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This position paper, led by the NRG Oncology Particle Therapy Work Group, focuses on the concept of relative biologic effect (RBE) in clinical proton therapy (PT), with the goal of providing recommendations for the next-generation clinical trials with PT on the best practice of investigating and using RBE, which could deviate from the current standard proton RBE value of 1.1 relative to photons. In part 1, current clinical utilization and practice are reviewed, giving the context and history of RBE. Evidence for variation in RBE is presented along with the concept of linear energy transfer (LET). The intertwined nature of tumor radiobiology, normal tissue constraints, and treatment planning with LET and RBE considerations is then reviewed. Part 2 summarizes current and past clinical data and then suggests the next steps to explore and employ tools for improved dynamic models for RBE. In part 3, approaches and methods for the next generation of prospective clinical trials are explored, with the goal of optimizing RBE to be both more reflective of clinical reality and also deployable in trials to allow clinical validation and interpatient comparisons. These concepts provide the foundation for personalized biologic treatments reviewed in part 4. Finally, we conclude with a summary including short- and long-term scientific focus points for clinical PT. The practicalities and capacity to use RBE in treatment planning are reviewed and considered with more biological data in hand. The intermediate step of LET optimization is summarized and proposed as a potential bridge to the ultimate goal of case-specific RBE planning that can be achieved as a hypothesis-generating tool in near-term proton trials.
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Importance: The optimal radiotherapy technique for unresectable locally advanced non-small cell lung cancer (NSCLC) is controversial, so evaluating long-term prospective outcomes of intensity-modulated radiotherapy (IMRT) is important. Objective: To compare long-term prospective outcomes of patients receiving IMRT and 3-dimensional conformal radiotherapy (3D-CRT) with concurrent carboplatin/paclitaxel for locally advanced NSCLC. Design, Setting, and Participants: A secondary analysis of a prospective phase 3 randomized clinical trial NRG Oncology-RTOG 0617 assessed 483 patients receiving chemoradiotherapy (3D-CRT vs IMRT) for locally advanced NSCLC based on stratification. Main Outcomes and Measures: Long-term outcomes were analyzed, including overall survival (OS), progression-free survival (PFS), time to local failure, development of second cancers, and severe grade 3 or higher adverse events (AEs) per Common Terminology Criteria for Adverse Events, version 3. The percentage of an organ volume (V) receiving a specified amount of radiation in units of Gy is reported as V(radiation dose). Results: Of 483 patients (median [IQR] age, 64 [57-70] years; 194 [40.2%] female), 228 (47.2%) received IMRT, and 255 (52.8%) received 3D-CRT (median [IQR] follow-up, 5.2 [4.8-6.0] years). IMRT was associated with a 2-fold reduction in grade 3 or higher pneumonitis AEs compared with 3D-CRT (8 [3.5%] vs 21 [8.2%]; P = .03). On univariate analysis, heart V20, V40, and V60 were associated with worse OS (hazard ratios, 1.06 [95% CI, 1.04-1.09]; 1.09 [95% CI, 1.05-1.13]; 1.16 [95% CI, 1.09-1.24], respectively; all P < .001). IMRT significantly reduced heart V40 compared to 3D-CRT (16.5% vs 20.5%; P < .001). Heart V40 (<20%) had better OS than V40 (≥20%) (median [IQR], 2.5 [2.1-3.1] years vs 1.7 [1.5-2.0] years; P < .001). On multivariable analysis, heart V40 (≥20%), was associated with worse OS (hazard ratio, 1.34 [95% CI, 1.06-1.70]; P = .01), whereas lung V5 and age had no association with OS. Patients receiving IMRT and 3D-CRT had similar rates of developing secondary cancers (15 [6.6%] vs 14 [5.5%]) with long-term follow-up. Conclusions and Relevance: These findings support the standard use of IMRT for locally advanced NSCLC. IMRT should aim to minimize lung V20 and heart V20 to V60, rather than constraining low-dose radiation bath. Lung V5 and age were not associated with survival and should not be considered a contraindication for chemoradiotherapy. Trial Registration: ClinicalTrials.gov Identifier: NCT00533949.
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Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Radioterapia de Intensidad Modulada , Humanos , Radioterapia de Intensidad Modulada/efectos adversos , Radioterapia de Intensidad Modulada/métodos , Persona de Mediana Edad , Femenino , Masculino , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/patología , Anciano , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Carcinoma de Pulmón de Células no Pequeñas/patología , Estudios Prospectivos , Resultado del Tratamiento , Quimioradioterapia/métodos , Paclitaxel/administración & dosificación , Paclitaxel/uso terapéutico , Radioterapia Conformacional/efectos adversos , Radioterapia Conformacional/métodos , Carboplatino/administración & dosificación , Carboplatino/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Supervivencia sin ProgresiónRESUMEN
Although standardization has been shown to improve patient safety and improve the efficiency of workflows, implementation of standards can take considerable effort and requires the engagement of all clinical stakeholders. Engaging team members includes increasing awareness of the proposed benefit of the standard, a clear implementation plan, monitoring for improvements, and open communication to support successful implementation. The benefits of standardization often focus on large institutions to improve research endeavors, yet all clinics can benefit from standardization to increase quality and implement more efficient or automated workflow. The benefits of nomenclature standardization for all team members and institution sizes, including success stories, are discussed with practical implementation guides to facilitate the adoption of standardized nomenclature in radiation oncology.
