Quality assurance in radiation oncology.

The Children's Oncology Group (COG) has a strong quality assurance (QA) program managed by the Imaging and Radiation Oncology Core (IROC). This program consists of credentialing centers and providing real-time management of each case for protocol compliant target definition and radiation delivery. In the International Society of Pediatric Oncology (SIOP), the lack of an available, reliable online data platform has been a challenge and the European Society for Paediatric Oncology (SIOPE) quality and excellence in radiotherapy and imaging for children and adolescents with cancer across Europe in clinical trials (QUARTET) program currently provides QA review for prospective clinical trials. The COG and SIOP are fully committed to a QA program that ensures uniform execution of protocol treatments and provides validity of the clinical data used for analysis.

A risk-based treatment strategy for non-rhabdomyosarcoma soft-tissue sarcomas in patients younger than 30 years (ARST0332): a Children's Oncology Group prospective study.

BACKGROUND: Tumour grade, tumour size, resection potential, and extent of disease affect outcome in paediatric non-rhabdomyosarcoma soft-tissue sarcoma (NRSTS), but no risk stratification systems exist and the standard of care is poorly defined. We developed a risk stratification system from known prognostic factors and assessed it in the context of risk-adapted therapy for young patients with NRSTS. METHODS: In this prospective study, eligible patients enrolled in 159 hospitals in three countries were younger than 30 years, had a Lansky (patients ≤16 years) or Karnofsky (patients >16 years) performance status score of at least 50, and a new diagnosis of a WHO (2002 criteria) intermediate (rarely metastasising) or malignant soft-tissue tumour (apart from tumour types eligible for other Children's Oncology Group studies and tumours for which the therapy in this trial was deemed inappropriate), malignant peripheral nerve sheath tumour, non-metastatic and grossly resected dermatofibrosarcoma protuberans, undifferentiated embryonal sarcoma of the liver, or unclassified malignant soft-tissue sarcoma. Each patient was assigned to one of three risk groups and one of four treatment groups. Risk groups were: low (non-metastatic R0 or R1 low-grade, or ≤5 cm R1 high-grade tumour); intermediate (non-metastatic R0 or R1 >5 cm high-grade, or unresected tumour of any size or grade); or high (metastatic tumour). The treatment groups were surgery alone, radiotherapy (55·8 Gy), chemoradiotherapy (chemotherapy and 55·8 Gy radiotherapy), and neoadjuvant chemoradiotherapy (chemotherapy and 45 Gy radiotherapy, then surgery and radiotherapy boost based on margins with continued chemotherapy). Chemotherapy included six cycles of ifosfamide 3 g/m2 per dose intravenously on days 1-3 and five cycles of doxorubicin 37·5 mg/m2 per dose intravenously on days 1-2 every 3 weeks with sequence adjusted on the basis of timing of surgery or radiotherapy. The primary outcomes were event-free survival, overall survival, and the pattern of treatment failure. Analysis was done per protocol. This study has been completed and is registered with ClinicalTrials.gov, NCT00346164. FINDINGS: Between Feb 5, 2007, and Feb 10, 2012, 550 eligible patients were enrolled, of whom 21 were treated in the incorrect group and excluded from this analysis. 529 evaluable patients were included in the analysis: low-risk (n=222), intermediate-risk (n=227), high-risk (n=80); surgery alone (n=205), radiotherapy (n=17), chemoradiotherapy (n=111), and neoadjuvant chemoradiotherapy (n=196). At a median follow-up of 6·5 years (IQR 4·9-7·9), 5-year event-free survival and overall survival were: 88·9% (95% CI 84·0-93·8) and 96·2% (93·2-99·2) in the low-risk group; 65·0% (58·2-71·8) and 79·2% (73·4-85·0) in the intermediate-risk group; and 21·2% (11·4-31·1) and 35·5% (23·6-47·4) in the high-risk group, respectively. Risk group predicted event-free survival and overall survival (p<0·0001). No deaths from toxic events during treatment were reported. Nine patients had unexpected grade 4 adverse events (chemoradiotherapy group, n=2; neoadjuvant chemoradiotherapy group, n=7), including three wound complications that required surgery (all in the neoadjuvant chemoradiotherapy group). INTERPRETATION: Pre-treatment clinical features can be used to effectively define treatment failure risk and to stratify young patients with NRSTS for risk-adapted therapy. Most low-risk patients can be cured without adjuvant therapy, thereby avoiding known long-term treatment complications. Survival remains suboptimal for intermediate-risk and high-risk patients and novel therapies are needed. FUNDING: National Institutes of Health, St Baldrick's Foundation, Seattle Children's Foundation, American Lebanese Syrian Associated Charities.

