Prospective Study of PET/MRI Tumor Response During Chemoradiotherapy for Patients With Low-risk and Intermediate-risk p16-positive Oropharynx Cancer

The objective of this study was to examine tumor response with positron emission tomography (PET)/magnetic resonance imaging (MRI) during chemoradiotherapy as a predictor of outcome in patients with p16-positive oropharynx cancer. Materials and Methods: Patients with p16-positive oropharynx cancer were treated with chemoradiotherapy. Low-risk (LR) disease was defined as T1-T3 and N0-2b and ≤10 pack-years and intermediate-risk (IR) disease as T4 or N2c-3 or>10 pack-years. Patients underwent a PET/MRI scan pretreatment and at fraction 10. Change in value of imaging means were analyzed by analysis of variance. K-means clustering with Euclidean distance functions were used for patient clustering. Silhouette width was used to determine the optimal number of clusters. Linear regression was performed on all radiographic metrics using patient and disease characteristics. Results: Twenty-four patients were enrolled with 7 LR and 11 IR patients available for analysis. Pretreatment imaging characteristics between LR and IR patients were similar. Patients with LR disease exhibited a larger reduction in maximum standardized uptake value (SUV) compared with IR patients (P
Source: American Journal of Clinical Oncology - Category: Cancer & Oncology Tags: Original Articles: Head and Neck Source Type: research