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Purpose: The purpose of this study was to analyze the impact of prostate rectal spacers on sexual quality of life (QOL) following external beam radiation therapy (RT). Methods and materials: Patient- reported QOL was evaluated using the Expanded Prostate Cancer Index Composite (EPIC). Patients were pooled from two sources: a randomized controlled trial and a non-randomized cohort of patients from a single institution. Both cohorts used the same spacing product and QOL instrument. Analysis was limited to those with good baseline pre-treatment sexual QOL (EPIC >/= 60). Differences in QOL summary score and individual items were assessed compared with baseline and between treatment arms. Results: A total of 128 men had good baseline sexual function and were evaluated (64% with spacer and 36% without) with QOL data available for median 33 months (range: 2.5-69.4 months). Men without spacer were more likely to have declines in sexual function (p < 0.0001), bother (p = 0.0002), and sexual summary score (p < 0.0001). A minimally important difference of 10 points (1xMID) and 20 point (2xMID) was more likely without rectal spacer [10 points: odds ratio 3.53, (95% confidence interval 1.11-11.2), p = 0.032; 20 points: odds ratio 3.29, (95% confidence interval 1.16-9.33), p = 0.025]. Seven of 13 QOL items were statistically superior with hydrogel (six of nine functional and one of four bother), while no items were statistically superior for control. At baseline, more men treated with hydrogel had erections sufficient for intercourse; however, when analyzed only by the men with best baseline erectile potential and excluding those with worse function, the benefit of rectal spacing was maintained with a higher likelihood of preservation of erections sufficient for intercourse in those treated with hydrogel. Conclusion: In this pooled analysis of QOL after prostate RT, the utilization of a hydrogel spacer was associated with better sexual QOL, less men with measurable declines in sexual QOL, and higher rates of adequate erectile function.
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PURPOSE: To determine whether addition of external beam radiation therapy (EBRT) to brachytherapy (BT) (COMBO) compared with BT alone would improve 5-year freedom from progression (FFP) in intermediate-risk prostate cancer. METHODS: Men with prostate cancer stage cT1c-T2bN0M0, Gleason Score (GS) 2-6 and prostate-specific antigen (PSA) 10-20 or GS 7, and PSA < 10 were eligible. The COMBO arm was EBRT (45 Gy in 25 fractions) to prostate and seminal vesicles followed by BT prostate boost (110 Gy if 125-Iodine, 100 Gy if 103-Pd). BT arm was delivered to prostate only (145 Gy if 125-Iodine, 125 Gy if 103-Pd). The primary end point was FFP: PSA failure (American Society for Therapeutic Radiology and Oncology [ASTRO] or Phoenix definitions), local failure, distant failure, or death. RESULTS: Five hundred eighty-eight men were randomly assigned; 579 were eligible: 287 and 292 in COMBO and BT arms, respectively. The median age was 67 years; 89.1% had PSA < 10 ng/mL, 89.1% had GS 7, and 66.7% had T1 disease. There were no differences in FFP. The 5-year FFP-ASTRO was 85.6% (95% CI, 81.4 to 89.7) with COMBO compared with 82.7% (95% CI, 78.3 to 87.1) with BT (odds ratio [OR], 0.80; 95% CI, 0.51 to 1.26; Greenwood T P = .18). The 5-year FFP-Phoenix was 88.0% (95% CI, 84.2 to 91.9) with COMBO compared with 85.5% (95% CI, 81.3 to 89.6) with BT (OR, 0.80; 95% CI, 0.49 to 1.30; Greenwood T P = .19). There were no differences in the rates of genitourinary (GU) or GI acute toxicities. The 5-year cumulative incidence for late GU/GI grade 2+ toxicity is 42.8% (95% CI, 37.0 to 48.6) for COMBO compared with 25.8% (95% CI, 20.9 to 31.0) for BT (P < .0001). The 5-year cumulative incidence for late GU/GI grade 3+ toxicity is 8.2% (95% CI, 5.4 to 11.8) compared with 3.8% (95% CI, 2.0 to 6.5; P = .006). CONCLUSION: Compared with BT, COMBO did not improve FFP for prostate cancer but caused greater toxicity. BT alone can be considered as a standard treatment for men with intermediate-risk prostate cancer.
