Recurrence of Low-risk Non-muscle-invasive Bladder Cancer in Patients Who Did Not Receive Immediate Intravesical
Akinori Minato1, Kazumasa Jojima1, Shuki Watanabe1
1Department of Urology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan.
Background/Aim:
To reduce recurrence, immediate postoperative intravesical chemotherapy (IVC) is recommended for patients with low-risk non-muscle-invasive bladder cancer (NMIBC). This study evaluated recurrence outcomes in patients with low-risk NMIBC who did not receive immediate IVC and the potential benefit of introducing this approach.
Patients And Methods:
We retrospectively analyzed 100 patients with low-risk NMIBC who were selected from 1,845 patients who underwent transurethral resection of bladder tumor at our institution. According to international guidelines, low-risk was defined as primary, single, solitary (<3 cm), pTa, low-grade tumors without concomitant carcinoma in situ. None of the patients received immediate IVC. Tumors were re-evaluated using the 1973 and 2004/2016 World Health Organization classifications. Recurrence rates and patterns and oncological outcomes were examined.
Results:
During a median follow-up of 69 months, 45 (45%) patients experienced recurrence. The cumulative recurrence rates were 21.6% at 1 year and 46.1% at 5 years. At first recurrence, high-grade progression was observed in 12% of the patients and upstaging to pT1 in 4%. Subsequently, 2% of patients progressed to muscle-invasive disease. The 5-year recurrence rates were 38.0% and 51.6% in G1 and G2 patients, respectively (p=0.204). The 5-year cancer-specific and overall survival rates were 98.3% and 89.4%, respectively.
Conclusion:
The recurrence rate was high in low-risk patients with NMIBC who did not receive immediate IVC, and a subset of patients progressed to more aggressive disease. These findings underscore the potential benefit of introducing immediate IVC in this population.