Practice patterns and recommendations for pediatric image-guided radiotherapy: A Children's Oncology Group report.

This report by the Radiation Oncology Discipline of Children's Oncology Group (COG) describes the practice patterns of pediatric image-guided radiotherapy (IGRT) based on a member survey and provides practice recommendations accordingly. The survey comprised of 11 vignettes asking clinicians about their recommended treatment modalities, IGRT preferences, and frequency of in-room verification. Technical questions asked physicists about imaging protocols, dose reduction, setup correction, and adaptive therapy. In this report, the COG Radiation Oncology Discipline provides an IGRT modality/frequency decision tree and the expert guidelines for the practice of ionizing image guidance in pediatric radiotherapy patients.

Feasibility and accuracy of UF/NCI phantoms and Monte Carlo retrospective dosimetry in children treated on National Wilms Tumor Study protocols.

PURPOSE: This pilot study was done to determine the feasibility and accuracy of University of Florida/National Cancer Institute (UF/NCI) phantoms and Monte Carlo (MC) retrospective dosimetry and had two aims: (1) to determine the anatomic accuracy of UF/NCI phantoms by comparing 3D organ doses in National Wilms Tumor Study (NWTS) patient-matched UF/NCI phantoms to organ doses in corresponding patient-matched CT scans and (2) to compare infield and out-of-field organ dosimetry using two dosimetry methods-standard radiation therapy (RT) treatment planning systems (TPS) and MC dosimetry in these two anatomic models. METHODS: Twenty NWTS patient-matched Digital Imaging and Communications in Medicine (DICOM) files of UF/NCI phantoms and CT scans were imported into the Pinnacle RT TPS. The NWTS RT fields (whole abdomen, flank, whole lung, or a combination) and RT doses (10-45 Gy) were reconstructed in both models. Both TPS and MC dose calculations were performed. For aim 1, the mean doses to the heart, kidney, thyroid gland, testes, and ovaries using TPS and MC in both models were statistically compared. For aim 2, the TPS and MC dosimetry for these organs in both models were statistically compared. RESULTS: For aim 1, there was no significant difference between phantom and CT scan dosimetry for any of the organs using either TPS or MC dosimetry. For aim 2, there was a significant difference between TPS and MC dosimetry for both CT scan and phantoms for all organs. Although the doses for infield organs were similar for both TPS and MC, the doses for near-field and out-of-field organs were consistently higher for 90% to 100% of MC doses; however, the absolute dose difference was small (<1 Gy). CONCLUSIONS: This pilot study has demonstrated that the patient-matched UF/NCI phantoms together with MC dosimetry is an accurate model for performing retrospective 3D dosimetry in large-scale epidemiology studies such as the NWTS.

Prognostic Factors in Limited-Stage Small Cell Lung Cancer: A Secondary Analysis of CALGB 30610-RTOG 0538.