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Braquiterapia , Neoplasias de la Próstata , Braquiterapia/efectos adversos , Humanos , Neoplasias de la Próstata/radioterapia , Antígeno Prostático Específico , Dosificación Radioterapéutica , Resultado del Tratamiento , Masculino , Persona de Mediana Edad , Anciano , Anciano de 80 o más AñosRESUMEN
PURPOSE: The ongoing lack of data standardization severely undermines the potential for automated learning from the vast amount of information routinely archived in electronic health records (EHRs), radiation oncology information systems, treatment planning systems, and other cancer care and outcomes databases. We sought to create a standardized ontology for clinical data, social determinants of health, and other radiation oncology concepts and interrelationships. METHODS AND MATERIALS: The American Association of Physicists in Medicine's Big Data Science Committee was initiated in July 2019 to explore common ground from the stakeholders' collective experience of issues that typically compromise the formation of large inter- and intra-institutional databases from EHRs. The Big Data Science Committee adopted an iterative, cyclical approach to engaging stakeholders beyond its membership to optimize the integration of diverse perspectives from the community. RESULTS: We developed the Operational Ontology for Oncology (O3), which identified 42 key elements, 359 attributes, 144 value sets, and 155 relationships ranked in relative importance of clinical significance, likelihood of availability in EHRs, and the ability to modify routine clinical processes to permit aggregation. Recommendations are provided for best use and development of the O3 to 4 constituencies: device manufacturers, centers of clinical care, researchers, and professional societies. CONCLUSIONS: O3 is designed to extend and interoperate with existing global infrastructure and data science standards. The implementation of these recommendations will lower the barriers for aggregation of information that could be used to create large, representative, findable, accessible, interoperable, and reusable data sets to support the scientific objectives of grant programs. The construction of comprehensive "real-world" data sets and application of advanced analytical techniques, including artificial intelligence, holds the potential to revolutionize patient management and improve outcomes by leveraging increased access to information derived from larger, more representative data sets.
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Neoplasias , Oncología por Radiación , Humanos , Inteligencia Artificial , Consenso , Neoplasias/radioterapia , InformáticaRESUMEN
FLASH radiation therapy (FLASH-RT), delivered with ultrahigh dose rate (UHDR), may allow patients to be treated with less normal tissue toxicity for a given tumor dose compared with currently used conventional dose rate. Clinical trials are being carried out and are needed to test whether this improved therapeutic ratio can be achieved clinically. During the clinical trials, quality assurance and credentialing of equipment and participating sites, particularly pertaining to UHDR-specific aspects, will be crucial for the validity of the outcomes of such trials. This report represents an initial framework proposed by the NRG Oncology Center for Innovation in Radiation Oncology FLASH working group on quality assurance of potential UHDR clinical trials and reviews current technology gaps to overcome. An important but separate consideration is the appropriate design of trials to most effectively answer clinical and scientific questions about FLASH. This paper begins with an overview of UHDR RT delivery methods. UHDR beam delivery parameters are then covered, with a focus on electron and proton modalities. The definition and control of safe UHDR beam delivery and current and needed dosimetry technologies are reviewed and discussed. System and site credentialing for large, multi-institution trials are reviewed. Quality assurance is then discussed, and new requirements are presented for treatment system standard analysis, patient positioning, and treatment planning. The tables and figures in this paper are meant to serve as reference points as we move toward FLASH-RT clinical trial performance. Some major questions regarding FLASH-RT are discussed, and next steps in this field are proposed. FLASH-RT has potential but is associated with significant risks and complexities. We need to redefine optimization to focus not only on the dose but also on the dose rate in a manner that is robust and understandable and that can be prescribed, validated, and confirmed in real time. Robust patient safety systems and access to treatment data will be critical as FLASH-RT moves into the clinical trials.
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Habilitación Profesional , Electrones , Humanos , Instituciones de Salud , Posicionamiento del Paciente , Tecnología , Dosificación RadioterapéuticaRESUMEN
BACKGROUND: We evaluated inter-fraction penile bulb (PB) changes in prostate cancer (PCa) patients undergoing MR-guided RT in the post-radical prostatectomy (RP) setting. MATERIALS AND METHODS: 10 patients with PCa status-post RP received MR-guided RT from 2017-2019. Patients received daily setup volumetric MRI scans prior to RT delivery for alignment and target localization. Setup MRI datasets from Fx 1, Fx 19, and Fx 37 were fused for each patient based on soft tissue anatomy. The PB was contoured on each MRI. Data on volume (cc), superior/inferior positional change (cm), and mean dose (Gy) was collected. Differences were assessed by Student's t-test (sig. p<0.05). RESULTS: The mean PB volume change from Fx 1â 19 was +0.34 ± 0.34 cc (p=0.11) and from Fx 1â 37 was +0.22 ± 0.28 cc (p=0.31). The mean positional change from Fx 1â 19 was +0.08±0.26 cm (p=0.37) and from Fx 1â 37 was +0.05 ±0.25 cm (p=0.57). The mean change in mean PB dose from Fx 1â 19 was +0.19±4.86 Gy (p=0.98) and from Fx 1â 37 was -1.51â7.46 Gy (p=0.88). CONCLUSION: We present the first study evaluating inter-fraction changes to the PB during MR-guided RT. We found no clinically meaningful difference in the volume, positional change, or mean dose during RT in the post-prostatectomy setting, suggesting that PB organ motion may not need to be accounted for in radiation treatment planning.
