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Radiation pneumonitis (RP) is a common and potentially life-threatening toxicity from lung cancer radiation therapy. Data sets reporting RP rates after postoperative radiation therapy (PORT) have historically been small and with predominantly outdated field designs and radiation techniques. We examined a large cohort of patients in this context to assess the incidence and causes of RP in the modern era. We reviewed 285 patients with non-small cell lung cancer treated with PORT at our institution from May 2004 to January 2017. Complete dosimetric data and clinical records were reviewed and analyzed with grade 2 or higher RP as the endpoint (RP2+) (Common Terminology Criteria for Adverse Events v4.0). Patients were a median of 67 years old (range, 28-87), and most had pathologic stage III non-small cell lung cancer (91%) and received trimodality therapy (90%). Systematic dosimetric analyses using Dx increments of 5% and Vx increments of 2 Gy were performed to robustly evaluate dosimetric variables. Lung V 5 was also evaluated. The incidence of RP2+ after PORT was 12.6%. Dosimetric factors most associated with RP2+ were total lungV 4 (hazard ratio [HR] 1.04, P <.001) and heart V 16 (HR 1.03, P =.001). On univariate analysis, the clinical factors of age (HR 1.05, P =.006) and carboplatin chemotherapy (HR 2.32, P =.012) were correlated with RP2+. On step-up multivariate analysis, only bivariate models remained significant, including lungV 5 (HR 1.037, P <.001) and age (HR 1.052, P =.011). The incidence of RP after PORT is consistent with the literature. Factors correlated with RP include lung and heart doses, age, and carboplatin chemotherapy. These data also suggest that elderly patients may be more susceptible to lower doses of radiation to the lung. Based on these data, dose constraints to limit the risk of RP2+ to <5% in the setting of PORT include lungV 5 ≤65% in patients <65 years old and lungV 5 ≤36% in patients 65 years or older. [ABSTRACT FROM AUTHOR]

A literature review of more than 200 stereotactic body radiation therapy spine articles from the past 20 years found only a single article that provided dose-volume data and outcomes for each spinal cord of a clinical dataset: the Gibbs 2007 article (Gibbs et al, 2007 1 ), which essentially contains the first 100 stereotactic body radiation therapy (SBRT) spine treatments from Stanford University Medical Center. The dataset is modeled and compared in detail to the rest of the literature review, which found 59 dose tolerance limits for the spinal cord in 1-5 fractions. We partitioned these limits into a unified format of high-risk and low-risk dose tolerance limits. To estimate the corresponding risk level of each limit we used the Gibbs 2007 clinical spinal cord dose-volume data for 102 spinal metastases in 74 patients treated by spinal radiosurgery. In all, 50 of the patients were previously irradiated to a median dose of 40 Gy in 2-3 Gy fractions and 3 patients developed treatment-related myelopathy. These dose-volume data were digitized into the dose-volume histogram (DVH) Evaluator software tool where parameters of the probit dose-response model were fitted using the maximum likelihood approach (Jackson et al, 1995 3 ). Based on this limited dataset, for de novo cases the unified low-risk dose tolerance limits yielded an estimated risk of spinal cord injury of ≤1% in 1-5 fractions, and the high-risk limits yielded an estimated risk of ≤3%. The QUANTEC D max limits of 13 Gy in a single fraction and 20 Gy in 3 fractions had less than 1% risk estimated from this dataset, so we consider these among the low-risk limits. In the previously irradiated cohort, the estimated risk levels for 10 and 14 Gy maximum cord dose limits in 5 fractions are 0.4% and 0.6%, respectively. Longer follow-up and more patients are required to improve the risk estimates and provide more complete validation. [ABSTRACT FROM AUTHOR]

