[Start of activity with the MRIdian® system: The first 200 patients treated at the Institut Paoli-Calmettes]. / Retour d'expérience clinique à propos des 200 premiers patients traités au MRIdian® à l'Institut Paoli-Calmettes.

INTRODUCTION: Several centers have recently been equipped with MRI-guided radiotherapy systems, including the Paoli-Calmettes Institute which was the first French center to start this activity. We report in this article our early experience. METHODS: Data related to patients treated on the MRIdian® (Viewray®) were prospectively collected. Procedures concerning the implementation of the system and internal organizational issues were summarized. RESULTS: Between February 2019 and March 2020, 201 patients were treated: 40% of treatments were normofractionated (n=70) and 60% used hypofractionation (n=105). The reported monthly occupancy rate at one, six and twelve months was 30%, 62%, and 90%. The distribution of normofractionated treatments was dominated by prostatic (29%) and pancreatic (26%) cancers, followed by abdomino-pelvic irradiations for gynecological cancers (12%) or lymph node diseases (12%) and boosts for rectal or vaginal cancers (11%). Regarding treatments with moderate hypofractionation (dose by fraction between 3 and 5Gy), they corresponded mainly to integrated boost for abdomino-pelvic lymph nodes (38%), while the stereotaxic treatments primarily concerned hepatic lesions (15%), bones (30%). DISCUSSION: The MRIdian® was initially used widely in our service corresponding to a learning curve for MRI guidance. This new tool for image-guided radiotherapy helped us to secure our practice providing solutions for both inter and intra-fraction movements making it possible to reduce the additional margin in order to better protect the organs at risk. The main technical difference with conventional accelerators is the possibility of performing adaptive radiotherapy in real time, the start of which was more gradual.

Oncologic outcomes in the era of modern radiation therapy using FIGO 2018 staging system for cervical cancer.

BACKGROUND: The recently published ASTRO cervical cancer guidelines recommend the use of modern radiotherapy. Imaging is now incorporated in the updated FIGO 2018 staging with a new stage IIIC. This study aims to evaluate the oncologic outcomes and predictors of survival using FIGO 2018 staging in a cohort of patients treated in an era of high-precision image-guided radiotherapy. METHODS: We performed a retrospective cohort study of 216 adult cervical cancer patients treated with definitive chemoradiotherapy between 2010 and 2018. Eligible patients had non-metastatic cervical cancer treated at a single academic institution. All patients had pre-treatment MRI and CT/PET. Treatment protocol consisted of external beam intensity-modulated radiotherapy and 3D image-guided brachytherapy. Kaplan-Meier curves were used for survival analysis. Multivariate cox proportional-hazards model was performed to identify potential prognostic factors. RESULTS: Median age at diagnosis was 50 and median BMI was 26.4 kg/m2. Median follow-up time was 44.3 months. Five-year overall survival (OS), disease-free survival and loco-regional disease-free survival rates were 76.8%, 68.5% and 82.6%, respectively. FIGO 2018 showed better OS discrimination compared to FIGO 2009 classification. OS was increasingly worse with positive pelvic and para-aortic nodes (p < 0.001). In a multivariate prediction model, performance status (p = 0.044) and FIGO 2018 classification (stage III p = 0.016; stage IVA p = 0.010) were predictors of mortality; FIGO 2018 classification (stage III p = 0.003; stage IVA p = 0.001) was a predictor of any recurrence; MRI tumor diameter (p ≤ 0.001) and nodal metastases (p = 0.024) were predictors of loco-regional recurrence. CONCLUSIONS: Integration of state-of-the-art imaging in cervical cancer staging and in radiotherapy planning leads to good loco-regional control rates, however distant recurrence remains an important issue. FIGO 2018 staging better reflects patient prognosis, highlighting the need for new treatment strategies for stage IIIC cervical cancer.

Treatment Volume, Dose Prescription and Delivery Techniques for Dose-intensification in Rectal Cancer: A National Survey.