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Disfunción Eréctil , Neoplasias de la Próstata , Humanos , Imagen por Resonancia Magnética , Masculino , Pene , Próstata/diagnóstico por imagen , Próstata/cirugía , Prostatectomía , Neoplasias de la Próstata/radioterapia , Neoplasias de la Próstata/cirugía , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por ComputadorRESUMEN
PURPOSE: External beam radiation therapy (EBRT) dose escalation has been tested in multiple prospective trials. However, the impact on patient reported outcomes (PROs) associated with higher doses of EBRT remain poorly understood. We sought to assess the differences in PROs between men treated with a dose of 70.2 Gy versus 79.2 Gy of EBRT for prostate cancer. METHODS AND MATERIALS: The phase 3 clinical trial RTOG 0126 randomized 1532 patients with prostate cancer between March 2002 and August 2008 to 79.2 Gy over 44 fractions versus 70.2 Gy over 39 fractions. Eligible patients participated in the PRO data collection. PROs completed included the International Index of Erectile Function Questionnaire (IIEF), Functional Alterations due to Changes in Elimination (FACE), and the Spitzer Quality of Life Index (SQLI). The timepoints for the IIEF were collected pre-entry and at 6, 12, and 24 months. The FACE and SQLI were collected pre-entry and at 3, 6, 12, 18, and 24 months. The impact of EBRT dose to normal structures (penile bulb, rectum, and bladder) on PROs was also examined. Mixed effects models were used to analyze trends across time. RESULTS: In total, 1144 patients completed baseline IIEF forms and of these, 56%, 64%, and 61% completed the IIEF at 6, 12, and 24 months, respectively; 1123 patients completed the FACE score at baseline and 50%, 61%, 73%, 61%, and 65% completed all 15 items for the FACE metric at timepoints of 3, 6, 12, 18, and 24 months, respectively. Erectile dysfunction at 12 months based on the single question was not significantly different between arms (38.1% for the standard dose radiation therapy arm vs 49.7% for the dose escalated radiation therapy arm; P = .051). Treatment arm (70.2 vs 79.2) had no significant impact on any PRO metrics measured across all collected domains. Comprehensive dosimetric analyses are presented and reveal multiple significant differences to regional organs at risk. CONCLUSIONS: Compliance with PRO data collection was lower than anticipated in this phase 3 trial. Examining the available data, dose escalated EBRT did not appear to be associated with any detriment to PROs across numerous prospectively collected domains. These data, notwithstanding limitations, add to our understanding of the implications of EBRT dose escalation in prostate cancer. Furthermore, these results illustrate challenges associated with PRO data collection.
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Braquiterapia , Neoplasias de la Próstata , Braquiterapia/métodos , Humanos , Masculino , Estudios Prospectivos , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/radioterapia , Calidad de Vida , Dosificación RadioterapéuticaRESUMEN
PURPOSE: To test effects of positron emission tomography (PET)-based bone marrow-sparing (BMS) image-guided intensity modulated radiation therapy (IG-IMRT) on efficacy and toxicity for patients with locoregionally advanced cervical cancer. METHODS AND MATERIALS: In an international phase II/III trial, patients with stage IB-IVA cervical carcinoma were treated with either PET-based BMS-IG-IMRT (PET-BMS-IMRT group) or standard image-guided IMRT (IMRT group), with concurrent cisplatin (40 mg/m2 weekly), followed by brachytherapy. The phase II component nonrandomly assigned patients to PET-BMS-IMRT or standard IMRT. The phase III trial randomized patients to PET-BMS-IMRT versus IMRT, with a primary endpoint of progression-free survival (PFS) but was closed early for futility. Phase III patients were analyzed separately and in combination with phase II patients, comparing acute hematologic toxicity, cisplatin delivery, PFS, overall survival (OS), and patterns of failure. In a post-hoc exploratory analysis, we investigated the association between pretreatment absolute lymphocyte count (ALC) and OS. RESULTS: In total, 101 patients were enrolled on the phase II/III trial, including 29 enrolled in phase III (PET-BMS-IMRT group: 16; IMRT group: 13) before early closure. Median follow-up was 33 months for phase III patients and 39 months for all patients. PFS and OS at 5 years for all patients were 73.6% (95% confidence interval [CI], 64.9%-84.3%) and 84% (95% CI, 76%-92.9%]), respectively. There were no differences in number of cisplatin cycles, OS, PFS, or patterns of failure between groups for the combined cohort. The incidence of acute grade ≥ 3 neutropenia was significantly lower in the PET-BMS-IMRT group compared with IMRT for randomized patients (19% vs 54%, χ2P = .048) and in the combined cohort (13% vs 35%, χ2P = .01). Patients with pretreatment ALC ≤ 1.5 k/µL had nonsignificantly worse OS on multivariable analysis (HR 2.85; 95% CI, 0.94-8.62; adjusted P = .216), compared with patients with ALC > 1.5 k/µL. There was no difference in posttreatment ALC by treatment group. CONCLUSIONS: PET-BMS-IMRT significantly reduced acute grade ≥3 neutropenia, but not treatment-related lymphopenia, compared with standard IMRT. We found no evidence that PET-BMS-IMRT affected chemotherapy delivery or long-term outcomes, and weak evidence of an association between pretreatment ALC and OS.