Importance: The impact of patient-specific, disease-related, and social factors on outcomes in limited-stage small cell lung cancer (LS-SCLC) is not well defined. A post hoc secondary analysis of such factors from the Cancer and Leukemia Group B (CALGB) 30610-Radiation Therapy Oncology Group (RTOG) 0538 trial may impact future trial design. Objective: To assess the comprehensive demographic, disease-related, treatment-related, and social factors for potential associations with survival outcomes and understand whether specific subpopulations may benefit from radiotherapy (RT) dose escalation in LS-SCLC. Design, Setting, and Participants: This post hoc secondary analysis of a randomized clinical trial included 638 adults with LS-SCLC treated at 186 unique treatment sites with at least 1 accrual for all patients from March 15, 2008, to December 1, 2019; 313 patients were randomized to receive RT twice daily to a dosage of 45 Gy for 3 weeks and 325 to receive RT once daily to a dosage of 70 Gy for 7 weeks. Data were locked February 28, 2022, and analyzed from November 28, 2022, to June 4, 2024. Interventions: Twice-daily RT or once-daily RT. Main Outcomes and Measures: Multivariable Cox proportional hazards models evaluated the association of treatment groups and other risk factors with progression-free survival (PFS) and overall survival (OS). Patient-specific factors included age, sex, and Eastern Cooperative Oncology Group performance status. Disease-related factors included tumor, nodal, and overall cancer stages. Treatment-related factors included type of chemotherapy, timing of concurrent RT, RT technique, and prophylactic cranial irradiation. Social factors included marital status and treatment center accrual volume. Results: Among 507 patients (260 [51.3%] female and 247 [48.7%] male; mean [SD] age, 62.6 [7.9] years) included in the multivariate survival analysis, with a median follow-up of 4.7 (IQR, 3.7-7.1) years, female sex was associated with improved OS (hazard ratio [HR], 0.73 [95% CI, 0.58-0.91]; P = .006), while being 70 years or older was associated with decreased OS (HR, 1.50 [95% CI, 1.14-1.98]; P = .004). Neither age nor sex was associated with PFS. When compared with those with N1 disease, OS and PFS were worse in patients with N2 (HRs, 1.64 [95% CI, 1.19-2.26]; P = .002 and 1.36 [95% CI, 1.02-1.81]; P = .04, respectively) and N3 (HRs, 2.03 [95% CI, 1.40-2.93]; P < .001 and 1.63 [95% CI, 1.17-2.26]; P = .004) disease. Compared with stage II cancer, OS was worse for stage IIIA (HR, 1.65 [95% CI, 1.17-2.31]; P = .004) and stage IIIB (HR, 1.94 [95% CI, 1.34-2.83]; P < .001). Compared with high-volume accrual centers, treatment at low- or middle-volume accrual centers was associated with worse PFS (HRs, 1.94 [95% CI, 1.33-2.82; P < .001] and 1.44 [95% CI, 1.15-1.82; P = .002], respectively) and worse OS (HRs, 1.55 [95% CI, 1.03-2.32; P = .03] and 1.33 [95% CI, 1.04-1.70; P = .02], respectively). Conclusions and Relevance: This secondary analysis of the CALGB 30610-RTOG 0538 randomized clinical trial of patients with LS-SCLC found associations between female sex or being younger than 70 years and improved overall survival and between advanced nodal stage or treatment at low- or middle-volume accrual centers and worse outcomes. These findings suggest that stratification by nodal stage, clinical stage, and age should be considered in future randomized trials. Trial Registration: ClinicalTrials.gov Identifier: NCT00632853.

The Importance of Quality Assurance in Radiation Oncology Clinical Trials.

Clinical trials have been the center of progress in modern medicine. In oncology, we are fortunate to have a structure in place through the National Clinical Trials Network (NCTN). The NCTN provides the infrastructure and a forum for scientific discussion to develop clinical concepts for trial design. The NCTN also provides a network group structure to administer trials for successful trial management and outcome analyses. There are many important aspects to trial design and conduct. Modern trials need to ensure appropriate trial conduct and secure data management processes. Of equal importance is the quality assurance of a clinical trial. If progress is to be made in oncology clinical medicine, investigators and patient care providers of service need to feel secure that trial data is complete, accurate, and well-controlled in order to be confident in trial analysis and move trial outcome results into daily practice. As our technology has matured, so has our need to apply technology in a uniform manner for appropriate interpretation of trial outcomes. In this article, we review the importance of quality assurance in clinical trials involving radiation therapy. We will include important aspects of institution and investigator credentialing for participation as well as ongoing processes to ensure that each trial is being managed in a compliant manner. We will provide examples of the importance of complete datasets to ensure study interpretation. We will describe how successful strategies for quality assurance in the past will support new initiatives moving forward.

Quality improvements in radiation oncology clinical trials.

Clinical trials have become the primary mechanism to validate process improvements in oncology clinical practice. Over the past two decades there have been considerable process improvements in the practice of radiation oncology within the structure of a modern department using advanced technology for patient care. Treatment planning is accomplished with volume definition including fusion of multiple series of diagnostic images into volumetric planning studies to optimize the definition of tumor and define the relationship of tumor to normal tissue. Daily treatment is validated by multiple tools of image guidance. Computer planning has been optimized and supported by the increasing use of artificial intelligence in treatment planning. Informatics technology has improved, and departments have become geographically transparent integrated through informatics bridges creating an economy of scale for the planning and execution of advanced technology radiation therapy. This serves to provide consistency in department habits and improve quality of patient care. Improvements in normal tissue sparing have further improved tolerance of treatment and allowed radiation oncologists to increase both daily and total dose to target. Radiation oncologists need to define a priori dose volume constraints to normal tissue as well as define how image guidance will be applied to each radiation treatment. These process improvements have enhanced the utility of radiation therapy in patient care and have made radiation therapy an attractive option for care in multiple primary disease settings. In this chapter we review how these changes have been applied to clinical practice and incorporated into clinical trials. We will discuss how the changes in clinical practice have improved the quality of clinical trials in radiation therapy. We will also identify what gaps remain and need to be addressed to offer further improvements in radiation oncology clinical trials and patient care.

