Survival benefit associated with postoperative PET-CT before adjuvant radiotherapy or chemoradiotherapy in patients with oral squamous cell carcinoma.

The aim of this study was to analyse the impact of postoperative positron emission tomography-computed tomography (PET-CT) before adjuvant treatment in oral squamous cell carcinoma (OSCC) patients. Patients with OSCC requiring adjuvant treatment following surgery were divided retrospectively into two groups based on the implementation of PET-CT. The study endpoints were disease-specific survival (DSS) and overall survival (OS). A total of 123 patients underwent PET-CT examination; 28 had abnormal images, but only seven were confirmed to be pathologically positive. A total of 145 patients underwent computed tomography/magnetic resonance imaging (CT/MRI) examination; 20 had abnormal images, but only one was confirmed to be pathologically positive. The median OS time was 5.4 years in the PET-CT group and 4.3 years in the CT/MRI group, demonstrating a significant difference (P = 0.024). Findings were similar for the median DSS time. In patients with positive PET-CT results, the median DSS was 4.3 years and median OS was 3.5 years, and in those with negative PET-CT results, the median survival time could not be calculated as fewer than 50% of patients reached these endpoints; both differences were significant (P = 0.007 and P < 0.001). Although the false-positive rate of postoperative PET-CT is high, it improves the chance of survival through early and more frequent detection of recurrence.