Prophylactic intravesical chemotherapy decreases bladder tumor recurrence after nephroureterectomy for primary upper tract urothelial carcinoma: A systematic review and meta-analysis.

Purpose: A high incidence of bladder tumor (BT) occurs after radical nephroureterectomy (NU) for primary upper tract urothelial carcinoma (UTUC). Although some studies have shown that prophylactic intravesical chemotherapy could prevent BT recurrence, it has not become standard practice at this stage. The purpose of this study was to evaluate the effect of intravesical instillation chemotherapy in preventing BT recurrence in patients with primary UTUC after nephroureterectomy.

Methods: A comprehensive literature search was performed in July 2014 using the Medline, Embase, and Cochrane Library databases, as well as the China National Knowledge Infrastructure and Wanfang Data. All clinical trials compared the effect of prophylactic intravesical chemotherapy after radical NU for primary UTUC. Analysis was performed using the Stata 12.0 SE software.

Results: Eight trials were analyzed with a total of 979 patients including 521 patients receiving intravesical chemotherapy instillation and 458 without instillation. The BT incidence rate was 125 out of 521 patients (24.0%) with intravesical instillation chemotherapy after NU, and 169 out of 458 patients (36.9%) without intravesical chemotherapy after NU. Compared with those who didn't receive instillation, the pooled odds ratio (OR) of BT recurrence was 0.45 (95% confidence interval/CI 0.34-0.61, p<0.0001) in instillation patients. In the sub-analyses, the OR of single instillation was similar to repeated instillations (0.48 and 0.42). The OR of beginning the first instillation within 24 hrs, 48 hrs and 2 weeks was 0.34, 0.48 and 0.46, respectively.

Conclusions: This systematic review demonstrates that prophylactic intravesical instillation chemotherapy can prevent BT recurrence in primary UTUC patients after NU. It also suggests that single instillation may have a similar effect to repeated instillations. The first instillation beginning within 24 hrs seems to show lower BT recurrence than at 48 hrs or 2 weeks. However, given that some limitations exist, well-designed randomized controlled trials are needed to further evaluate these results.