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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Stereotactic body radiation therapy (SBRT) to metastatic mediastinal and hilar lymphadenopathy (MHL) is challenging owing to the proximity of centrally located organs-at-risk. As limited data exist on the safety and efficacy of SBRT for MHL, a retrospective review of clinical outcomes was conducted from a large academic center.
To predict overall survival of patients receiving stereotactic body radiation therapy (SBRT) for early-stage non-small cell lung cancer (ES-NSCLC), we developed a radiomic model that integrates risk of death estimates and changes based on pre- and posttreatment computed tomography (CT) scans. We hypothesize this innovation will improve our ability to stratify patients into various oncologic outcomes with greater accuracy.
The current distribution of radiation therapy (RT) facilities in the United States is not well established. A comprehensive inventory of U.S. RT facilities was last assessed in 2005, based on data from state regulatory agencies and dosimetric quality assurance bodies. We updated this database to characterize population-level measures of geographic access to RT and analyze changes over the past 15 years.
The human commensal microbiome has been suggested to be involved in the regulation of response to anticancer therapies. However, little is known regarding changes in commensal microbes in patients with cancer during radiation therapy. We conducted a prospective, longitudinal proof-of-concept cohort study with patients with newly diagnosed nasopharyngeal carcinoma (NPC) who underwent radiation therapy-based treatment.
This retrospective cohort study aimed to determine whether adjuvant radiation therapy increases the risk of cardiac toxicity in Asian women with breast cancer, with a focus on patient-specific factors.
Our individualized functional response adaptive approach to liver stereotactic body radiation therapy (SBRT) with assessment of indocyanine green (ICG) retention at baseline and midtreatment to detect subclinical changes in liver function, permitting dose adjustment, has decreased toxicity while preserving efficacy. We hypothesized that assessment of the albumin-bilirubin (ALBI) score at baseline and midtreatment would allow for more practical identification of patients at risk for treatment-related toxicity (TRT).
To study the hypothyroidism risk after adjuvant radiation therapy (RT) and the association of different RT targets with hypothyroidism risk.
The benefit of external beam radiation therapy (EBRT) in locally advanced, well- differentiated thyroid cancer (WDTC) is uncertain. The purpose of this study is to evaluate locoregional recurrence (LRR), progression-free survival, and cause-specific survival (CSS) of patients with pT4 well-differentiated thyroid carcinoma.
Irradiation with ultrahigh dose rates (FLASH) has reemerged as a promising radiation therapy approach to effectively lower potential damage burden on normal tissue without sacrificing tumor control. However, the large number of recent FLASH studies have been conducted under vastly different experimental conditions and circumstances (ie, investigated biological endpoint, radiation quality, and environmental oxygen level), with unverified biological mechanisms of action and unexplored interplay effect of the main dependencies. To facilitate radiobiological investigation of FLASH phenomena and assessment of clinical applicability, we present an extension of the mechanistic radiobiological model “UNified and VERSatile bio response Engine” (UNIVERSE).
To report the long-term outcome of patients with prostate cancer treated with external beam radiation therapy and high dose rate (HDR) brachytherapy from a prospective multi-institutional trial conducted by NRG Oncology/RTOG.
Definitive, nonsurgical management of gynecologic malignancies involves external beam radiation therapy (EBRT) and/or brachytherapy (BT). Summation of the cumulative dose is critical to assess the total biologic effective dose to targets and organs at risk. Cumulative dose calculation from EBRT and BT can be performed with or without image registration (IR) and biologic dose summation. Among these dose summation strategies, linear addition of dose-volume histogram (DVH) parameters without IR is the global standard for composite dose reporting. This approach stems from an era without image guidance and simple external beam and brachytherapy treatment approaches. With technological advances, EBRT and high-dose-rate BT have evolved to allow for volume-based treatment planning and delivery. Modern conformal therapeutic radiation involves volumetric or intensity modulated EBRT, capable of simultaneously treating multiple targets at different specified dose levels. Therefore, given the complexity of modern radiation treatment, the linear addition of DVH parameters from EBRT and high-dose-rate BT is challenging to represent the combined dose distribution. Deformable image registration (DIR) between EBRT and image guided brachytherapy (IGBT) data sets may provide a more nuanced calculation of multimodal dose accumulation. However, DIR is still nascent in this regard, and needs further development for accuracy and efficiency for clinical use. Biologic dose summation can combine physical dose maps from EBRT and each IGBT fraction, thereby generating a composite DVH from the biologic effective dose. However, accurate radiobiologic parameters are tissue-dependent and not well characterized. A combination of voxel-based DIR and biologic weighted dose maps may be the best approximation of dose accumulation but remains invalidated. The purpose of this report is to review dose summation strategies for EBRT and BT, including conventional equivalent dose in 2-Gy fractions dose summation without image registration, physical dose summation using 3-dimensional rigid IR and DIR, and biologic dose summation. We also provide general clinical workflows for IGBT with a focus on cervical cancer.
Acute esophagitis (AE) is a common dose-limiting toxicity in radiation therapy of locally advanced non-small cell lung cancer (LA-NSCLC). We developed an early AE prediction model from weekly accumulated esophagus dose and its associated local volumetric change.
The effects of thoracic radiation therapy (RT) on physical functioning and quality of life (QoL) are incompletely defined. We determined the associations between thoracic RT dose volume metrics, physical activity, and QoL in patients with cancer.
Treatment noncompletion may occur with radiation therapy (RT), especially with protracted treatment courses such as RT for prostate cancer, and may affect the efficacy of RT. For men with localized prostate cancer managed with primary RT, we evaluated associations between rates of treatment noncompletion and RT fractionation schedules.
Androgen deprivation therapy (ADT) is often used as adjuvant treatment with radiation therapy (RT) for intermediate-risk prostate cancer. ADT is associated with multiple side effects, including weight gain, loss of libido, and hot flashes. In contrast, antiandrogen monotherapy has been generally better tolerated. This study aimed to assess the effectiveness of enzalutamide (an antiandrogen) monotherapy with RT for the treatment of intermediate-risk prostate cancer.
An overview of common approaches used to assess a dose response for radiation therapy–associated endpoints is presented, using lung toxicity data sets analyzed as a part of the High Dose per Fraction, Hypofractionated Treatment Effects in the Clinic effort as an example. Each component presented (eg, data-driven analysis, dose-response analysis, and calculating uncertainties on model prediction) is addressed using established approaches. Specifically, the maximum likelihood method was used to calculate best parameter values of the commonly used logistic model, the profile-likelihood to calculate confidence intervals on model parameters, and the likelihood ratio to determine whether the observed data fit is statistically significant. The bootstrap method was used to calculate confidence intervals for model predictions. Correlated behavior of model parameters and implication for interpreting dose response are discussed.
Our previous findings have identified vitronectin (VTN) as a potential biomarker for radiation pneumonitis (RP) through proteomics and molecular mechanism studies. In a recent study, we further explored associations of plasma level and single nucleotide polymorphisms of VTN with the risk of RP in patients with lung cancer receiving radiation therapy.
Proton therapy is a limited resource that is not available to all patients who may benefit from it. We investigated combined proton-photon treatments, in which some fractions are delivered with protons and the remaining fractions with photons, as an approach to maximize the benefit of limited proton therapy resources at a population level.