Radiation Oncology: Future Vision for Quality Assurance and Data Management in Clinical Trials and Translational Science.

The future of radiation oncology is exceptionally strong as we are increasingly involved in nearly all oncology disease sites due to extraordinary advances in radiation oncology treatment management platforms and improvements in treatment execution. Due to our technology and consistent accuracy, compressed radiation oncology treatment strategies are becoming more commonplace secondary to our ability to successfully treat tumor targets with increased normal tissue avoidance. In many disease sites including the central nervous system, pulmonary parenchyma, liver, and other areas, our service is redefining the standards of care. Targeting of disease has improved due to advances in tumor imaging and application of integrated imaging datasets into sophisticated planning systems which can optimize volume driven plans created by talented personnel. Treatment times have significantly decreased due to volume driven arc therapy and positioning is secured by real time imaging and optical tracking. Normal tissue exclusion has permitted compressed treatment schedules making treatment more convenient for the patient. These changes require additional study to further optimize care. Because data exchange worldwide have evolved through digital platforms and prisms, images and radiation datasets worldwide can be shared/reviewed on a same day basis using established de-identification and anonymization methods. Data storage post-trial completion can co-exist with digital pathomic and radiomic information in a single database coupled with patient specific outcome information and serve to move our translational science forward with nimble query elements and artificial intelligence to ask better questions of the data we collect and collate. This will be important moving forward to validate our process improvements at an enterprise level and support our science. We have to be thorough and complete in our data acquisition processes, however if we remain disciplined in our data management plan, our field can grow further and become more successful generating new standards of care from validated datasets.

Local Control For High-Grade Nonrhabdomyosarcoma Soft Tissue Sarcoma Assigned to Radiation Therapy on ARST0332: A Report From the Childrens Oncology Group.

PURPOSE: The ARST0332 trial for pediatric and young adults with nonrhabdomyosarcoma soft tissue sarcoma (NRSTS) used risk-based treatment including primary resection with lower-than-standard radiation doses to optimize local control (LC) while minimizing long-term toxicity in those requiring radiation therapy (RT). RT for high-grade NRSTS was based on extent of resection (R0: negative margins, R1: microscopic margins, R2/U: gross disease/unresectable); those with >5 cm tumors received chemotherapy (CT; ifosfamide/doxorubicin). This analysis evaluates LC for patients assigned to RT and prognostic factors associated with local recurrence (LR). METHODS AND MATERIALS: Patients aged <30 years with high-grade NRSTS received RT (55.8 Gy) for R1 ≤5 cm tumor (arm B); RT (55.8 Gy)/CT for R0/R1 >5 cm tumor (arm C); or neoadjuvant RT (45 Gy)/CT plus delayed surgery, CT, and postoperative boost to 10.8 Gy R0 <5 mm margins/R1 or 19.8 Gy for R2/unresected tumors (arm D). RESULTS: One hundred ninety-three eligible patients had 24 LRs (arm B 1/15 [6.7%], arm C 7/65 [10.8%], arm D 16/113 [14.2%]) at median time to LR of 1.1 years (range, 0.11-5.27). Of 95 eligible for delayed surgery after neoadjuvant therapy, 89 (93.7%) achieved R0/R1 margins. Overall LC after RT were as follows: R0, 106 of 109 (97%); R1, 51 of 60 (85%); and R2/unresectable, 2 of 6 (33%). LR predictors include extent of delayed resection (P <.001), imaging response before delayed surgery (P < .001), histologic subtype (P <.001), and no RT (P = .046). The 5-year event-free survival was significantly lower (P = .0003) for patients unable to undergo R0/R1 resection. CONCLUSIONS: Risk-based treatment for young patients with high-grade NRSTS treated on ARST0332 produced very high LC, particularly after R0 resection (97%), despite lower-than-standard RT doses. Neoadjuvant CT/RT enabled delayed R0/R1 resection in most patients and is preferred over adjuvant therapy due to the lower RT dose delivered.

