radiotherapy, year of diagnosis, chemotherapy and hormonal therapy, there was no significant difference between the brachytherapy group and the electron group or the photon group (p = 0.11 and p = 0.28, respectively). The photon group had more recurrences compared to the electron group (Hazard Ratio 1.81, 95% Confidence Interval 1.12; 2.92, p = 0.02). CONCLUSIONS: The local recurrence risk reduction of the tumour bed boost in breast-conserving therapy is not influenced by the applied boost technique.

Hemostatic radiotherapy: a narrative review of the literature.

BACKGROUND AND OBJECTIVE: In locally advanced cancer, bleeding is a common clinical presentation and radiotherapy (RT) provides a noninvasive, well-tolerated, cost-effective treatment. However, the choice for fractionation dose and schedule seem to merely depend on physician's preference rather than specific guidelines. We reviewed the available literature on palliative hemostatic RT for response rate (RR) and bleeding duration in relation with the given dose. METHODS: The PubMed database was used to search for articles, which were assessed by predetermined inclusion and exclusion criteria. A total of 54 articles, published over the last 20 years until December 2023 were analyzed for dose and/or fractionation regimen and their relation to the RR. KEY CONTENT AND FINDINGS: A variety of fractionation schedules are used for palliative symptom control, including hemostasis. Research focusing on hemostatic irradiation specifically and prospective studies are rare. Moreover, to our knowledge, there are no specific (prospective) studies ongoing. Both external beam radiotherapy (EBRT) and brachytherapy lead to bleeding control and daily or weekly hypofractionated irradiation is safe and effective for both high and low biological equivalent dose (BED) regimens. If feasible, based on patient condition, some studies favor higher BED regimens to obtain more durable tumor/higher bleeding response. Higher radiation dose for thoracic irradiation may be indicative for simultaneous presentation of obstruction and/or dysphagia. Brachytherapy may be used solely or in combination with EBRT or in the setting of re-irradiation. Short-course regimens are preferred in patients in with low performance index scores. For future studies, multivariate analysis, including BED, can be important to assess efficacy of different fractionation schedules for a variety of tumor etiologies. CONCLUSIONS: Hemostatic RT, both by EBRT and brachytherapy, appears to be a safe and effective palliative treatment that clinically and statistically significantly reduces bleeding in cancer patients. The available literature is limited regarding prospective and uniform evaluation of hemostatic RT, including fractionation schedules. BED seems to be indicative for a better RR for specific indications. Current evidence suggests that treatment decisions should be tailored according to the patients' condition, tumor etiology and other clinical symptoms. More (prospective) research focusing on hemostasis is necessary to develop clear guidelines.

Quantification of radiation-induced lung damage with CT scans: the possible benefit for radiogenomics.

BACKGROUND: Radiation-induced lung damage (RILD) is an important problem. Although physical parameters such as the mean lung dose are used in clinical practice, they are not suited for individualised radiotherapy. Objective, quantitative measurements of RILD on a continuous instead of on an ordinal, semi-quantitative, semi-subjective scale, are needed. METHODS: Hounsfield unit (HU) changes before versus three months post-radiotherapy were correlated per voxel with the radiotherapy dose in 95 lung cancer patients. Deformable registration was used to register pre- and post-CT scans and the density increase was quantified for various dose bins. The dose-response curve for increased HU was quantified using the slope of a linear regression (HU/Gy). The end-point for the toxicity analysis was dyspnoea ≥ grade 2. RESULTS: Radiation dose was linearly correlated with the change in HU (mean R(2) = 0.74 ± 0.28). No differences in HU/Gy between groups treated with stereotactic radiotherapy, conventional radiotherapy alone, sequential or concurrent chemo- radiotherapy were observed. In the whole patient group, 33/95 (34.7%) had dyspnoea ≥ G2. Of the 48 patients with a HU/Gy below the median, 16 (33.3%) developed dyspnoea ≥ G2, while in the 47 patients with a HU/Gy above the median, 17 (36.1%) had dyspnoea ≥ G2 (not significant). Individual patients showed a nearly 21-fold difference in radiosensitivity, with HU/Gy ranging from 0 to 10 HU/Gy. CONCLUSIONS: HU changes identify objectively the whole range of individual radiosensitivity on a continuous, quantitative scale. CT density changes may allow more robust and accurate radiogenomics studies.

Retrospective Analysis of the Clinical Presentation, Treatment and Outcome of Angiosarcoma in a Sarcoma Referral Center.

