Predictive accuracy of first post-treatment PET/CT in HPV-related oropharyngeal squamous cell carcinoma.

Abstract

To determine whether the result of first posttreatment positron emission tomography and computed tomography (PET/CT) is predictive of outcome in patients with oropharyngeal squamous cell carcinoma (OPSCC), and whether PET/CT accuracy is affected by human papillomavirus (HPV) status. Retrospective review. Demographic, clinical, and radiographic data were available for 61 patients with OPSCC, treated in 2004 to 2012 at a single tertiary academic referral center, with at least one baseline and one posttreatment PET/CT. Clinical follow-up was obtained every 3 months thereafter. The median follow-up time was 36 months (range 3-100 months). Of 61 patients, 48 (79%) had negative first posttreatment PET/CT results; and overall, 18 of the 61 patients (30%) recurred. All accuracy measures for PET/CT were higher in HPV-positive patients, including a 93% negative predictive value (NPV). Patients with positive PET/CT results had poorer survival on Kaplan-Meier analyses. On multivariate analysis of factors predictive of recurrence, two parameters were significant: HPV status (P = 0.0046) and PET/CT result (P <0.0001). A negative first posttreatment PET/CT result is associated with better prognosis and rare recurrence, especially in patients with HPV-positive status. Less frequent radiologic surveillance is warranted in patients with HPV-positive OPSCC and a negative first posttreatment PET/CT scan.