The purpose of this study was to assess the efficiency of fluorine-18 fluoro-2-deoxyglucose (FDG) positron emission tomography (PET) in the characterisation and primary staging of suspicious renal masses, in comparison with computed tomography, the current standard imaging modality. Fifty-three FDG PET studies were performed within the framework of a prospective study: 35 for both characterisation and staging of a suspicious mass, and 18 for staging early after surgical removal of a renal cancer. In the characterisation of renal masses, a high rate of false negative results was observed, leading to a sensitivity, specificity and accuracy of 47%, 80% and 51% respectively, versus 97%, 0/5 and 83% respectively for CT. FDG PET detected all the sites of distant metastasis revealed by CT, as well as eight additional metastatic sites, leading to an accuracy of 94% versus 89% for CT. However, 36/53 patients (68%) did not have any distant metastasis on either CT or on PET. All but one of these patients had a low Fuhrman histological grade and a limited local stage (< or =pT2). We conclude that FDG PET does not offer any advantage over CT for the characterisation of renal masses but that it appears to be an efficient tool for the detection of distant metastasis in renal cancer. However, our data suggest that a selection process could be implemented to determine which patients should undergo PET. FDG PET could be performed in the event of a solitary metastasis or doubtful images on CT. Selection could also be based on adverse histological findings from nephrectomy specimens in order to perform staging early after nephrectomy.

No abstract

The urachus is an embryonic remnant resulting from involution of the allantoic duct and the ventral cloaca. Attaching the bladder dome to the umbilicus, this duct becomes progressively obliterated during fetal life. It may subsequently persist as different variants after birth, some regarded as normal, others as pathologic, due to incomplete closure. Six pediatric cases are reported here, and the literature on the embryology and anatomic basis of the duct is discussed. The urachus is present in nearly 100% of children at birth, with several possible shapes: tubular, fusiform or funnel. It gradually regresses and is found in only a third of adults. Its length varies from 1 to 15 cm. In our series 6 patients showed defective closure of the duct, including 3 with complete patency, 1 cyst, 1 diverticulum and 1 external sinus. Although rare, congenital pathology of the urachus requires a sound knowledge of the anatomy and embryology to distinguish normal forms from those subject to complications. It should be suspected with any lesion in the umbilical region and the appropriate treatment instituted.

Postprostatectomy incontinence remains a disabling condition. Sphincter injury, detrusor instability, and decreased bladder compliance have been previously reported as major factors. The aim of this study was to evaluate the urethral sphincter intrinsic component, which may provide passive continence. A urodynamic evaluation was performed in 20 patients undergoing a radical retropubic prostatectomy in the preoperative period and 3 months after surgery. Patients with disabled urinary incontinence underwent a new urodynamic evaluation 6 months later. The urethral pressure profile was measured just before, then 10, 20, and 30 minutes after the injection of 0.5 mg/kg moxisylyte chlorhydrate, an alpha adrenergic blocker. Three different pressure components were defined in urethral sphincter capacity: baseline, adrenergic, and voluntary. A postoperative intrinsic urethral sphincter pressure component was found in 17 patients and its value was under 6 cm H(2)O in five cases of severe incontinence. No significant difference was observed for these patients on urethral profile components 6 months later. In contrast, in cases of significant intrinsic component value, no incontinence was observed in most patients. Passive continence after radical prostatectomy should be a matter of concern and may also explain paradoxical incontinence, despite high voluntary urethral pressure obtained after reeducation. A follow-up evaluation of the intrinsic sphincter component is suggested, by using an alpha receptor blockage test during urodynamic studies in the management of patients with postprostatectomy incontinence.