Temporal Patterns of HNSCC Recurrence with PET/CT Monitoring

Abstract

Objective: To determine when combined 18F-fluorodeoxyglucose positron emission tomography and computed tomography (PET/CT) surveillance detects recurrence in head and neck squamous cell carcinoma (HNSCC) patients after definitive chemoradiation therapy (CRT) and to determine initial recommendations for a posttreatment PET/CT surveillance protocol. Study Design: Retrospective review. Methods and Subjects: HNSCC patients who underwent definitive CRT were evaluated for recurrence with PET/CT at 2, 5, 8, and 14 months after completing treatment. Patients were excluded if they previously failed therapy, were treated primarily with surgery, or had inadequate clinical follow-up. Recurrence was defined by histopathologic evidence of tumor. Results: Three hundred and eightyeight patients were included. Patients who did not recur were followed clinically and radiographically for a mean of 31 months (95% CI 28.5 – 33.8), median 27 months. Recurrence was identified in 110 of 388 patients (28%) from 0.3 – 56 months, median 6 months, mean 11 months (95% CI 8.5 – 12.5). Forty-seven percent of recurrences occurred within the first 6 months of surveillance, 74% within the first year, 88% within the first 2 years, 95% within the first 3 years, 98% within the first 4 years, and 100% within the first 5 years.