BACKGROUND/AIM: The aim of the study was to investigate boost volume definition, doses, and delivery techniques for rectal cancer dose intensification. PATIENTS AND METHODS: An online survey was made on 25 items (characteristics, simulation, imaging, volumes, doses, planning and treatment). RESULTS: Thirty-eight radiation oncologists joined the study. Twenty-one delivered long-course radiotherapy with dose intensification. Boost volume was delineated on diagnostic magnetic resonance imaging (MRI) in 18 centres (85.7%), and computed tomography (CT) and/or positron emission tomography-CT in 9 (42.8%); 16 centres (76.2%) performed co-registration with CT-simulation. Boost dose was delivered on gross tumor volume in 10 centres (47.6%) and on clinical target volume in 11 (52.4%). The most common total dose was 54-55 Gy (71.4%), with moderate hypofractionation (85.7%). Intensity-modulated radiotherapy (IMRT) was used in all centres, with simultaneous integrated boost in 17 (80.8%) and image-guidance in 18 (85.7%). CONCLUSION: A high quality of treatment using dose escalation can be inferred by widespread multidisciplinary discussion, MRI-based treatment volume delineation, and radiation delivery relying on IMRT with accurate image-guided radiation therapy protocols.

Effect of Surgical Mask on Setup Error in Head and Neck Radiotherapy.

PURPOSE: With the widespread prevalence of Corona Virus Disease 2019 (COVID-19), cancer patients are suggested to wear a surgical mask during radiation treatment. In this study, cone beam CT (CBCT) was used to investigate the effect of surgical mask on setup errors in head and neck radiotherapy. METHODS: A total of 91 patients with head and neck tumors were selected. CBCT was performed to localize target volume after patient set up. The images obtained by CBCT before treatment were automatically registered with CT images and manually fine-tuned. The setup errors of patients in 6 directions of Vrt, Lng, Lat, Pitch, Roll and Rotation were recorded. The patients were divided into groups according to whether they wore the surgical mask, the type of immobilization mask used and the location of the isocenter. The setup errors of patients were calculated. A t-test was performed to detect whether it was statistically significant. RESULTS: In the 4 groups, the standard deviation in the directions of Lng and Pitch of the with surgical mask group were all higher than that in the without surgical mask group. In the head-neck-shoulder mask group, the mean in the Lng direction of the with surgical mask group was larger than that of the without surgical mask group. In the lateral isocenter group, the mean in the Lng and Pitch directions of the with surgical mask group were larger than that of the without surgical mask group. The t-test results showed that there was significant difference in the setup error between the 2 groups (p = 0.043 and p = 0.013, respectively) only in the Lng and Pitch directions of the head-neck-shoulder mask group. In addition, the setup error of 6 patients with immobilization open masks exhibited no distinguished difference from that of the patients with regular immobilization masks. CONCLUSION: In the head and neck radiotherapy patients, the setup error was affected by wearing surgical mask. It is recommended that the immobilization open mask should be used when the patient cannot finish the whole treatment with a surgical mask.

Modalities and techniques used for stereotactic radiotherapy, intensity-modulated radiotherapy, and image-guided radiotherapy: A 2018 survey by the Japan Society of Medical Physics.

Over the last several decades, there have been great advances in radiotherapy with the development of new technologies and modalities, and radiotherapy trends have changed rapidly. To comprehend the current state of radiotherapy in Japan, the QA/QC 2016-2017 Committee of the Japan Society of Medical Physics set up an intensity-modulated radiotherapy/image-guided radiotherapy (IMRT/IGRT) working group and performed a Web-based survey to show the current status of radiotherapy in Japan. The Web-based questionnaire, developed using Google Forms, contained 42 items: 7 on stereotactic radiotherapy implementation, 4 on IMRT, 24 on IGRT, and 7 on respiratory motion management. The survey was conducted from 17 January to 9 March of 2018; in total, 335 institutions provided data. The results show that volumetric modulated arc therapy was used at a level comparable to that of static gantry IMRT. For IGRT, machine-integrated computed tomography (CT), including kilovoltage or megavoltage cone-beam CT and megavoltage CT, was used at many institutions in conjunction with target-based image registration. For respiratory motion management, breath holding was the most commonly used technique. Our hope is that multi-institutional surveys such as this one will be conducted periodically to elucidate the current status of radiotherapy and emerging developments in this field. If our questionnaire was distributed worldwide, in the same format, then global trends in radiotherapy could be better understood.