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Radioterapia de Intensidad Modulada , Neoplasias del Cuello Uterino , Médula Ósea/efectos de la radiación , Cisplatino/uso terapéutico , Femenino , Humanos , Tomografía de Emisión de Positrones , Radioterapia Guiada por Imagen , Radioterapia de Intensidad Modulada/efectos adversos , Radioterapia de Intensidad Modulada/métodos , Resultado del Tratamiento , Neoplasias del Cuello Uterino/diagnóstico por imagen , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/radioterapiaRESUMEN
PURPOSE: The use of prostate fiducial markers and perirectal hydrogel spacers can reduce the acute and late toxic effects associated with prostate radiation therapy. These procedures are usually performed days to weeks before simulation during a separate clinic visit to ensure resolution of procedure-related inflammation. The purpose of this study was to assess whether same-day intraprostatic fiducial marker placement, perirectal hydrogel injection, and computed tomography (CT) and magnetic resonance imaging (MRI) simulation were feasible without adversely affecting hydrogel volume, perirectal spacing, or rectal dose. If feasible, performing these procedures on the same day as simulation would expedite the start of radiation therapy, improve patient convenience, and reduce costs. METHODS AND MATERIALS: Twenty-one patients with clinically localized prostate cancer who were enrolled on a prospective clinical trial (NCT01617161) underwent same-day marker placement, hydrogel injection, and CT and MRI simulation, then underwent T2 MRI verification scans 3 to 4 weeks later. The MRI scans were fused to the CT planning scans by clinical target volumes (CTVs) to generate comparison treatment plans (70 Gy in 28 fractions). Hydrogel volume and symmetry, perirectal spacing, CTV dose, and organ-at-risk dose were evaluated. RESULTS: Verification scans occurred a mean of 24.9 ± 4.6 days after simulation and 9.3 ± 4.9 days after treatment start. Prostate volume did not change between scans (median, 67.3 ± 22.1 cm3 vs 64.1 ± 21.8 cm3; P = .64). The median hydrogel change between simulation and verification was -1.8% ± 4.5% (P = .27). No significant differences in perirectal spacing (midgland: 1.33 ± 0.45 cm vs 1.3 ± 0.7 cm; 1 cm superior: 1.25 ± 0.95 cm vs 1.43 ± 0.91 cm; 1 cm inferior: 1.16 ± 0.28 cm vs 1.41 ± 0.49 cm) were identified. No significant differences in rectal V66 (median 2.3 ± 2.18% vs 2.3 ± 2.28%; P = .99), V35 (median 14.79 ± 7.61 vs 14.67 ± 8.4; P = .73), or D1cc (65.7 ± 9.2 Gy vs 68.2 ± 9.0 Gy; P = .80) were found. All plans met CTV and organ-at-risk constraints. CONCLUSION: Same-day placement of intraprostatic fiducial markers, perirectal hydrogel, and simulation scans was feasible and did not significantly affect hydrogel volume, position, CTV coverage, or rectal dose.
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Marcadores Fiduciales , Neoplasias de la Próstata , Estudios de Factibilidad , Humanos , Hidrogeles/uso terapéutico , Imagen por Resonancia Magnética/métodos , Masculino , Estudios Prospectivos , Próstata/diagnóstico por imagen , Próstata/patología , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/radioterapia , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/métodos , Recto/efectos de la radiación , Tomografía Computarizada por Rayos XRESUMEN
BACKGROUND AND PURPOSE: Quantifying radiation dose to cardiac substructures is important for research on the etiology and prevention of complications following radiotherapy; however, segmentation of substructures is challenging. In this study we demonstrate the application of our atlas-based automatic segmentation method to breast cancer radiotherapy plans for generating radiation doses in support of late effects research. MATERIAL AND METHODS: We applied our segmentation method to contour heart substructures on the computed tomography (CT) images of 70 breast cancer patients who received external photon radiotherapy. Two cardiologists provided manual segmentation of the whole heart (WH), left/right atria, left/right ventricles, and left anterior descending artery (LAD). The automatically contours were compared with manual delineations to evaluate similarity in terms of geometry and dose. RESULTS: The mean Dice similarity coefficient between manual and automatic segmentations was 0.96 for the WH, 0.65 to 0.82 for the atria and ventricles, and 0.06 for the LAD. The mean average surface distance was 1.2 mm for the WH, 3.4 to 4.1 mm for the atria and ventricles, and 6.4 mm for the LAD. We found the dose to the cardiac substructures based on our automatic segmentation agrees with manual segmentation within expected observer variability. For left breast patients, the mean absolute difference in mean dose was 0.1 Gy for the WH, 0.2 to 0.7 Gy for the atria and ventricles, and 1.8 Gy for the LAD. For right breast patients, these values were 0.0 Gy, 0.1 to 0.4 Gy, and 0.4 Gy, respectively. CONCLUSION: Our automatic segmentation method will facilitate the development of radiotherapy prescriptive criteria for mitigating cardiovascular complications.
