Delayed post-diuretic 18F-FDG PET/CT: can it help in determination of the best clinical decision for muscle invasive UB cancer patients?

Abstract

Background18F-Fluorodeoxyglucose positron emission tomography-computed tomography (18F FDG PET/CT) has been used previously in the staging of the bladder cancer patients. Its main role was to detect regional nodal metastatic spread as well as distant organ metastasis but it was limited in detection of the primary neoplasia and the local tumor recurrence in the urinary bladder due to the presence of excreted radiotracer in the urinary tract, masking the urinary bladder lesion and probably the adjacent small regional metastatic lymph nodes. The aim of this study was to highlight the efficacy of delayed post-diuretic 18F-FDG PET/CT in staging and restaging muscle invasive urinary bladder cancer (MIBC), allowing metabolic evaluation of the primary disease, in addition to detection of associated metastasis which in turn can help to determine the best clinical decision for patients. This prospective study included 35 patients with MIBC, divided into two main groups: group A (18 patients) coming for initial staging and group B (17 patients) coming for post-therapeutic assessment. All patients of both groups were analyzed by a multidisciplinary team and the clinical decisions before and after PET CT were analyzed.ResultsIn group A, 7/18 patients were upstaged with consequent changing in therapeutic management. No downstaging was reported.In group B, the response was reported in 11/17 patients where they proceeded to radical surgery with an excellent agreement to pathological findings. 3/17 patients were stationary and 3/17 patients were progressed.PET/CT helped in the determination of the best treatment decision in 68.6% of patients among both groups.ConclusionDelayed post-diuretic PET/CT imaging is an important diagnostic tool in evaluation MIBC patients, which may consequently help to determinate the best clinical decision for them.