The advanced radiotherapy network (ART-NET) UK lung stereotactic ablative radiotherapy survey: national provision and a focus on image guidance.

OBJECTIVE: Stereotactic ablative radiotherapy (SABR) has become the standard of care for suitable patients with peripherally located early stage non-small cell lung cancer. Lung SABR requires strict image-guided radiotherapy (IGRT) protocols to ensure its safe delivery. The aim of this survey was to provide an assessment of current lung SABR practice in the UK. METHODS: An online semi-structured survey containing a maximum of 32 questions regarding lung SABR, focussing on treatment image verification processes was piloted, developed and disseminated to the radiotherapy managers of 62 National Health Service centres across the UK. RESULTS: The survey had a 100% complete response from NHS centres. 36 centres (58%) currently deliver lung SABR, with half treating fewer than 50 patients per year. Six centres deliver SABR despite not being commissioned by the NHS to provide this service. There is wide variation in the use of IGRT. Eight different permutations of cone beam CT order within the workflow were reported. Almost half of lung centres (17/36, 47%) believe there is a need to update national image guidance associated with lung SABR, such as the use of 'day zero', mid treatment and post treatment cone beam CTs. CONCLUSION: Our results demonstrate wide variation in IGRT for lung SABR. There is an opportunity to develop existing IGRT workflows and the optimal approach to image guidance. Further work is required to investigate lung SABR provision and potential barriers to its implementation. ADVANCES IN KNOWLEDGE: This survey represents the most comprehensive and accurate assessment of lung SABR practice in the UK since the 2014 SABR consortium survey.

MRI-based tumor inter-fraction motion statistics for rectal cancer boost radiotherapy.

BACKGROUND: In patients diagnosed with rectal cancer, dose escalation is currently being investigated in a large number of studies. Since there is little known on gross tumor volume (GTV) inter-fraction motion for rectal cancer, a wide variety in margins is used. Purpose of this study is to quantify GTV inter-fraction motion statistics on different timescales and to give estimates of planning target volume (PTV) margins. MATERIAL AND METHODS: Thirty-two patients, diagnosed with rectal cancer, were included. To investigate motion from week-to-week, 16 patients underwent a pretreatment and five weekly MRIs, prior to a radiotherapy (RT) fraction of the chemoradiotherapy treatment. To investigate motion from day-to-day, the remaining 16 patients underwent five daily MRIs before each fraction in one week of RT. GTV was delineated on all scans according to guidelines. Scans were aligned on bony anatomy with the first MRI. For both datasets separately, GTV inter-fraction motion was determined based on center-of-gravity displacement. Therefrom, systematic and random errors were determined in left/right (LR), anterior/posterior and cranial/caudal (CC) direction. PTV margin estimates were calculated and evaluated on GTV coverage. RESULTS: Systematic and random errors were found in the range of 2.3-4.8 mm and 1.5-3.3 mm from week-to-week, and 1.8-4.5 mm and 1.8-4.0 mm from day-to-day, respectively. On both timescales, similar motion patterns were found; the most motion was observed in CC whilst the least motion was observed in LR. On the week-to-week data more systematic and less random motion was observed compared to the day-to-day data. Overall, only slight differences in margin estimates were found. Derived PTV margin estimates were found to give adequate GTV coverage. CONCLUSION: GTV inter-fraction motion, on a week-to-week and day-to-day timescale, can be accounted for using motion statistics presented in this study.

The impact of training and professional collaboration on the interobserver variation of lung cancer delineations: a multi-institutional study.

