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

OBJECTIVES/HYPOTHESIS: 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.

STUDY DESIGN

Retrospective review.

METHODS

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).

RESULTS

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).

CONCLUSIONS

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.