Treatment Toxicity: Radiation.

Intentional and unintentional radiation exposures have a powerful impact on normal tissue function and can induce short-term and long-term injury to all cell systems. Radiation effects can lead to lifetime-defining health issues for a patient and can produce complications to all organ systems. Providers need to understand acute and late effects of radiation treatment and how the fingerprints of therapy can have an impact on health care in later life. This article reviews current knowledge concerning normal tissue tolerance with therapy.

Preoperative Intensity Modulated Radiation Therapy Compared to Three-Dimensional Conformal Radiation Therapy for High-Grade Extremity Sarcomas in Children: Analysis of the Children's Oncology Group Study ARST0332.

PURPOSE: For pediatric patients with large, high-grade, extremity nonrhabdomyosarcoma soft-tissue sarcomas, preoperative radiation therapy (RT) provides the opportunity for smaller radiation fields and tumor shrinkage resulting in less extensive surgery. The potential disadvantage is an increased risk of wound complications after surgery compared with rates after postoperative chemoradiation. We assessed the impact of preoperative RT technique on target coverage in relationship to dose to skin and adjacent joints to determine whether acute wound complications and late musculoskeletal injury might be influenced by treatment technique. METHODS AND MATERIALS: Of 550 eligible patients <30 years of age, 200 were enrolled in arm D of ARST0332 and received neoadjuvant ifosfamide/doxorubicin, then chemoradiotherapy (45 Gy and ifosfamide) and surgery followed by postoperative RT if gross or microscopic positive surgical margins. One-hundred thirteen patients had extremity nonrhabdomyosarcoma soft-tissue sarcomas, of which 56 patients had preoperative RT plans for digital review. The doses to the target volume, skin (surface to 5 mm depth), adjacent joint, and extremity diameter were analyzed with respect to RT technique. RESULTS: Thirty-eight patients (65%) received 3-dimensional conformal RT (3D-CRT) and 18 (32%) received intensity modulated RT (IMRT). There was no difference in clinical target volume (CTV) size between groups (P = .920); however, IMRT plans had improved CTV coverage to 100% of the prescription dose compared with 3D-CRT plans (median CTV coverage, 92.7% vs 98.6%; P = .011). In patients without target overlap with the skin, IMRT use was associated with reduced percent volume of skin receiving 45 Gy or more (V45Gy) compared with 3D-CRT (median, 1.6% vs 6.3%, respectively; P = .005). IMRT was also associated with reduced V45Gy to the adjacent joint compared with 3D-CRT (median, 1.1% vs 13.2%; P = .018). CONCLUSIONS: Preoperative IMRT may improve CTV coverage and reduce the volume of skin and adjacent joint treated to high doses. Future studies should assess whether these dosimetric findings produce differences in clinical and toxicity outcomes.

Cardiac-Sparing Whole Lung IMRT in Patients With Pediatric Tumors and Lung Metastasis: Final Report of a Prospective Multicenter Clinical Trial.

PURPOSE: A prospective clinical trial was conducted for patients undergoing cardiac sparing (CS) whole lung irradiation (WLI) using intensity modulated radiation therapy (IMRT). The 3 trial aims were (1) to demonstrate the feasibility of CS IMRT with real-time central quality control; (2) to determine the dosimetric advantages of WLI using IMRT compared with standard anteroposterior (AP) techniques; and (3) to determine acute tolerance and short-term efficacy after a protocol-mandated minimum 2-year follow-up for all patients. METHODS AND MATERIALS: All patients underwent a 3-dimensional chest computed tomography scan and a contrast-enhanced 4-dimensional (4D) gated chest computed tomography scan using a standard gating device. The clinical target volume was the entire bilateral 3-dimensional lung volume, and the internal target volume was the 4D minimum intensity projection of both lungs. The internal target volume was expanded by 1 cm to get the planning target volume. All target volumes, cardiac contours, and treatment plans were centrally reviewed before treatment. The different cardiac volumes receiving percentages of prescribed radiation therapy (RT) doses on AP and IMRT WLI plans were estimated and compared. RESULTS: The target 20 patients were accrued in 2 years. Median RT dose was 15 Gy. Real-time central quality assurance review and plan preapproval were obtained for all patients. WLI using IMRT was feasible in all patients. Compared with standard AP WLI, CS IMRT resulted in a statistically significant reduction in radiation doses to the whole heart, atria, ventricles, and coronaries. One child developed cardiac dysfunction and pulmonary restrictive disease 5.5 years after CS IMRT (15 Gy) and doxorubicin (375 mg/m2). The 2- and 3-year lung metastasis progression-free survival was 65% and 52%, respectively. CONCLUSIONS: We have demonstrated the feasibility of WLI using CS IMRT and confirmed the previously reported advantages of IMRT, including superior cardiac protection and superior dose coverage of 4D lung volumes. Further studies are required to establish the efficacy and safety of this irradiation technique.

