Intravesical seeding of upper urinary tract urothelial carcinoma cells during nephroureterectomy: an exploratory analysis from the THPMG trial.

OBJECTIVE: The Pirarubicin Monotherapy Study Group trial was a randomized Phase II study that evaluated the efficacy of intravesical instillation of pirarubicin in the prevention of bladder recurrence after nephroureterectomy for upper urinary tract urothelial carcinoma. This study conducted further analysis of the Pirarubicin Monotherapy Study Group cohort, focusing on intravesical seeding of cancer cells. METHODS: Using the data from the Pirarubicin Monotherapy Study Group trial, bladder recurrence-free survival rates and factors associated with bladder recurrence in the control group were analyzed. RESULTS: Of 36 patients in the control group, 14 with positive urine cytology had more frequent recurrence when compared with the 22 patients with negative cytology (P = 0.004). Based on the multivariate analysis in the control group, voided urine cytology was an independent predictive factor of bladder recurrence (hazard ratio, 5.54; 95% confidence interval 1.12-27.5; P = 0.036). Of 72 patients in the Pirarubicin Monotherapy Study Group trial, 31 had positive urine cytology. Among the 31 patients, 17 patients who received pirarubicin instillation had fewer recurrences when compared with 14 patients who received control treatment (P = 0.0001). On multivariate analysis, pirarubicin instillation was an independent predictor of better recurrence-free survival rates in the patients with positive urine cytology (hazard ratio, 0.02; 95% confidence interval, 0.00-0.53; P = 0.018). Of 21 patients with bladder recurrence, 17 had recurrent tumor around cystotomy or in the bladder neck compromised by the urethral catheter, supporting the notion that tumor cells seeded in the injured urothelium. CONCLUSIONS: Intravesical instillation of pirarubicin immediately after nephroureterectomy significantly reduced the bladder recurrence rate in patients with positive voided urine cytology. The results suggest that intravesical seeding of upper urinary tract urothelial carcinoma occurs during nephroureterectomy.

Prospective randomized phase II trial of a single early intravesical instillation of pirarubicin (THP) in the prevention of bladder recurrence after nephroureterectomy for upper urinary tract urothelial carcinoma: the THP Monotherapy Study Group Trial.

PURPOSE: We evaluated the efficacy of a single early intravesical instillation of pirarubicin (THP) in the prevention of bladder recurrence after nephroureterectomy for upper urinary tract urothelial carcinoma (UUT-UC). PATIENTS AND METHODS: From December 2005 to November 2008, 77 patients clinically diagnosed with UUT-UC from 11 institutions participating in the Tohoku Urological Evidence-Based Medicine Study Group were preoperatively enrolled in this study. Patients were randomly assigned to receive or not receive a single instillation of THP (30 mg in 30 mL of saline) into the bladder within 48 hours after nephroureterectomy. Cystoscopy and urinary cytology were repeated every 3 months for 2 years or until the occurrence of first bladder recurrence. RESULTS: Seventy-two patients were evaluable for efficacy analysis, 21 of whom had a subsequent bladder recurrence. Significantly fewer patients who received THP had a recurrence compared with the control group (16.9% at 1 year and 16.9% at 2 years in the THP group v 31.8% at 1 year and 42.2% at 2 years in the control group; log-rank P = .025). No remarkable adverse events were observed in the THP-treated group. Based on multivariate analysis, THP instillation (hazard rate [HR], 0.26; 95% CI, 0.07 to 0.91; P = .035) and open surgery (HR, 0.28; 95% CI, 0.09 to 0.84; P = .024) were independently predictive of a reduced incidence of bladder recurrence. CONCLUSION: In this prospective randomized phase II study, a single intravesical instillation of THP seemed to reduce bladder recurrence after nephroureterectomy. A phase III, large-scale, multicenter study is needed to confirm these observations.