Ureteral stenting ups risk of metachronous upper tract urothelial carcinoma in bladder cancer

Treatment with ureteral stenting in patients with bladder cancer, either to protect the ureteral orifice and prevent obstruction or to decompress established upper urinary tract (UUT) obstruction, appears to increase the risk of developing metachronous upper tract urothelial carcinoma (UTUC) compared with no stenting, results of a study have shown.

“Given this risk, it is recommended that prophylactic stenting after resection of tumours involving the orifice should be avoided,” the researchers said.

“On the other hand, as a therapeutic option in cases of hydronephrosis, drainage is imperative and should be performed with either ureteral stenting or percutaneous nephrostomy, considering the similar impact of both on the risk of metachronous UTUC,” they added.

A systematic review and meta-analysis was conducted on studies comparing ureteral stenting vs nephrostomy or no drainage regarding the risk of metachronous UTUC. The researchers identified records through database searches and sources of grey literature up to October 2020. Five studies involving 3,309 participants overall were included.

Ureteral stents were placed in a total of 278 patients, among whom 20 (7.2 percent) developed metachronous UTUC; while 131 were treated with nephrostomy, of which three (2.3 percent) cases of metachronous UTUC appeared. [J Urol 2021;205:956-966]

Ureteral stenting was associated with a higher risk of metachronous UTUC compared to no stents (odds ratio [OR], 3.49, 95 percent confidence interval [CI], 1.43–8.48; I², 52 percent) and no UUT drainage (OR, 3.37, 95 percent CI, 1.49–7.63; I², 45 percent).

No difference was noted in metachronous UTUC between stent and nephrostomy (OR, 3.07, 95 percent CI, 0.41–22.98; I², 54 percent). There was also no difference seen for patients with hydronephrosis. However, the level of evidence for all measures was deemed low.

“There are certainly quality of life issues related to both management options. Ureteral stents cause more lower urinary tract symptoms compared to percutaneous nephrostomy. Bladder irritation, dysuria, and urgency are the more common and lead to reduced quality of life in most patients,” the researchers said. [Eur Urol 2001;39:695-701; J Urol 2003;169:1065-1069]

Percutaneous nephrostomy, on the other end, triggers local pain and discomfort. It is also associated with poor personal hygiene and self-care difficulties. In contrast to ureteral stent, these local symptoms improve shortly after the procedure. Nonetheless, percutaneous nephrostomy is more invasive and may lead to more complications. [J Endourol 2010;24:129-142; J Endourol 2019 33:777-786]

“It should be stressed that multiple factors have been associated with UUT recurrence in patients with bladder cancer,” the researchers said.

Previous studies reported the following factors associated with an increased risk of UTUC after bladder cancer diagnosis: higher stage or grade, larger tumour diameter, frequency of tumour recurrence, multifocality, concomitant carcinoma in situ, ureteral orifice involvement, previous UUT manipulations, stent indwelling time, prostatic urethra or lymphovascular invasion, treatment with intravesical bacillu Calmette-Guérin, hypronephrosis, ageing, smoking, and vesicoureteral reflux. [Eur Urol 2007;51:690-698; J Urol 1996;156:1286-1287; http://uroweb.org/guideline/upper-urinary-tract-urothelial-cell-carcinoma/]

“Since many of these parameters were not reported in the included studies, randomized controlled trials or well-designed observational studies could theoretically adjust for these potential confounders,” the researchers said.