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PURPOSE: Accurate target definition is critical for the appropriate application of radiation therapy. In 2008, the Radiation Therapy Oncology Group (RTOG) published an international collaborative atlas to define the clinical target volume (CTV) for intensity modulated pelvic radiation therapy in the postoperative treatment of endometrial and cervical cancer. The current project is an updated consensus of CTV definitions, with removal of all references to bony landmarks and inclusion of the para-aortic and inferior obturator nodal regions. METHODS AND MATERIALS: An international consensus guideline working group discussed modifications of the current atlas and areas of controversy. A document was prepared to assist in contouring definitions. A sample case abdominopelvic computed tomographic image was made available, on which experts contoured targets. Targets were analyzed for consistency of delineation using an expectation-maximization algorithm for simultaneous truth and performance level estimation with kappa statistics as a measure of agreement between observers. RESULTS: Sixteen participants provided 13 sets of contours. Participants were asked to provide separate contours of the following areas: vaginal cuff, obturator, internal iliac, external iliac, presacral, common iliac, and para-aortic regions. There was substantial agreement for the common iliac region (sensitivity 0.71, specificity 0.981, kappa 0.64), moderate agreement in the external iliac, para-aortic, internal iliac and vaginal cuff regions (sensitivity 0.66, 0.74, 0.62, 0.59; specificity 0.989, 0.966, 0.986, 0.976; kappa 0.60, 0.58, 0.52, 0.47, respectively), and fair agreement in the presacral and obturator regions (sensitivity 0.55, 0.35; specificity 0.986, 0.988; kappa 0.36, 0.21, respectively). A 95% agreement contour was smoothed and a final contour atlas was produced according to consensus. CONCLUSIONS: Agreement among the participants was most consistent in the common iliac region and least in the presacral and obturator nodal regions. The consensus volumes formed the basis of the updated NRG/RTOG Oncology postoperative atlas. Continued patterns of recurrence research are encouraged to refine these volumes.
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Consenso , Neoplasias Endometriales/radioterapia , Guías de Práctica Clínica como Asunto , Radioterapia de Intensidad Modulada , Sociedades Médicas , Neoplasias del Cuello Uterino/radioterapia , Documentación , Neoplasias Endometriales/diagnóstico por imagen , Neoplasias Endometriales/cirugía , Femenino , Humanos , Internacionalidad , Órganos en Riesgo/efectos de la radiación , Periodo Posoperatorio , Planificación de la Radioterapia Asistida por Computador , Radioterapia de Intensidad Modulada/efectos adversos , Tomografía Computarizada por Rayos X , Neoplasias del Cuello Uterino/diagnóstico por imagen , Neoplasias del Cuello Uterino/cirugíaRESUMEN
PURPOSE: Clinical trials have described variation in radiation therapy plan quality, of which contour delineation is a key component, and linked this to inferior patient outcomes. In response, consensus guidelines have been developed to standardize contour delineation. This investigation assesses trends in contouring guidelines and examines the methodologies used to generate and deliver recommendations. METHODS AND MATERIALS: We conducted a literature search for contouring guidelines published after 1995. Of 11,124 citations, 332 were identified for full-text review to determine inclusion. We abstracted articles for the intent of the consensus process, key elements of the methodology, and mode of information delivery. A Fisher exact test was used to identify elements that differed among the guidelines generated for clinical trials and routine care. RESULTS: Overall, 142 guidelines were included, of which 16 (11%) were developed for a clinical trial. There was an increase in guideline publication over time (0 from 1995-1999 vs 65 from 2015- 2019; P = .03), particularly among recommendations for stereotactic radiation and brachytherapy. The most common disease sites were head and neck (24%), gastrointestinal (12%), and gynecologic (12%). Methods used to develop recommendations included literature review (50%) and image-based methods (45%). Panels included a median of 10 physicians (interquartile range, 7-16); 70% of panels represented multidisciplinary expertise. Guidelines developed for a clinical trial were more likely to include an image-based approach, with quantitative analysis of contours submitted by the panel members and to publish a full set of image-based recommendations (P < .005). CONCLUSIONS: This review highlights an increase in consensus contouring recommendations over time. Guidelines focus on disease sites, such as head and neck, with evidence supporting a correlation between treatment planning and patient outcomes, although variation exists in the approach to the consensus process. Elements that may improve guideline acceptance (ie, image-based consensus contour analysis) and usability (ie, inclusion of a full image set) are more common in guidelines developed for clinical trials.
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Consenso , Guías de Práctica Clínica como Asunto , Oncología por Radiación , Humanos , Oncología por Radiación/tendencias , Planificación de la Radioterapia Asistida por ComputadorRESUMEN
OBJECTIVE: To evaluate the long-term bowel-associated quality of life (QOL) in men after radiotherapy (RT) for prostate cancer with and without the use of rectal hydrogel spacer. PATIENTS AND METHODS: The patients' QOL was examined using the Expanded Prostate Cancer Index Composite (EPIC) and mean changes from baseline in EPIC domains were evaluated. A total of 215 patients from a randomised multi-institutional trial of RT, with or without hydrogel spacer, with a QOL endpoint were pooled with 165 non-randomised patients from a single institution with prospective QOL collection in patients with or without hydrogel spacer. The proportions of men with minimally important differences (MIDs) relative to pre-treatment baseline in the bowel domain were tested using repeated measure logistic models with a pre-specified threshold for clinically significant declines (≥5 equivalent to MIDx1 and ≥10 equivalent to MIDx2). RESULTS: A total of 380 men were evaluated (64% with spacer and 36% without) with QOL data being available for 199 men with >24 months of follow-up [median (range) 39.5 (31-71.4) months]. Treatment with spacer was associated with less decline in average long-term bowel QOL (89.4 for control and 94.7 for spacer) with differences at >24 months meeting the threshold of a MID difference between cohorts (bowel score difference from baseline: control = -5.1, spacer = 0.3, difference = -5.4; P < 0.001). When evaluated over time men without spacer were more likely to have MIDx1 (5 points) declines in bowel QOL (P = 0.01). At long-term follow-up MIDx1 was 36% without spacer vs 14% with spacer (P <0.001; odds ratio [OR] 3.5, 95% CI 1.7-6.9) while MIDx2 was seen in 19% vs 6% (P = 0.008; OR 3.6, 95% CI 1.4-9.1). The use of spacer was associated with less urgency with bowel movements (P = 0.002) and fewer loose stools (P = 0.009), as well as less bother with urgency (P = 0.007) and frequency of bowel movements (P = 0.009). CONCLUSIONS: In this pooled analysis of QOL after prostate RT with up to 5 years of follow-up, use of a rectal spacer was associated with preservation of bowel QOL. This QOL benefit was preserved with long-term follow-up.
