Research published in the December issue of the Journal of Nuclear Medicine suggests that 18F-FDG PET is a suitable routine posttreatment surveillance tool in oral and oropharyngeal squamous cell carcinoma (SCC) patients, between three and six months after treatment and could detect malignancy not detected by regular follow up.
Christiaan A. Krabbe, MD, and colleagues at the department of oral and maxillofacial surgery at University Medical Center Groningen in the Netherlands, evaluated the role and timing of serial 18F-FDG PET scans for detecting early locoregional recurrence, distant metastases, and second primary tumors in patients treated for advanced SCC in the oral cavity or oropharynx during the first year after completion of their curative treatment.
The study included 48 consecutive patients with SCC in the oral cavity or oropharynx after completing their initial therapy with curative intent.
Prospective follow up of the participants was two-fold: regular follow-up (history and physical exam) and serial 18F-FDG PET scans at three, six, nine and 12 months after initial treatment, according to Krabbe and colleagues.
“18F-FDG PET accounted for a change in diagnostics or treatment in 63 percent of the patients and regular follow-up in 25 percent of the patients. For the three and six months posttherapy results combined, 18F-FDG PET detected malignancy in 16 of the 18 patients,” said Krabbe.
The researchers found that 18F-FDG PET showed 100 percent sensitivity, 43 percent specificity, 51 percent positive predictive value and 100 percent negative predictive value while regular follow up showed zero percent sensitivity, 60 percent sensitivity, zero percent positive predictive value and 50 percent negative predictive value.