INTRODUCTION: Angiosarcoma (AS) is a rare subtype of soft tissue sarcoma. We performed a retrospective analysis of patient characteristics, treatments and prognostic factors in patients treated in a single sarcoma center. METHODS: We reviewed records of patients treated between 1987 and 2018, categorized in 7 different subtypes according to tissue of origin and underlying risk factors. The Kaplan-Meier method was used to estimate overall survival (OS); the Cox proportional hazards model was used to study prognostic variables. RESULTS: Among 134 patients, 30% had radiation-induced, 31% primary soft tissue, 24% cutaneous, 5% breast, 4% bone, 2% lymphedema-associated and 4% unknown primary AS. Key patient/disease characteristics varied between subgroups. The median OS was 22.0 months for the entire cohort, with 28.9% with a 5-year survival. Metastasis at diagnosis was seen in 23% of patients; 38% developed metachronous metastasis. Sixty-six (49%) patients received systemic therapy; common first-line treatments were doxorubicin (48%) and paclitaxel (39%), without a significant difference in OS between agents. Younger age, breast/radiation-induced AS, primary surgery and palliative chemotherapy were associated with better OS. Synchronous metastasis, soft tissue/unknown primary location correlated with poor survival. CONCLUSION: AS is a very heterogeneous sarcoma subtype, with substantial variability in clinical presentation and survival among patient subsets. Prognosis is poor, and there is no difference in outcome comparing the 2 most frequently used chemotherapy agents in the first line, paclitaxel and doxorubicin.

Curative, Organ-Sparing, Multimodal, Perioperative Treatment of a Young Patient with a Rectoanal Inflammatory Myofibroblastic Tumor.

INTRODUCTION: We report the case of a young female patient with a technically resectable, nonmetastatic, rectoanal, anaplastic lymphoma kinase gene (ALK)-translocated inflammatory myofibroblastic tumor (IMFT). CASE PRESENTATION: The patient was successfully treated preoperatively with the tyrosine kinase inhibitor (TKI) crizotinib, to downsize the primary tumor, followed by sphincter-sparing surgery, and adjuvant radiotherapy and crizotinib. She is now in follow-up with good sphincter function and with no evidence of active disease. CONCLUSION: Pre- and postoperative treatment administration of crizotinib can be given with curative intent to patients with locally advanced, nonmetastatic IMFTs to avoid mutilating surgery.

Germline HOXB13 mutations p.G84E and p.R217C do not confer an increased breast cancer risk.

In breast cancer, high levels of homeobox protein Hox-B13 (HOXB13) have been associated with disease progression of ER-positive breast cancer patients and resistance to tamoxifen treatment. Since HOXB13 p.G84E is a prostate cancer risk allele, we evaluated the association between HOXB13 germline mutations and breast cancer risk in a previous study consisting of 3,270 familial non-BRCA1/2 breast cancer cases and 2,327 controls from the Netherlands. Although both recurrent HOXB13 mutations p.G84E and p.R217C were not associated with breast cancer risk, the risk estimation for p.R217C was not very precise. To provide more conclusive evidence regarding the role of HOXB13 in breast cancer susceptibility, we here evaluated the association between HOXB13 mutations and increased breast cancer risk within 81 studies of the international Breast Cancer Association Consortium containing 68,521 invasive breast cancer patients and 54,865 controls. Both HOXB13 p.G84E and p.R217C did not associate with the development of breast cancer in European women, neither in the overall analysis (OR = 1.035, 95% CI = 0.859-1.246, P = 0.718 and OR = 0.798, 95% CI = 0.482-1.322, P = 0.381 respectively), nor in specific high-risk subgroups or breast cancer subtypes. Thus, although involved in breast cancer progression, HOXB13 is not a material breast cancer susceptibility gene.

Pooled Analysis of external-beam RADiotherapy parameters in phase II and phase III trials in radiochemotherapy in Anal Cancer (PARADAC).

PURPOSE: Concomitant external-beam radiochemotherapy (5-fluorouracil-mitomycin C) has become the standard of care in anal cancer since the '90s. A pooled analysis of individual patient data from 7 major trials was performed quantifying the effect of radiation therapy (RT)-related parameters on the outcome of patients with anal cancer. MATERIALS AND METHODS: Pooling databases from combined modality trials, the impact of RT parameters (total dose, gap duration, OTT: overall treatment time) on outcome including locoregional failure (LRF), 5-year progression free survival (PFS) and toxicities were investigated. Individual patient data were received for 10/13 identified published studies conducted from 1987 to 2008 (n = 3031). A Cox regression model was used (landmark = 3 months after RT for first follow-up). RESULTS: After data inspection indicating severe heterogeneity between trials, only 1343 patients from 7/10 studies received were analysed (the most recent ones, since 1994; median follow-up = 4.1 years). A higher overall 5-year LRF rate [22.8% (95% confidence interval [CI] 22.3-27.3%)] significantly correlated with longer OTT (p = 0.03), larger tumour size (p < 0.001) and male gender (p = 0.045). Although significant differences were not observed, subset analyses for LRF (dose range: 50.4-59 Gy) seemed to favour lower doses (p = 0.412), and when comparing a 2-week gap versus 3 (dose: 59.4 Gy), results suggested 3 weeks might be detrimental (p = 0.245). For a 2-week gap versus none (dose range: 55-59.4 Gy), no difference was observed (p = 0.89). Five-year PFS was 65.7% (95% CI: 62.8-68.5%). Higher PFS rates were observed in women (p < 0.001), smaller tumour sizes (p < 0.001) and shorter OTT (p = 0.025). Five-year overall survival [76.7% (95% CI: 73.9%-79.3%)] correlated positively with female gender (p < 0.001), small tumour size (p = 0.027) and short OTT (p = 0.026). Descriptive toxicity data are presented. CONCLUSION: For patients receiving concurrent external-beam doublet chemoradiation, a longer OTT seems detrimental to outcome. Further trials involving modern techniques may better define optimal OTT and total dose.