Higher Reported Lung Dose Received During Total Body Irradiation for Allogeneic Hematopoietic Stem Cell Transplantation in Children With Acute Lymphoblastic Leukemia Is Associated With Inferior Survival: A Report from the Children's Oncology Group.

PURPOSE: To examine the relationship between lung radiation dose and survival outcomes in children undergoing total body irradiation (TBI)-based hematopoietic stem cell transplantation (HSCT) for acute lymphoblastic leukemia on the Children's Oncology Group trial. METHODS AND MATERIALS: TBI (1200 or 1320 cGy given twice daily in 6 or 8 fractions) was used as part of 3 HSCT preparative regimens, allowing institutional flexibility regarding TBI techniques, including lung shielding. Lung doses as reported by each participating institution were calculated for different patient setups, with and without shielding, with a variety of dose calculation techniques. The association between lung dose and transplant-related mortality, relapse-free survival, and overall survival (OS) was examined using the Cox proportional hazards regression model controlling for the following variables: TBI dose rate, TBI fields, patient position during TBI, donor type, and pre-HSCT minimal residual disease level. RESULTS: Of a total of 143 eligible patients, 127 had lung doses available for this analysis. The TBI techniques were heterogeneous. The mean lung dose was reported as 904.5 cGy (standard deviation, ±232.3). Patients treated with lateral fields were more likely to receive lung doses ≥800 cGy (P < .001). The influence of lung dose ≥800 cGy on transplant-related mortality was not significant (hazard ratio [HR], 1.78; P = .21). On univariate analysis, lung dose ≥800 cGy was associated with inferior relapse-free survival (HR, 1.76; P = .04) and OS (HR, 1.85; P = .03). In the multivariate analysis, OS maintained statistical significance (HR, 1.85; P = .04). CONCLUSIONS: The variability in TBI techniques resulted in uncertainty with reported lung doses. Lateral fields were associated with higher lung dose, and thus they should be avoided. Patients treated with lung dose <800 cGy in this study had better outcomes. This approach is currently being investigated in the Children's Oncology Group AALL1331 study. Additionally, the Imaging and Radiation Oncology Core Group is evaluating effects of TBI techniques on lung doses using a phantom.

An in-silico quality assurance study of contouring target volumes in thoracic tumors within a cooperative group setting.

INTRODUCTION: Target delineation variability is a significant technical impediment in multi-institutional trials which employ intensity modulated radiotherapy (IMRT), as there is a real potential for clinically meaningful variances that can impact the outcomes in clinical trials. The goal of this study is to determine the variability of target delineation among participants from different institutions as part of Southwest Oncology Group (SWOG) Radiotherapy Committee's multi-institutional in-silico quality assurance study in patients with Pancoast tumors as a "dry run" for trial implementation. METHODS: CT simulation scans were acquired from four patients with Pancoast tumor. Two patients had simulation 4D-CT and FDG-FDG PET-CT while two patients had 3D-CT and FDG-FDG PET-CT. Seventeen SWOG-affiliated physicians independently delineated target volumes defined as gross primary and nodal tumor volumes (GTV_P & GTV_N), clinical target volume (CTV), and planning target volume (PTV).Six board-certified thoracic radiation oncologists were designated as the 'Experts' for this study. Their delineations were used to create a simultaneous truth and performance level estimation (STAPLE) contours using ADMIRE software (Elekta AB, Sweden 2017). Individual participants' contours were then compared with Experts' STAPLE contours. RESULTS: When compared to the Experts' STAPLE, GTV_P had the best agreement among all participants, while GTV_N showed the lowest agreement among all participants. There were no statistically significant differences in all studied parameters for all TVs for cases with 4D-CT versus cases with 3D-CT simulation scans. CONCLUSIONS: High degree of inter-observer variation was noted for all target volume except for GTV_P, unveiling potentials for protocol modification for subsequent clinically meaningful improvement in target definition. Various similarity indices exist that can be used to guide multi-institutional radiotherapy delineation QA credentialing.