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Hidrogeles , Neoplasias de la Próstata/radioterapia , Calidad de Vida , Anciano , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Radioterapia/métodos , Recto , Método Simple Ciego , Factores de TiempoRESUMEN
PURPOSE: We sought to develop a quality surveillance program for approximately 15,000 US veterans treated at the 40 radiation oncology facilities at the Veterans Affairs (VA) hospitals each year. METHODS AND MATERIALS: State-of-the-art technologies were used with the goal to improve clinical outcomes while providing the best possible care to veterans. To measure quality of care and service rendered to veterans, the Veterans Health Administration established the VA Radiation Oncology Quality Surveillance program. The program carries forward the American College of Radiology Quality Research in Radiation Oncology project methodology of assessing the wide variation in practice pattern and quality of care in radiation therapy by developing clinical quality measures (QM) used as quality indices. These QM data provide feedback to physicians by identifying areas for improvement in the process of care and identifying the adoption of evidence-based recommendations for radiation therapy. RESULTS: Disease-site expert panels organized by the American Society for Radiation Oncology (ASTRO) defined quality measures and established scoring criteria for prostate cancer (intermediate and high risk), non-small cell lung cancer (IIIA/B stage), and small cell lung cancer (limited stage) case presentations. Data elements for 1567 patients from the 40 VA radiation oncology practices were abstracted from the electronic medical records and treatment management and planning systems. Overall, the 1567 assessed cases passed 82.4% of all QM. Pass rates for QM for the 773 lung and 794 prostate cases were 78.0% and 87.2%, respectively. Marked variations, however, were noted in the pass rates for QM when tumor site, clinical pathway, or performing centers were separately examined. CONCLUSIONS: The peer-review protected VA-Radiation Oncology Surveillance program based on clinical quality measures allows providers to compare their clinical practice to peers and to make meaningful adjustments in their personal patterns of care unobtrusively.
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Instituciones Oncológicas/normas , Hospitales de Veteranos/normas , Desarrollo de Programa , Garantía de la Calidad de Atención de Salud/normas , Oncología por Radiación/normas , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Medicina Basada en la Evidencia/normas , Humanos , Neoplasias Pulmonares/radioterapia , Masculino , Revisión por Pares , Evaluación de Programas y Proyectos de Salud/normas , Neoplasias de la Próstata/radioterapia , Garantía de la Calidad de Atención de Salud/métodos , Mejoramiento de la Calidad/normas , Indicadores de Calidad de la Atención de Salud/normas , Carcinoma Pulmonar de Células Pequeñas/radioterapia , Sociedades Médicas/normas , Estados Unidos , VeteranosRESUMEN
PURPOSE: Previously a phase III trial of a hydrogel rectal spacer during prostate radiation therapy found decreased toxicity and a clinically significant improvement in bowel quality of life (QOL) at 3 years by the Expanded Prostate Cancer Index. We performed a secondary analysis to identify men less likely to benefit. METHODS AND MATERIALS: Clinical and dosimetric data for the 222 patients enrolled on the SpaceOAR phase III trial were analyzed. The volume of rectum treated to 70 Gy (V70) and the quantitative analysis of normal tissue effects in the clinic (QUANTEC) rectal dose goals were used as surrogates for clinical benefit and plan quality. Mean bowel QOL was assessed at 15 and 36 months posttreatment and the likelihood of 1× (5 points) or 2× (10 points) minimally important difference changes were assessed. RESULTS: Rectal V70 was correlated with physician scored toxicity (P = .033) and was used as a surrogate for plan quality. There was no correlation between prostate volume and rectal V70 (r = 0.077). Rectal V70 pre- and post-hydrogel was 13% and 3% for the smallest prostates (<40 mL) and 12% and 2% for the largest (>80 mL). The relative reduction in rectal V70 of 78% did not vary by prespacer V70, but the absolute reduction was greater for a higher V70. All spacer plans met the 5 QUANTEC rectal dose constraints, although 92% of control plans met all constraints. At 3 years, those not meeting all QUANTEC goals had a 15.0-point (standard deviation 15.1) decline, control patients meeting QUANTEC goals had a 4.0-point (9.5) decline, and spacer had >0.5 (7.6; P < .01). Previous surgery was not correlated with QOL (P = .8). Across prognostic groups, including age, body mass index, previous surgery, target volume, or quality of radiation plans, there was no statistically significant heterogeneity in the relative benefit of spacer in decreasing the risk of 1× or 2× the minimally important difference declines. CONCLUSIONS: There was little heterogeneity in the likelihood of spacer reducing the risk of declines in bowel QOL across clinical and dosimetric variables. Even for the >95% of plans meeting QUANTEC rectal criteria, hydrogel spacer provided potentially meaningful benefits.
