Clinical value of [F-18]-Fluorodeoxyglucose PET/CT in locally recurrent and metastatic bladder transitional cell carcinoma

Objectives The utility of FDG PET in locally recurrent bladder transitional cell carcinoma has not been fully explored, due to interference of urine activity with visualization of locally recurrent cancer. The purpose of the present study is to evaluate clinical value of 18F-FDG PET/CT in locally recurrent and metastatic bladder cancer.

Methods 147 patients with bladder cancer underwent 18F-FDG PET/CT for follow-up (106 males and 41 females; median age, 65.8 years). Patients were hydrated with oral intake of water and diuretics was administered before image acquisition. Contrast enhanced CT performed within 2 months were evaluated for comparison. Local recurrence was defined enhancing lesion on CT scan with matched FDG uptake on 18F-FDG PET/CT. Urine cytology or cystoscopy was assessed to confirm local recurrence. To confirm distant metastasis, following imaging studies including CT, MRI and 18F-FDG PET/CT were evaluated.

Results 39 patients were confirmed tumor recurrence. 25 of them had local recurrence, and 17 had distant metastasis. Overall sensitivity and specificity of CT scan was 77.3% and 95.1% in local recurrence. Overall sensitivity and specificity of CT scan with FDG PET was 82.1% and 95.8% in detecting distant metastasis FDG PET found all the metastatic lesions that could not be found in conventional enhanced CT. Metastatic sites were lung, bone, adrenal gland, pancreas and liver. 5 cases of other secondary primary cancers were incidentally found on FDG PET scans.

Conclusions 18F-FDG PET with CT showed higher sensitivity and specificity than CT scan alone for detecting locally recurrent bladder cancer. Also, whole body FDG PET scan had ability to find distant metastasis and other second primary malignancy