Purpose It is challenging for the radiation oncology practitioner to manage and implement the plethora of recently generated recommendations on quality and safety improvement. The online Safety Profile Assessment (SPA) tool uses an easy-to-use question-and-answer format to assess safety/quality within a clinic, provide a way to benchmark against peers, and facilitate improvement. This report describes the design and development of the SPA and experience from the first year of use. Methods Performance indicators for the SPA were derived from 4 foundations: the Agency for Healthcare Research and Quality, a review of 7 recent authoritative documents specific to radiation oncology, a recent American Association of Physicists in Medicine report on incident learning, and the American College of Radiology–American Society for Radiation Oncology accreditation system as of 2011. After pilot testing, the free-access tool was launched through the American Association of Physicists in Medicine website ( http://spa.aapm.org ) in July 2013. Questionnaire data were collected to assess the experience of users. Results The SPA tool consists of 92 indicators designed to probe safety and quality. A clinic’s performance is benchmarked against all other responses in the database, and aided by a downloadable log, quality/safety improvement strategies can be developed and tracked over time. At the time this paper was written, 279 individuals had registered, and 107 had completed the SPA. On average, the SPA required 1.3 hours to complete. The majority of respondents to the questionnaire (56%) completed the SPA with a multidisciplinary group of 4 people on average. Respondents noted that the SPA was easy or very easy to use (70%) and that they would definitely or very probably complete it again (63%). Conclusions SPA provides a straightforward means of gauging a clinic’s performance in key safety-critical areas and has been evaluated favorably by the first cohort of users. The tool has been qualified by the American Board of Radiology (ABR) as meeting the criteria for Practice Quality Improvement requirements of the ABR Maintenance of Certification Program. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: To determine bladder wall position variability during external beam radiation therapy (EBRT) for bladder cancer with intravesical fiducial markers using 2-dimensional (2D) and volumetric (3D) imaging registration. Methods and Materials: Twenty T2-4aN0-1 bladder cancer patients underwent definitive EBRT with concurrent chemotherapy between May 2001 and January 2012, and had intravesical fiducial marker placement before simulation. Computed tomographic (CT)-based treatment planning was used for an initial phase to deliver 45 Gy (1.8 Gy/fraction) to the bladder and pelvic lymphatics followed by a boost to the involved bladder wall for an additional 21.6 Gy (1.8 Gy/fraction). Orthogonal kilovoltage radiograph images (34-37 images/patient) were obtained daily, registered with digitally reconstructed radiographs from the planning scan. Translational corrections were made daily. A kilovoltage cone-beam CT (kVCBCT) was acquired weekly and its registration with the planning scan was compared with that day's 2D registration results. Results: Of 739 treatments, 6% resulted in ≥15 mm displacement in 1 or more directions and 26% resulted in ≥10 mm displacement in 1 or more directions. Based on 2D registrations, the average millimeter difference between bony registration and fiducial marker registration (BR-FMR) in the right-left (RL) (R+), anterior-posterior (AP) (A+), and superior-inferior (SI) (I+) directions were: 0.5 ± 1.0 (range, −2.0 to +3.8), 1.7 ± 4.4 (range, −8.1 to +13.5) and −3.7 ± 5.8 (range, −16.8 to +8.3), respectively. For kVCBCT registrations, the average mm difference in the RL, AP, and SI directions were 0.3 ± 2.1 (range, −2.4 to +5.1), 3.1 ± 5.9 (range, −2.9 to +13.3) and −4.8 ± 8.0 (range, −16.4 to +9.5), respectively. Conclusions: Using intravesical fiducial markers, the largest difference in bladder motion based BR-FMR differences was in the superior-inferior direction. Because fiducial markers are target surrogates, setup using bony anatomy alone can lead to target displacements up to 13.5 mm anteriorly and 16.8 mm superiorly. This confirms a 1.5-1.7 cm minimum in planning target margins. These findings suggest a significant advantage in using intravesical fiducial markers to determine daily translational corrections. [Copyright &y& Elsevier]

Purpose: Local failure continues to be a major cause of mortality in patients with inoperable non-small cell lung cancer (NSCLC) treated with radiation therapy. Dose escalation is one method of improving local control. We investigated whether high-dose radiotherapy enhances outcomes in patients with inoperable NSCLC. Materials and Methods: Eighty-two patients with inoperable NSCLC stage I-IIIB were treated with three-dimensional conformal radiotherapy to doses of ≥80 Gy. Patients were divided into 2 groups based on stage: those with stage I/II disease (55 patients) and those with stage III (IIIA or IIIB) disease (27 patients). Results: The 5-year local control and overall survival rates for the patients with stage I/II disease were 67% and 36%, respectively, with a median survival time of 41 months. For the patients with stage III disease, 5-year local control and overall survival rates were observed to be 39% and 31%, respectively, with a median survival time of 32 months. Conclusions: Our data show a favorable 5-year overall survival rate (36%) with an acceptable toxicity profile in patients with early-stage NSCLC treated to doses of ≥80 Gy using three-dimensional conformal radiotherapy. Sequential chemotherapy combined with high-dose radiation gave survival rates equivalent to those seen with concurrent chemoradiation therapy in locally advanced disease. The overall survival and local control rates observed among patients with all stages of disease are consistent with and comparable to results from other dose-escalation studies reported in the literature. [ABSTRACT FROM AUTHOR]

