Long-term Recurrence Rates of Low-risk Non-muscle-invasive Bladder Cancer-How Long Is Cystoscopic Surveillance Necessary?

BACKGROUND

While low-risk non-muscle-invasive bladder cancer (LR-NMIBC) has a low propensity to progress, the risk of recurrence remains high (50% within 4 yr). Guidelines recommend cystoscopic surveillance after resection, but the necessary duration of follow-up is debated.

OBJECTIVE

To determine the risk of recurrence beyond 5 yr after diagnosis in patients with LR-NMIBC, and to identify risk factors of recurrence.

DESIGN, SETTING, AND PARTICIPANTS: In this multicenter retrospective observational study, patients who received their first transurethral bladder tumor resection before 2016 for LR-NMIBC were included. Low risk was defined as a primary, solitary, low grade, Ta bladder tumor measuring <3 cm.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary endpoint was determination of the recurrence rates at 1, 2, and 5 yr. The secondary endpoints included overall recurrence-free survival (RFS) and high-risk RFS. A univariate analysis and multivariable logistic regression were performed to assess the risk factors for recurrence over the study period.

RESULTS AND LIMITATIONS

The median age of the 577 patients was 70.9 yr, and 126 (21.8%) patients were female. The median follow-up was 69.6 (interquartile range: 58.4) mo, and recurrence was observed in 236 (40.9%) patients. The 1-, 2-, and 5-yr RFS rates were 81.6% (95% confidence interval 78.4-84.9), 72.4% (68.7-76.3), and 59.2% (55-63.8), respectively. Recurrence after 5 yr was observed in 13.1% (28/213). High-risk recurrence, defined as the first recurrence of a high-grade and/or ≥T1 tumor, occurred in 6.2% (36/579) overall and 2.8% (6/213) after 5 yr. The lack of a single postoperative dose of chemotherapy and tumor size >2 cm were prognostic factors of recurrence.

CONCLUSIONS

The risk of recurrence in patients with LR-NMIBC decreases progressively after the 1st year and remains low beyond 5 yr. Discontinuation of endoscopic surveillance after 5 yr in patients with LR-NMIBC can be discussed. Treatment with postoperative chemotherapy and tumor size <2 cm may be relevant variables to identify patients who will benefit from cystoscopic follow-up as short as 12 mo.

PATIENT SUMMARY

In this study, we observed that 13% of patients who did not have a recurrence during the first 5 yr following the diagnosis of low-risk non-muscle-invasive bladder cancer will recur after this time point. Discontinuation of cystoscopic surveillance can be discussed after 5 yr in these patients.