SIOPE - Brain tumor group consensus guideline on craniospinal target volume delineation for high-precision radiotherapy.

OBJECTIVE: To develop a consensus guideline for craniospinal target volume (TV) delineation in children and young adults participating in SIOPE studies in the era of high-precision radiotherapy. METHODS AND MATERIALS: During four consensus meetings (Cambridge, Essen, Liverpool, and Marseille), conventional field-based TV has been translated into image-guided high-precision craniospinal TV by a group of expert paediatric radiation oncologists and enhanced by MRI images of liquor distribution. RESULTS: The CTVcranial should include the whole brain, cribriform plate, most inferior part of the temporal lobes, and the pituitary fossa. If the full length of both optic nerves is not included, the dose received by different volumes of optic nerve should be recorded to correlate with future patterns of relapse (no consensus). The CTVcranial should be modified to include the dural cuffs of cranial nerves as they pass through the skull base foramina. Attempts to spare the cochlea by excluding CSF within the internal auditory canal should be avoided. The CTVspinal should include the entire subarachnoid space, including nerve roots laterally. The lower limit of the spinal CTV is at the lower limit of the thecal sac, best visible on MRI scan. There is no need to include sacral root canals in the spinal CTV. CONCLUSION: This consensus guideline has the potential to improve consistency of craniospinal TV delineation in an era of high-precision radiotherapy. This proposal will be incorporated in the RTQA guidelines of future SIOPE-BTG trials using CSI.

Quality assurance of radiotherapy in the ongoing EORTC 1219-DAHANCA-29 trial for HPV/p16 negative squamous cell carcinoma of the head and neck: Results of the benchmark case procedure.

BACKGROUND AND PURPOSE: The phase III EORTC 1219-DAHANCA 29 intergroup trial evaluates the influence of nimorazole in patients with locally advanced head and neck cancer when treated with accelerated radiotherapy (RT) in combination with chemotherapy. This article describes the results of the RT Benchmark Case (BC) performed before patient inclusion. MATERIALS AND METHODS: The participating centers were asked to perform a 2-step BC, consisting of (1) a delineation and (2) a planning exercise according to the protocol guidelines. Submissions were prospectively centrally reviewed and feedback was given to the submitting centers. Sørensen-Dice similarity index (DSI) and the 95th percentile Hausdorff distance (HD) were retrospectively used to evaluate the agreement between the centers and the expert contours. RESULTS: Fifty-four submissions (34 delineation and 20 planning exercises) from 19 centers were reviewed. Nine (47%) centers needed to perform the delineation step twice and three (16%) centers 3 times before receiving an approval. An increase in DSI-value and a decrease in HD, in particular for the prophylactic Clinical Target Volume (pCTV), could be found for the resubmitted cases. No unacceptable variations could be found for the planning exercise. CONCLUSIONS: These BC-results highlight the need for effective and prospective RTQA in clinical trials. Even with clearly defined protocol guidelines, delineation and not planning remain the main reason for unacceptable protocol variations. The introduction of more objective quantitative analysis methods, such as the HD and DSI, in future trials might strengthen the evaluation by experts.

Beam Output Audit results within the EORTC Radiation Oncology Group network.

Beam Output Auditing (BOA) is one key process of the EORTC radiation therapy quality assurance program. Here the results obtained between 2005 and 2014 are presented and compared to previous results.For all BOA reports the following parameters were scored: centre, country, date of audit, beam energies and treatment machines audited, auditing organisation, percentage of agreement between stated and measured dose.Four-hundred and sixty-one BOA reports were analyzed containing the results of 1790 photon and 1366 electron beams, delivered by 755 different treatment machines. The majority of beams (91.1%) were within the optimal limit of ≤ 3%. Only 13 beams (0.4%; n = 9 electrons; n = 4 photons), were out of the range of acceptance of ≤ 5%. Previous reviews reported a much higher percentage of 2.5% or more of the BOAs with >5% deviation.The majority of EORTC centres present beam output variations within the 3% tolerance cutoff value and only 0.4% of audited beams presented with variations of more than 5%. This is an important improvement compared to previous BOA results.