Ozturk K, et al. - An overall 80 patients who underwent a total of 197 posttreatment whole-body ¹⁸F-FDG PET/CT examinations for sinonasal malignancy were retrospectively investigated by the researchers in order to evaluate the ideal timing of posttreatment whole-body ¹⁸F-FDG PET/CT examination as routine surveillance to ascertain local recurrence, lymph node metastasis, and distant metastasis of sinonasal malignancies and to examine the impact of ¹⁸F-FDG PET/CT on survival. The negative predictive value and positive predictive value of the ¹⁸F-FDG PET/CT examinations to prognosticate overall recurrence in 1–3 months and > 18 months were greater than for recurrence detection in < 1 month, 3–6 months, 6–12 months, and 12–18 months, taking the time intervals of posttreatment ¹⁸F-FDG PET/CT scans into account. Positive conclusions on ¹⁸F-FDG PET/CT scans were also independent predictors of poorer overall survival. Thus, whole-body ¹⁸F-FDG PET/CT was concluded as capable of recognizing recurrences after treatment, using an optimal time interval for scanning of 1–3 months and > 18 months following therapy.