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Próstata/cirugía , Neoplasias de la Próstata/cirugía , Recto/cirugía , Anciano , Anciano de 80 o más Años , Humanos , Masculino , Persona de Mediana Edad , Próstata/efectos de la radiación , Neoplasias de la Próstata/radioterapia , Recto/efectos de la radiaciónRESUMEN
INTRODUCTION: A broad range of stakeholders have called for randomised evidence on the potential clinical benefits and harms of proton therapy, a type of radiation therapy, for patients with breast cancer. Radiation therapy is an important component of curative treatment, reducing cancer recurrence and extending survival. Compared with photon therapy, the international treatment standard, proton therapy reduces incidental radiation to the heart. Our overall objective is to evaluate whether the differences between proton and photon therapy cardiac radiation dose distributions lead to meaningful reductions in cardiac morbidity and mortality after treatment for breast cancer. METHODS: We are conducting a large scale, multicentre pragmatic randomised clinical trial for patients with breast cancer who will be followed longitudinally for cardiovascular morbidity and mortality, health-related quality of life and cancer control outcomes. A total of 1278 patients with non-metastatic breast cancer will be randomly allocated to receive either photon or proton therapy. The primary outcomes are major cardiovascular events, defined as myocardial infarction, coronary revascularisation, cardiovascular death or hospitalisation for unstable angina, heart failure, valvular disease, arrhythmia or pericardial disease. Secondary endpoints are urgent or unanticipated outpatient or emergency room visits for heart failure, arrhythmia, valvular disease or pericardial disease. The Radiotherapy Comparative Effectiveness (RadComp) Clinical Events Centre will conduct centralised, blinded adjudication of primary outcome events. ETHICS AND DISSEMINATION: The RadComp trial has been approved by the institutional review boards of all participating sites. Recruitment began in February 2016. Current version of the protocol is A3, dated 08 November 2018. Dissemination plans include presentations at scientific conferences, scientific publications, stakeholder engagement efforts and presentation to the public via lay media outlets. TRIAL REGISTRATION NUMBER: NCT02603341.
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Neoplasias de la Mama/radioterapia , Fotones/uso terapéutico , Terapia de Protones , Femenino , Humanos , Ensayos Clínicos Pragmáticos como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del TratamientoRESUMEN
INTRODUCTION: NRG protocols for glioblastoma allow for clinical target volume (CTV) reductions at natural barriers; however, literature examining CTV contouring and the relevant white matter pathways is lacking. This study proposes consensus CTV guidelines, with a focus on areas of controversy while highlighting common errors in glioblastoma target delineation. METHODS: Ten academic radiation oncologists specializing in brain tumor treatment contoured CTVs on four glioblastoma cases. CTV expansions were based on NRG trial guidelines. Contour consensus was assessed and summarized by kappa statistics. A meeting was held to discuss the mathematically averaged contours and form consensus contours and recommendations. RESULTS: Contours of the cavity plus enhancement (mean kappa 0.69) and T2-FLAIR signal (mean kappa 0.74) showed moderate to substantial agreement. Experts were asked to trim off anatomic barriers while respecting pathways of spread to develop their CTVs. Submitted CTV_4600 (mean kappa 0.80) and CTV_6000 (mean kappa 0.81) contours showed substantial to near perfect agreement. Simultaneous truth and performance level estimation (STAPLE) contours were then reviewed and modified by group consensus. Anatomic trimming reduced the amount of total brain tissue planned for radiation targeting by a 13.6% (range 8.7-17.9%) mean proportional reduction. Areas for close scrutiny of target delineation were described, with accompanying recommendations. CONCLUSIONS: Consensus contouring guidelines were established based on expert contours. Careful delineation of anatomic pathways and barriers to spread can spare radiation to uninvolved tissue without compromising target coverage. Further study is necessary to accurately define optimal target volumes beyond isometric expansion techniques for individual patients.
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Neoplasias Encefálicas/radioterapia , Glioblastoma/radioterapia , Guías de Práctica Clínica como Asunto , Planificación de la Radioterapia Asistida por Computador/métodos , Neoplasias Encefálicas/diagnóstico por imagen , Protocolos Clínicos , Glioblastoma/diagnóstico por imagen , Humanos , Imagen por Resonancia MagnéticaRESUMEN
PURPOSE: With external beam radiation therapy, uncertainties in treatment planning and delivery can result in an undesirable dose distribution delivered to the patient that can compromise the benefit of treatment. Techniques including geometric margins and probabilistic optimization have been used effectively to mitigate the effects of uncertainties. However, their broad application is inconsistent and can compromise the conclusions derived from cross-technique and cross-modality comparisons. METHODS AND MATERIALS: Conventional methods to deal with treatment planning and delivery uncertainties are described, and robustness analysis is presented as a framework that is applicable across treatment techniques and modalities. RESULTS: This report identifies elements that are imperative to include when conducting a robustness analysis and describing uncertainties and their dosimetric effects. CONCLUSION: The robustness analysis approach described here is presented to promote reliable plan evaluation and dose reporting, particularly during clinical trials conducted across institutions and treatment modalities.