CT and FDG-PET radiologic biomarkers in p16+ oropharyngeal squamous cell carcinoma patients treated with definitive chemoradiotherapy.

CONCLUSIONS: In the largest study to date of uniformly treated patients with CRT to evaluate both pretreatment CT and FDG-PET, radiographic biomarkers were significantly associated with TTLRF, TTDMF and OS among patients with p16+ OPSCC treated with CRT. CT metrics performed best to predict TTDMF, while FDG-PET metrics showed improved prediction for LRRFS. These metrics may help identify candidates for treatment intensification or de-escalation of therapy. STATEMENT OF TRANSLATIONAL RELEVANCE: Pre-treatment imaging features from standard-of-care PET/CT imaging show promise for predicting long-term outcomes following HPV-associated oropharynx cancer (HPV-OPC) therapy. This study comprehensively characterizes qualitative and quantitative pre-treatment imaging metrics associated with time to pattern-specific failure in a cohort of 266 patients treated uniformly with definitive chemoradiation. Multivariate analysis (MVA) for time to loco-regional failure (TTLRF), time to distant metastatic failure (TTDMF), and overall survival (OS) was performed. FDG-PET metrics outperformed CT and clinical metrics for TTLRF. CT radiographic extranodal extension, positive retropharyngeal nodes, and stage strongly predicted TTDMF (combined C-index=0.84, log rank p<0.001). Number of smoking pack-years complemented clinical and imaging features only in patients without radiographic extranodal extension or positive retropharyngeal nodes. Time to pattern-specific failure is important for gu...
Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology - Category: Radiology Authors: Tags: Radiother Oncol Source Type: research