For this study, 197 upper tract urothelial carcinoma patients were enrolled who received a laparoscopic radical nephroureterectomy at Chiba University Hospital and Yokohama Rosai Hospital between 2001 and 2019. The association between the various clinical factors and postoperative recurrence rates within two years were assessed. Intravesical irrigation was carried out only during surgery and by using distilled water or saline. The design for this study is as follows:
The majority of patients were male (67%) and tumors were most commonly in the renal pelvis (74.6%). There were 12.2% of patients that had multiple tumors and 56.3% of patients were <pT3. A negative resection margin was documented in 96.4% of patients. Bladder recurrence was confirmed for 79 of the 197 patients, and irrigation was carried out in 75 cases (distilled water, 49 cases; saline, 26 cases). Tumor grade (G1-2 vs G3: HR 0.51, 95% CI 0.33-0.79, p=0.0029) and irrigation (with vs. without: HR 0.25, 95% CI 0.15-0.40 p<0.0001) were related to bladder recurrence on univariate analysis. Even on multivariate analysis, both tumor grade (HR 0.56, 95% CI 0.36-0.86, p=0.0094) and irrigation (HR 0.26, 95% CI 0.15-0.41, p<0.0001) remained as independent factors. Comparison between the irrigation and non-irrigation groups showed that bladder recurrence rates were significantly lower in the irrigation groups (irrigation group vs non-irrigation group: 29.3% vs 46.7%, p=0.015). Furthermore, there was no prognostic difference between the type of irrigation (distilled water vs saline, p=0.177).
The anchoring of minute cancer cells during the perioperative period (seeding theory) have been reported as a cause of bladder carcinoma recurrence after nephroureterectomy; these recurrences may be prevented by eliminating the cancer cells that are floating in the bladder during the perioperative period. The effectiveness of postoperative intravesical instillation of chemotherapy to prevent bladder carcinoma recurrence has also been reported. Dr. Tamura concluded that intravesical irrigation with water or saline prevented early bladder recurrence in patients undergoing radical nephroureterectomy for upper tract urothelial carcinoma.
Presented by: Takaaki Tamura, MD, Chiba University Hospita, Chiba, Japan
Written by: Zachary Klaassen, MD, MSc – Assistant Professor of Urology, Georgia Cancer Center, Augusta University/Medical College of Georgia, Twitter: @zklaassen_md at the 2020 Genitourinary Cancers Symposium, ASCO GU #GU20, February 13-15, 2020, San Francisco, California