Narrow interval dual phase 18F-FDG PET/CT: A practical approach for distinguishing tumor recurrence from radiation necrosis in brain metastasis.

Purpose of our research is to demonstrate efficacy of narrow interval dual phase [18F]-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) imaging in distinguishing tumor recurrence (TR) from radiation necrosis (RN) in patients treated for brain metastases. 35 consecutive patients (22 female, 13 male) with various cancer subtypes, lesion size > 1.0 cm3, and suspected recurrence on brain magnetic resonance imaging (MRI) underwent narrow interval dual phase FDG-PET/CT (30 and 90 min after tracer injection).

Risk factors for symptomatic radiation pneumonitis after stereotactic body radiation therapy (SBRT) in patients with non-small cell lung cancer.

Background And Purpose: Radiation pneumonitis (RP) can be a potential fatal toxicity of stereotactic body radiation therapy (SBRT) for medically inoperable non-small cell lung cancer (NSCLC). This study aimed to examine the risk factors that predict RP and explore dosimetric tolerance for safe practice in a large institutional series of NSCLC patients.

Materials And Methods: Patients with early-stage and locally recurrent NSCLC who received lung SBRT between 2002 and 2015 formed the study population.

Coverage-based treatment planning to accommodate deformable organ variations in prostate cancer treatment.

Purpose: To compare two coverage-based planning (CP) techniques with standard fixed margin-based planning (FM), considering the dosimetric impact of interfraction deformable organ motion exclusively for high-risk prostate treatments.

Methods: Nineteen prostate cancer patients with 8-13 prostate CT images of each patient were used to model patient-specific interfraction deformable organ changes. The model was based on the principal component analysis (PCA) method and was used to predict the patient geometries for virtual treatment course simulation.