BACKGROUND: To assess the impact of training and interprofessional collaboration on the interobserver variation in the delineation of the lung gross tumor volume (GTVp) and lymph node (GTVln). MATERIAL AND METHODS: Eight target volume delineations courses were organized between 2008 and 2013. Specialists and trainees in radiation oncology were asked to delineate the GTVp and GTVln on four representative CT images of a patient diagnosed with lung cancer individually prior each course (baseline), together as group (interprofessional collaboration) and post-training. The mean delineated volume and local standard deviation (local SD) between the contours for each course group were calculated and compared with the expert delineations. RESULTS: A total 410 delineations were evaluated. The average local SD was lowest for the interprofessional collaboration (GTVp = 0.194 cm, GTVln = 0.371 cm) followed by the post-training (GTVp = 0.244 cm, GTVln = 0.607 cm) and baseline delineations (GTVp = 0.274 cm, GTVln: 0.718 cm). The mean delineated volume was smallest for the interprofessional (GTVp = 4.93 cm3, GTVln = 4.34 cm3) followed by the post-training (GTVp = 5.68 cm3, GTVln = 5.47 cm3) and baseline delineations (GTVp = 6.65 cm3, GTVln = 6.93 cm3). All delineations were larger than the expert for both GTVp and GTVln (p < .001). CONCLUSION: Our findings indicate that image interpretational differences can lead to large interobserver variation particularly when delineating the GTVln. Interprofessional collaboration was found to have the greatest impact on reducing interobserver variation in the delineation of the GTVln. This highlights the need to develop a clinical workflow so as to ensure that difficult cases are reviewed routinely by a second radiation oncologist or radiologist so as to minimize the risk of geographical tumor miss and unnecessary irradiation to normal tissue.

Patterns of Practice in Canadian Radiation Treatment Centres: Results of a National Survey.

PURPOSE: Radiation therapy has changed rapidly over the past decade due to the application of technological advances. A survey was conducted of radiation treatment centres in Canada to establish current patterns of practice across the country. Areas of inquiry included treatment techniques and image verification, as well as roles and responsibilities of radiation therapists (RTs). METHODS AND MATERIALS: In January 2016, a survey was sent to managers of the 46 radiation treatment centres in Canada. This survey sought information on a range of staffing and practice variables for the fiscal year 2014/2015. RESULTS: Of the 46 centres contacted, 37 centres responded, representing an 80.4% response rate. Survey results showed that the use of volumetric arc therapy and intensity-modulated radiation therapy is common across Canada for several anatomic sites, as well as the use of daily pretreatment image verification. A high degree of variability exists for imaging modality (two dimensional vs. three dimensional) for some sites, including brain, head and neck, and lung. RTs' responsibilities have expanded uniformly across the country, with RTs involved in organ-at-risk contouring and on-treatment image approval at the majority of centres. Despite this role expansion, specialty roles in areas of quality and applications expertise are still rare. CONCLUSIONS: Radiation therapy in Canada has transitioned to high-technology treatment techniques with relative consistency across the country. There is, however, variation in the imaging modality used for daily verification. Canada may benefit from consensus guidelines on the application of three-dimensional imaging for treatment verification. While RTs have expanded their responsibilities, role definition for RTs working in supervisory or supporting positions has not kept pace at many centres and it is unclear if RTs are supported in their expanded accountabilities.

Contouring workload in adjuvant breast cancer radiotherapy.

PURPOSE: To measure the impact of contouring on worktime in the adjuvant radiation treatment of breast cancer, and to identify factors that might affect the measurements. MATERIAL AND METHODS: The dates and times of contouring clinical target volumes and organs at risk were recorded by a senior and by two junior radiation oncologists. Outcome measurements were contour times and the time from start to approval. The factors evaluated were patient age, type of surgery, radiation targets and setup, operator, planning station, part of the day and day of the week on which the contouring started. The Welch test was used to comparatively assess the measurements. RESULTS: Two hundred and three cases were included in the analysis. The mean contour time per patient was 34minutes for a mean of 4.72 structures, with a mean of 7.1minutes per structure. The clinical target volume and organs at risk times did not differ significantly. The mean time from start to approval per patient was 29.4hours. Factors significantly associated with longer contour times were breast-conserving surgery (P=0.026), prone setup (P=0.002), junior operator (P<0.0001), Pinnacle planning station (P=0.026), contouring start in the morning (P=0.001), and contouring start by the end of the week (P<0.0001). Factors significantly associated with time from start to approval were age (P=0.038), junior operator (P<0.0001), planning station (P=0.016), and contouring start by the end of the week (P=0.004). CONCLUSION: Contouring is a time-consuming process. Each delineated structure influences worktime, and many factors may be targeted for optimization of the workflow. These preliminary data will serve as basis for future prospective studies to determine how to establish a cost-effective solution.

