Low-grade Urothelial Carcinoma Recurs at a Tempo that Naturally Accelerates Over Time

To investigate the cadence of recurrence in patients with low grade intermediate-risk non-muscle invasive bladder cancer (LG IR-NMIBC) based on clinical determinants. We aim to describe patterns in rates of recurrence to better inform surveillance regimens for this chronic, burdensome, and costly disease.

Using baseline and follow-up data from participants in the West Midlands' (United Kingdom, UK) Bladder Cancer Prognosis Programme (BCPP), we assessed overall recurrence rate and recurrence-free intervals throughout the follow-up period for IR-NMIBC participants. Recurrence-free intervals were calculated using the Kaplan-Meier method.

We identified 379 patients with G1/G2 pTa tumors classified as intermediate risk. Median age was 70 and 284/379 (75%) were male. The median follow-up time was 4.2 years (95% CI: 3.9-4.8). After 5 years of follow-up, 53% of patients had at least one recurrence. One-year recurrence-free survival (RFS) was 75% and 4-year RFS was 50%. The median time to or between 1st, 2nd, 3rd, 4th, and 5th sequential recurrences was 49, 19, 12, 14, and 10 months, respectively.

Over half of patients with IR-NMIBC are destined to recur. Our data suggest that a subset of patients experience acceleration of recurrence over time and that this acceleration may serve as a potential kinetic biomarker for these individuals that could inform surveillance intervals and future treatment strategies.