We present a new method of reporting the results of radiotherapy protocols. The dose-volume atlas of complication incidence is a comprehensive and unbiased summary of the dose-volume exposures and complications occurring in patients after treatment. This new tool provides clear and systematic information about the safety of regions of dose-volume exposure previously treated that can be used when considering new treatments. Actuarial and model-dependent versions of the atlas are described. By using the raw data in the appropriate forms of the atlas, logistic regression, Kaplan-Meier, and Cox proportional hazards analysis can be performed, allowing for the independent calculation of dose-volume response. The data required are simple enough that provided compatible definitions of dose, volume, and complications are used, atlases from different protocols are potentially additive, facilitating the meta-analysis of inter-interinstitutional data. If this method were adopted as a standard for reporting the outcome of treatment protocols, a potentially synergistic increase in the utility of each protocol could result. [Copyright &y& Elsevier]

Focuses on the development of intensity-modulated radiotherapy. Employment of specialized computer driven technology; Generation of dose distributions that conform to tumor targets with high-precision; Effects of the combination of intensity modulated fields on the production of custom-tailored conformal dose.

Purpose Stereotactic body radiation therapy (SBRT) is associated with excess toxicity following treatment of central lung tumors. Risk-adapted fractionation appears to have mitigated this risk, but it remains unclear whether SBRT is safe for all tumors within the central lung zone, especially those abutting the proximal bronchial tree (PBT). We investigated the dependence of toxicity on tumor proximity to PBT and whether tumors abutting the PBT had greater toxicity than other central lung tumors after SBRT. Materials and methods A total of 108 patients receiving SBRT for central lung tumors were reviewed. Patients were classified based on closest distance from tumor to PBT. Primary endpoint was SBRT-related death. Secondary endpoints were overall survival, local control, and grade 3 + pulmonary adverse events. We compared tumors abutting the PBT to nonabutting and those ≤ 1 cm and > 1 cm from PBT. Results Median follow-up was 22.7 months. Median distance from tumor to PBT was 1.78 cm. Eighty-eight tumors were primary lung and 20 were recurrent or metastatic; 23% of tumors were adenocarcinoma and 71% squamous cell. Median age was 77.5 years. Median dose was 4500 cGy in 5 fractions prescribed to the 100% isodose line. Eighteen patients had tumors abutting the PBT, 4 of whom experienced SBRT-related death. No other patients experienced death attributed to SBRT. Risk of SBRT-related death was significantly higher for tumors abutting the PBT compared with nonabutting tumors ( P < .001). Two patients with SBRT-related death received anti-vascular endothelial growth factor therapy and experienced pulmonary hemorrhage. Patients with tumors ≤ 1 cm from PBT had significantly more grade 3 + events than those with tumors > 1cm from PBT ( P = .014). Conclusions Even with risk-adapted fractionation, tumors abutting PBT are associated with a significant and differential risk of SBRT-related toxicity and death. SBRT should be used with particular caution in central-abutting tumors, especially in the context of anti-vascular endothelial growth factor therapy. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this study is to report an overview of the patterns of practice for safety-critical processes in radiation oncology clinics in the United States. Methods and materials The Safety Profile Assessment (spa.aapm.org), developed by the American Association of Physicists in Medicine, was released in July 2013. It consists of 92 indicator questions designed to assess the safety and quality of radiation oncology operations. By December 2014, 114 surveys had been completed by clinics within the United States. This database was analyzed to identify those indicators of safety and quality performance with which there was the highest degree of compliance and those indicators with which there was the least. Additionally, we assessed the extent to which key clinical activities were supported by formal policies. Voluntary post assessment surveys were completed by 86 respondents (75%). Results The mean number of patients treated per day on external beam radiation therapy devices was 64 (range, 8-600) in the clinics that responded to the survey. The average overall score for the 92 SPA indicator questions was 1.45 (range, 1.00-2.78) on a 5-point scale, with 1 being the most positive. Those indicators that were associated with the highest levels of compliance are dominated by activities that are either strongly recommended, regulated, or associated with revenue generation. Surprisingly, several of those indicators for which there was the least compliance relate to activities that are known to have contributed to serious radiation therapy misadministrations in the past. Formal policies, which are widely regarded as a backbone of a safe clinical system, were reported as lacking for some safety-critical procedures. Conclusions Although overall this analysis demonstrated reasonable performance across participating departments, several important areas for improvement were identified. The results may guide the allocation of resources both at the level of individual departments and at the professional society level. [ABSTRACT FROM AUTHOR]