Processes for quality improvements in radiation oncology clinical trials.

Quality assurance in radiotherapy (RT) has been an integral aspect of cooperative group clinical trials since 1970. In early clinical trials, data acquisition was nonuniform and inconsistent and computational models for radiation dose calculation varied significantly. Process improvements developed for data acquisition, credentialing, and data management have provided the necessary infrastructure for uniform data. With continued improvement in the technology and delivery of RT, evaluation processes for target definition, RT planning, and execution undergo constant review. As we move to multimodality image-based definitions of target volumes for protocols, future clinical trials will require near real-time image analysis and feedback to field investigators. The ability of quality assurance centers to meet these real-time challenges with robust electronic interaction platforms for imaging acquisition, review, archiving, and quantitative review of volumetric RT plans will be the primary challenge for future successful clinical trials.

Patterns of Involved-Field Radiation Therapy Protocol Deviations in Pediatric Versus Adolescent and Young Adults With Hodgkin Lymphoma: A Report From the Children's Oncology Group AHOD0031.

PURPOSE: The presented protocol for pediatric intermediate-risk Hodgkin lymphoma evaluated the use of a dose-intensive chemotherapy regimen (ABVE-PC [doxorubicin, bleomycin, vincristine, etoposide, cyclophosphamide, prednisone]) with response-based therapy augmentation (addition of DECA [dexamethasone, etoposide, cisplatin, cytarabine]) or therapy reduction (elimination of radiation). METHODS AND MATERIALS: A central review of the radiation therapy data for quality assurance was performed, and the association between radiation protocol deviation (RPD) and relapse was assessed in the pediatric group (age <15 years) and adolescent and young adult (AYA) group (age ≥15-21 years). Involved-field radiation therapy (IFRT) planning was reviewed before the start of treatment and at treatment completion. The records were reviewed through the Quality Assurance Review Center's central review to identify RPD, classified according to dose deviation (DD), volume deviation (VD), undertreatment (UT), and overtreatment (OT). DDs and VDs were further classified as major or minor. RESULTS: Of the 1712 patients enrolled, 1155 received IFRT, of whom, 216 (18.7%) had RPDs. The DD and VD patterns were similar between the pediatric and AYA groups. Minor VDs were most common. UT RPDs accounted for 69% in the pediatric group and 75% in the AYA group. Of the 35 patients with relapse and a RPD, 29 had an undertreatment RPD. Among the patients who received IFRT, a significant difference was found in the cumulative incidence rates of relapse between the pediatric and AYA groups (P = .03); however, no significant difference was found between patients with and without RPD (P = .2). CONCLUSIONS: Most RPDs were minor and consisted of UT in the AYA and pediatric populations both. No difference was observed in RPDs between the pediatric and AYA patients. Thus, in a well-defined and standardized protocol, the RPD distributions for AYA patients will be similar to those for pediatric population. However, the increased cumulative incidence of relapse in the AYA patients who had received IFRT compared with the pediatric population requires further exploration, given the potential differences in clinical outcomes in the AYA population.

The Importance of Imaging in Radiation Oncology for National Clinical Trials Network Protocols.

Imaging is essential in successfully executing radiation therapy (RT) in oncology clinical trials. As technically sophisticated diagnostic imaging and RT were incorporated into trials, quality assurance in the National Clinical Trials Network groups entered a new era promoting image acquisition and review. Most trials involving RT require pre- and post-therapy imaging for target validation and outcome assessment. The increasing real-time (before and during therapy) imaging and RT object reviews are to ensure compliance with trial objectives. Objects easily transmit digitally for review from anywhere in the world. Physician interpretation of imaging and image application to RT treatment plans is essential for optimal trial execution. Imaging and RT data sets are used to credential RT sites to confirm investigator and institutional ability to meet trial target volume delineation and delivery requirements. Real-time imaging and RT object reviews can be performed multiple times during a trial to assess response to therapy and application of RT objects. This process has matured into an effective data management mechanism. When necessary, site and study investigators review objects together through web media technologies to ensure the patient is enrolled on the appropriate trial and the intended RT is planned and executed in a trial-compliant manner. Real-time imaging review makes sure: (1) the patient is entered and eligible for the trial, (2) the patient meets trial-specific adaptive therapy requirements, if applicable, and (3) the intended RT is according to trial guidelines. This review ensures the study population is uniform and the results are believable and can be applied to clinical practice.

