18F-FDG PET/CT with retrograde filling of the urinary bladder in the assessment of malignant pelvic disease

Abstract

Aim

To assess the role of PET/CT with retrograde filling of urinary bladder (RFUB) in the assessment of pelvic malignancy in patients with urothelial or gynecological tumors.

Material and methods

A retrospective longitudinal analysis based on 62 studies belonging to 52 patients was performed. All of them had a history of pelvic malignancy (29 urothelial and 23 gynecological) and 42 had undergone previous treatments. All patients underwent a standard PET/CT protocol. Inclusion criteria were radiological alterations in pelvic organs or increased urinary activity of ¹⁸F-FDG that hindered evaluation of the pelvic structures. Pathological pelvic locations were assessed as the additional value of PET/CT with RFUB. The pathologic lesions were histologically or clinically evaluated with a minimum follow-up of 12 months.

Results

Pelvic malignancy was confirmed in 33 cases, 16 of which were of urothelial origin. A total of 35/62 studies showed a pathologic PET/CT in pelvis, 4 of them were false positive and 2 false negative. In 19 cases, malignancy was detected in the bladder wall, 16 of which were true positive. No false negative was detected. Regarding standard imaging acquisition, RFUB helped to confirm or rule out bladder and/or gynecological disease in 54 cases.

Conclusion

Retrograde bladder filling is a highly recommended technique in the assessment of malignant pelvic disease, especially of bladder origin.