National survey of fiducial marker insertion for prostate image guided radiotherapy.

INTRODUCTION: In the United Kingdom fiducial marker IGRT is the second most common verification method employed in radical prostate radiotherapy yet little evidence exists to support centres introducing or developing this practice. We developed a survey to elicit current fiducial marker practices adopted in the UK, to recommend standardisation of practice. METHODS: A 16 question survey was distributed across UK Radiotherapy centres via promotion at the British Uro-Oncology Group Conference, 2016. Included were questions relating to workforce planning, patient preparation, insertion procedure and verification methods. The survey was open from September 2016 to January 2017. RESULTS: Results from 15 centres routinely inserting fiducial markers for prostate IGRT are presented. Eleven professional groups insert fiducial markers across the UK. Fourteen centres insert fiducial markers trans-rectally; one trans-perineally. Centres adopting a trans-rectal approach administer prophylactic ciprofloxacin as a single agent or combined with gentamicin or metronidazole; poor agreement between regimes presented. One centre has introduced targeted antibiotic prophylaxis. Five brands of fiducial markers are utilised nationally. Fourteen centres standardly insert three single fiducial markers, two common configurations emerged. Coupled fiducial markers are routinely implanted by one centre. All centres delay at least one week between fiducial marker insertion and planning CT; seven centres wait two weeks. The most common fiducial verification method is two-dimensional, paired kilo Voltage imaging. CONCLUSION: Variation in fiducial marker practice across the UK is considerable. Standardisation is required to support centres and healthcare professionals developing this service. Seven recommendations, to unify practice, have been proposed based on survey results and literature.

Tracking tumor boundary using point correspondence for adaptive radio therapy.

BACKGROUND AND OBJECTIVE: Tracking mobile tumor regions during the treatment is a crucial part of image-guided radiation therapy because of two main reasons which negatively affect the treatment process: (1) a tiny error will lead to some healthy tissues being irradiated; and (2) some cancerous cells may survive if the beam is not accurately positioned as it may not cover the entire cancerous region. However, tracking or delineation of such a tumor region from magnetic resonance imaging (MRI) is challenging due to photometric similarities of the region of interest and surrounding area as well as the influence of motion in the organs. The purpose of this work is to develop an approach to track the center and boundary of tumor region by auto-contouring the region of interest in moving organs for radiotherapy. METHODS: We utilize a nonrigid registration method as well as a publicly available RealTITracker algorithm for MRI to delineate and track tumor regions from a sequence of MRI images. The location and shape of the tumor region in the MRI image sequence varies over time due to breathing. We investigate two approaches: the first one uses manual segmentation of the first frame during the pretreatment stage; and the second one utilizes manual segmentation of all the frames during the pretreatment stage. RESULTS: We evaluated the proposed approaches over a sequence of 600 images acquired from 6 patients. The method that utilizes all the frames in the pretreatment stage with moving mesh based registration yielded the best performance with an average Dice Score of 0.89 ±â€¯0.04 and Hausdorff Distance of 3.38 ±â€¯0.10 mm. CONCLUSIONS: This study demonstrates a promising boundary tracking tool for delineating the tumor region that can deal with respiratory movement and the constraints of adaptive radiation therapy.

Contemporary prostate cancer radiation therapy in the United States: Patterns of care and compliance with quality measures.

