International journal of radiation oncology, biology, physics
-
Int. J. Radiat. Oncol. Biol. Phys. · Sep 2017
Comparative StudyVariabilities of Magnetic Resonance Imaging-, Computed Tomography-, and Positron Emission Tomography-Computed Tomography-Based Tumor and Lymph Node Delineations for Lung Cancer Radiation Therapy Planning.
To investigate interobserver delineation variability for gross tumor volumes of primary lung tumors and associated pathologic lymph nodes using magnetic resonance imaging (MRI), and to compare the results with computed tomography (CT) alone- and positron emission tomography (PET)-CT-based delineations. ⋯ Although MRI-based contouring showed overall larger variability than PET-CT, contouring variability depended on the interface type and was not significantly different between modalities, despite the limited observer experience with MRI. Multimodality imaging and combining different imaging characteristics might be the best approach to define the tumor volume most accurately.
-
Int. J. Radiat. Oncol. Biol. Phys. · Sep 2017
Domestic Job Shortage or Job Maldistribution? A Geographic Analysis of the Current Radiation Oncology Job Market.
To examine whether permanent radiation oncologist (RO) employment opportunities vary based on geography. ⋯ This study presents a quantitative analysis of the RO job market. We found a disproportionately small number of opportunities compared with graduates trained in the Northeast, as well as a significant regional imbalance of academic versus nonacademic jobs. Long-term monitoring is required to confirm these results.
-
Int. J. Radiat. Oncol. Biol. Phys. · Sep 2017
Evaluating Which Dose-Function Metrics Are Most Critical for Functional-Guided Radiation Therapy.
Four-dimensional (4D) computed tomography (CT) ventilation imaging is increasingly being used to calculate lung ventilation and implement functional-guided radiation therapy in clinical trials. There has been little exhaustive work evaluating which dose-function metrics should be used for treatment planning and plan evaluation. The purpose of our study was to evaluate which dose-function metrics best predict for radiation pneumonitis (RP). ⋯ A full range of dose-function metrics and functional thresholds was examined. The calculated AUC values for the most predictive functional models occupied a narrow range (0.66-0.70), and all showed notable improvements over AUC from traditional lung dose metrics (0.55). Identifying the combinations most predictive of grade 3+ RP provides valuable data to inform the functional-guided radiation therapy process.
-
Int. J. Radiat. Oncol. Biol. Phys. · Sep 2017
Lymphocyte Nadir and Esophageal Cancer Survival Outcomes After Chemoradiation Therapy.
Host immunity may affect the outcome in patients with esophageal cancer. We sought to identify factors that influenced absolute lymphocyte count (ALC) nadir during chemoradiation therapy (CRT) for esophageal cancer (EC) and looked for clinically relevant associations with survival. ⋯ G4 nadir during CRT for EC was associated with poor outcomes, suggesting a role of host immunity in disease control. This observation provides a rationale to prospectively test chemotherapeutic and radiation treatment strategies that may have a lower impact on host immunity.