The Children's Oncology Group Radiation Oncology Discipline: 15 Years of Contributions to the Treatment of Childhood Cancer.

PURPOSE: Our aim was to review the advances in radiation therapy for the management of pediatric cancers made by the Children's Oncology Group (COG) radiation oncology discipline since its inception in 2000. METHODS AND MATERIALS: The various radiation oncology disease site leaders reviewed the contributions and advances in pediatric oncology made through the work of the COG. They have presented outcomes of relevant studies and summarized current treatment policies developed by consensus from experts in the field. RESULTS: The indications and techniques for pediatric radiation therapy have evolved considerably over the years for virtually all pediatric tumor types, resulting in improved cure rates together with the potential for decreased treatment-related morbidity and mortality. CONCLUSIONS: The COG radiation oncology discipline has made significant contributions toward the treatment of childhood cancer. Our discipline is committed to continuing research to refine and modernize the use of radiation therapy in current and future protocols with the goal of further improving the cure rates and quality of life of children with cancer.

Report from the SWOG Radiation Oncology Committee: Research Objectives Workshop 2017.

The Radiation Therapy Committee of SWOG periodically evaluates its strategic plan in an effort to maintain a current and relevant scientific focus, and to provide a standard platform for future development of protocol concepts. Participants in the 2017 Strategic Planning Workshop included leaders in cancer basic sciences, molecular theragnostics, pharmaceutical and technology industries, clinical trial design, oncology practice, and statistical analysis. The committee discussed high-priority research areas, such as optimization of combined modality therapy, radiation oncology-specific drug design, identification of molecular profiles predictive of radiation-induced local or distant tumor responses, and methods for normal tissue-specific mitigation of radiation toxicity. The following concepts emerged as dominant questions ready for national testing: (i) what is the role of radiotherapy in the treatment of oligometastatic, oligorecurrent, and oligoprogressive disease? (ii) How can combined modality therapy be used to enhance systemic and local response? (iii) Can we validate and optimize liquid biopsy and other biomarkers (such as novel imaging) to supplement current response criteria to guide therapy and clinical trial design endpoints? (iv) How can we overcome deficiencies of randomized survival endpoint trials in an era of increasing molecular stratification factors? And (v) how can we mitigate treatment-related side effects and maximize quality of life in cancer survivors? The committee concluded that many aspects of these questions are ready for clinical evaluation and example protocol concepts are provided that could improve rates of cancer cure and quality of survival. Clin Cancer Res; 24(15); 3500-9. ©2018 AACR.

Radiotherapy in pediatric medulloblastoma: quality assessment of Pediatric Oncology Group Trial 9031.

PURPOSE: To evaluate the potential influence of radiotherapy quality on survival in high-risk pediatric medulloblastoma patients. METHODS AND MATERIALS: Trial 9031 of the Pediatric Oncology Group (POG) aimed to study the relative benefit of cisplatin and etoposide randomization of high-risk patients with medulloblastoma to preradiotherapy vs. postradiotherapy treatment. Two-hundred and ten patients were treated according to protocol guidelines and were eligible for the present analysis. Treatment volume (whole brain, spine, posterior fossa, and primary tumor bed) and dose prescription deviations were assessed for each patient. An analysis of first site of failure was undertaken. Event-free and overall survival rates were calculated. A log-rank test was used to determine the significance of potential survival differences between patients with and without major deviations in the radiotherapy procedure. RESULTS: Of 160 patients who were fully evaluable for all treatment quality parameters, 91 (57%) had 1 or more major deviations in their treatment schedule. Major deviations by treatment site were brain (26%), spinal (7%), posterior fossa (40%), and primary tumor bed (17%). Major treatment volume or total dose deviations did not significantly influence overall and event-free survival. CONCLUSIONS: Despite major treatment deviations in more than half of fully evaluable patients, underdosage or treatment volume misses were not associated with a worse event-free or overall survival.