PURPOSE: Quality measures represent the standards of appropriate treatment agreed upon by experts in the field and often supported by data. The extent to which providers in the community adhere to quality measures in radiation therapy (RT) is unknown. METHODS AND MATERIALS: The Comparative Effectiveness Analysis of Surgery and Radiation study enrolled men with clinically localized prostate cancer in 2011 and 2012. Patients completed surveys and medical records were reviewed. Patients were risk-stratified according to D'Amico classification criteria. Patterns of care and compliance with 8 quality measures as endorsed by national consortia as of 2011 were assessed. RESULTS: Overall, 926 men underwent definitive RT (69% external beam radiation therapy [EBRT]), 17% brachytherapy (BT), and 14% combined EBRT and BT with considerable variation in radiation techniques across risk groups. Most men who received EBRT had dose-escalated EBRT (>75 Gy; 93%) delivered with conventional fractionation (<2 Gy; 95%), intensity modulated RT (76%), and image guided RT (85%). Most men treated with BT received I125 (77%). Overall, 73% of the men received EBRT that was compliant with the quality measures (dose-escalation, image-guidance, appropriate use of androgen deprivation therapy, and appropriate treatment target) but only 60% of men received BT that was compliant with quality measures (postimplant dosimetry and appropriate dose). African-American men (64%) and other minorities (62%) were less likely than white men (77%) to receive EBRT that was compliant with quality measures. CONCLUSIONS: Most men who received RT for localized prostate cancer were treated with an appropriately high dose and received image guidance and intensity modulated RT. However, compliance with some nationally recognized quality measures was relatively low and varied by race. There are significant opportunities to improve the delivery of RT and especially for men of a minority race.

Contemporary Statewide Practice Pattern Assessment of the Palliative Treatment of Bone Metastasis.

PURPOSE: Palliative radiation therapy for bone metastases is often viewed as a single entity, despite national guidelines providing input principally only for painful uncomplicated bone metastases. Data surrounding the treatment of bone metastases are often gleaned from questionnaires of what providers would theoretically do in practice or from population-based data lacking critical granular information. We investigated the real-world treatment of bone metastases with radiation therapy. METHODS AND MATERIALS: Twenty diverse institutions across the state of Michigan had data extracted for their 10 most recent cases of radiation therapy delivered for the treatment of bone metastases at their institution between January and February 2017. Uni- and multivariable binary logistic regression was used to assess the use of single fraction (8 Gy × 1) radiation therapy. RESULTS: A total of 196 cases were eligible for inclusion. Twenty-eight different fractionation schedules were identified. The most common schedule was 3 Gy × 10 fractions (n = 100; 51.0%), 4 Gy × 5 fractions (n = 32; 16.3%), and 8 Gy × 1 (n = 15; 7.7%). The significant predictors for the use of single fraction radiation therapy were the presence of oligometastatic disease (P = .008), previous overlapping radiation therapy (P = .050), and academic practice type (P = .039). Twenty-nine cases (14.8%) received >10 fractions (median 15, range 11-20). Intensity modulated radiation therapy was used in 14 cases (7.1%), stereotactic body radiation therapy in 11 (5.6%), and image guidance with cone beam computed tomography in 11 (5.6%). Of the cases of simple painful bone metastases (no previous surgery, spinal cord compression, fracture, soft tissue extension, or overlapping previous radiation therapy; n = 70), only 12.9% were treated with 8 Gy × 1. CONCLUSIONS: Bone metastases represent a heterogeneous disease, and radiation therapy for bone metastases is similarly diverse. Future work is needed to understand the barriers to single fraction use, and clinical trials are necessary to establish appropriate guidelines for the breadth of this complex disease.

Inclusion of PET-CT into planning of primary or neoadjuvant chemoradiotherapy of esophageal cancer improves prognosis.

