The incidence of upper tract recurrence after radical cystectomy is low ranging from 2% to 8.7% (). Risk factors for upper urinary tract recurrence have been established as: history of diffuse CIS, multifocal tumour, intramural ureteral involvement with CIS, prior ureteral tumour, prostatic involvement and urethral involvement.4–7
The ureteral FS does not appear to add any independent predictive ability over these established factors for future upper urinary tract recurrences. In addition, with its low positive predictive value, FS has a tendency to overestimate disease at the ureteral margin.
Rates of urothelial carcinoma in situ of the ureteral margin submitted for frozen section and hematoxyllin and eosin stained permanent sections
Furthermore, FS at the time of cystectomy also remains controversial in terms of its ability to enhance the prevention of upper urinary tract recurrences. The pagetoid spread of CIS makes it impossible to guarantee that a negative FS ensures that CIS is not more proximal. One study confirmed that the incidence of upper tract recurrence is higher if the initial FS was positive for CIS (16.7% vs. 2.9%).8
However, in this study by Schumacher and colleagues, the ureter was resected more proximally at the bifurcation of the common iliac vessels, which suggests that if one does perform a ureteral FS at the time of radical cystectomy, then performing the ureteral margin at the level of the iliac vessels may be of benefit.8
Other studies that have addressed the value of FS at the time of radical cystectomy question the value of this strategy in tailoring the intraoperative procedure, as segmental sectioning of the ureter until only normal urothelium is identified does not eliminate the risk of anastomotic or upper tract recurrences nor does it seem to affect survival outcomes.5,12,14
The potential shortfalls of this study were its retrospective study design, the fact that a significant number of ureters were not examined and the lack of uniformity in the management of positive frozen sections (i.e., some patients with dysplasia/ atypia were implanted without further resection). These factors would lead to selection bias. The strengths of this study are that this is one of the larger series examining FS at the time of radical cystectomy, one of the only studies to examine the sensitivity and specificity of FS of the ureters and the first to examine both the direct and indirect costs related to FS.
These data further indicate that the incidence of a ureteral abnormality and malignancy at the ureteral margin is very low in a contemporary series. The decreased incidence observed may be secondary to improved imaging of the upper tract with CT urography and better ureteroscopic instrumentation and techniques. These data also support the use of ureteral FS in patients with CIS of the bladder and/or prostatic urethra. When other risk factors associated with an increased risk for upper tract recurrences are present, such as multifocal tumour, intramural ureteral involvement with CIS, prior ureteral tumour and prostatic or urethral involvement of UC,4–7
one may also consider ureteral FS at the time of radical cystectomy. This would certainly mitigate the significant direct and indirect costs associated with FS and would not appear to place the patients at significant risk for more upper urinary tract recurrences, problems at the ureteral-intestinal anastomosis or worse survival outcomes.