BACKGROUND: PET-CT is widely used for both the staging and planning of primary or neoadjuvant chemoradiotherapy for esophageal cancer. Inclusion of PET-CT information into radiotherapy planning often leads to substantial modifications of the target volume. In the case of detection of distant metastases, it may also result in a switch to a palliative treatment approach. This spares patients from therapy-related toxicities that provide no clinical benefit. However, due to a lack of studies, it is currently unclear whether the advantages of PET-CT also translate into a measurable improvement in patient survival. PATIENTS AND METHODS: A retrospective analysis assessed the survival data of 145 patients with esophageal carcinoma stages I (eight patients; 5%), II (45; 31%), III (79; 55%), IV (8; 5%) and unknown (5; 4%). Patients were treated between 1999 and 2014 either with primary chemoradiation (n = 101) or neoadjuvant chemoradiation at the Department of Radiation Oncology, University Medical Center Mainz, followed by transabdominal or transthoracic tumor resection (n = 44). Of the 145 patients, 64 (44%) had undergone PET-CT. RESULTS: Univariate analysis showed the use of PET-CT to be associated with significantly longer local recurrence-free survival (p = 0.006) and tended to translate into a measurable improvement of overall survival (p = 0.071). Since more patients underwent surgery in the group planned using PET-CT (20% vs. 44%; p = 0.002), we carried out a multivariate Cox regression analysis to adjust for this possible confounding factor. Surgery (p = 0.042; HR 0.55; 95% confidence interval: 0.31-0.98) as well as the use of PET-CT (p = 0.048; HR 0.60; 95% confidence interval: 0.36-0.99) nearly halved the risk of local recurrence. It was only in the group of patients with PET-CT that a trend towards a shorter overall survival was evident in lymph node-positive patients (p = 0.16), whereas nodal stage did not impact on survival in patients staged without PET-CT (p = 0.97). CONCLUSION: To the best of our knowledge these data suggest for the first time that the use of PET-CT in the framework of staging and planning of primary or neoadjuvant chemoradiotherapy for esophageal cancer has a favorable impact on patient survival.

Increased genitourinary fistula rate after bevacizumab in recurrent cervical cancer patients initially treated with definitive radiochemotherapy and image-guided adaptive brachytherapy.

BACKGROUND AND PURPOSE: Patients with recurrent cervical cancer (RecCC) who received definitive radiochemotherapy including image-guided adaptive brachytherapy (IGABT) as primary treatment are currently treated in our institution with palliative intent by chemotherapy (CHT) combined with bevacizumab (BEV). We aim to evaluate the risk of gastrointestinal (GI)/genitourinary (GU) fistula formation in these patients. MATERIALS AND METHODS: Data of 35 consecutive patients with RecCC treated initially with radiochemotherapy and IGABT were collected. Known and presumed risk factors associated with fistula formation were evaluated. Fistula rate was compared between patients receiving CHT or CHT+BEV. RESULTS: Of the 35 patients, 25 received CHT and 10 patients received CHT+BEV. Clinical characteristics were comparable. Fistulae were reported in 6 patients: two fistulae (8%) in the CHT group, four (40%) in the CHT+BEV group. GU fistula occurred in the CHT+BEV group only (3/4). Of these 6 patients with fistulae, 5 (83%) had undergone previous invasive procedures after the diagnosis of RecCC and 1 patient had undergone pelvic re-irradiation; 3/6 patients had developed a local recurrence. No other risk factors for fistula formation were identified. CONCLUSION: In patients with RecCC after definitive radiochemotherapy including IGABT, the addition of BEV to CHT may increase the risk for GU fistula formation, particularly after invasive pelvic procedures. Future clinical studies are required to identify predictors for fistula formation to subsequently improve patient selection for the addition of BEV in the RecCC setting.

Continued Benefit to Rectal Separation for Prostate Radiation Therapy: Final Results of a Phase III Trial.

PURPOSE: SpaceOAR, a Food and Drug Administration-approved hydrogel intended to create a rectal-prostate space, was evaluated in a single-blind phase III trial of image guided intensity modulated radiation therapy. A total of 222 men were randomized 2:1 to the spacer or control group and received 79.2 Gy in 1.8-Gy fractions to the prostate with or without the seminal vesicles. The present study reports the final results with a median follow-up period of 3 years. METHODS AND MATERIALS: Cumulative (Common Terminology Criteria for Adverse Events, version 4.0) toxicity was evaluated using the log-rank test. Quality of life (QOL) was examined using the Expanded Prostate Cancer Index Composite (EPIC), and the mean changes from baseline in the EPIC domains were tested using repeated measures models. The proportions of men with minimally important differences (MIDs) in each domain were tested using repeated measures logistic models with prespecified thresholds. RESULTS: The 3-year incidence of grade ≥1 (9.2% vs 2.0%; P=.028) and grade ≥2 (5.7% vs 0%; P=.012) rectal toxicity favored the spacer arm. Grade ≥1 urinary incontinence was also lower in the spacer arm (15% vs 4%; P=.046), with no difference in grade ≥2 urinary toxicity (7% vs 7%; P=0.7). From 6 months onward, bowel QOL consistently favored the spacer group (P=.002), with the difference at 3 years (5.8 points; P<.05) meeting the threshold for a MID. The control group had a 3.9-point greater decline in urinary QOL compared with the spacer group at 3 years (P<.05), but the difference did not meet the MID threshold. At 3 years, more men in the control group than in the spacer group had experienced a MID decline in bowel QOL (41% vs 14%; P=.002) and urinary QOL (30% vs 17%; P=.04). Furthermore, the control group were also more likely to have experienced large declines (twice the MID) in bowel QOL (21% vs 5%; P=.02) and urinary QOL (23% vs 8%; P=.02). CONCLUSIONS: The benefit of a hydrogel spacer in reducing the rectal dose, toxicity, and QOL declines after image guided intensity modulated radiation therapy for prostate cancer was maintained or increased with a longer follow-up period, providing stronger evidence for the benefit of hydrogel spacer use in prostate radiation therapy.

Survey of image-guided radiotherapy use in Australia.

INTRODUCTION: This study aimed to evaluate the current use of imaging technologies for planning and delivery of radiotherapy (RT) in Australia. METHODS: An online survey was emailed to all Australian RT centres in August 2015. The survey inquired about imaging practices during planning and treatment delivery processes. Participants were asked about the types of image-guided RT (IGRT) technologies and the disease sites they were used for, reasons for implementation, frequency of imaging and future plans for IGRT use in their department. RESULTS: The survey was completed by 71% of Australian RT centres. All respondents had access to computed tomography (CT) simulators and regularly co-registered the following scans to the RT: diagnostic CT (50%), diagnostic magnetic resonance imaging (MRI) (95%), planning MRI (34%), planning positron emission tomography (PET) (26%) and diagnostic PET (97%) to aid in tumour delineation. The main reason for in-room IGRT implementation was the use of highly conformal techniques, while the most common reason for under-utilisation was lack of equipment capability. The most commonly used IGRT modalities were kilovoltage (kV) cone-beam CT (CBCT) (97%), kV electronic portal image (EPI) (89%) and megavoltage (MV) EPI (75%). Overall, participants planned to increase IGRT use in planning (33%) and treatment delivery (36%). CONCLUSIONS: IGRT is widely used among Australian RT centres. On the basis of future plans of respondents, the installation of new imaging modalities is expected to increase for both planning and treatment.

Image-guided radiotherapy for prostate cancer in the United Kingdom: a national survey.

OBJECTIVE: To survey the technology and practice of image-guided radiotherapy (IGRT) for prostate cancer in the UK. METHODS: A pre-tested semi-structured online questionnaire was sent to National Health Service (NHS) and private radiotherapy providers in the UK between March and April 2014. The survey was carried out on the Opinio© online platform. RESULTS: There was a high survey response rate of 83%. There is widespread use of intensity-modulated radiotherapy and advanced verification imaging modalities. Cone-beam CT (CBCT) is the main verification imaging modality in radical prostate radiotherapy, used in 66% of UK centres. Fiducial markers in combination with imaging were used in 30% of centres. Over half the centres used a daily imaging schedule, with a Day 1-3 frequency followed by weekly frequency used less commonly. 26% of centres used daily CBCT. CONCLUSION: There is widespread use of volumetric verification imaging with CBCT for prostate radiotherapy in the UK. There is no consensus on the optimal verification imaging schedule. Advances in knowledge: This survey provides an insight into contemporary UK practice of IGRT for prostate cancer, both in the NHS and private sector. It demonstrates the widespread use of CBCT imaging and highlights the need for further research to optimize the practice.