Long-term Recurrence and Progression Patterns in a Contemporary Series of Patients with Carcinoma In Situ of the Bladder With or Without Associated Ta/T1 Disease Treated with Bacillus Calmette-Guérin: Implications for Risk-adapted Follow-up.

Background: Limited data are available on patients with carcinoma in situ (CIS) of the bladder managed according to current clinical practice guidelines.

Objective: To assess the patterns of recurrence, progression to muscle-invasive bladder cancer (MIBC), and upper tract urothelial carcinoma (UTUC) in patients with CIS, and to compare the effectiveness of adequate versus inadequate bacillus Calmette-Guérin (BCG) immunotherapy.

Design, Setting, And Participants: A retrospective analysis of 386 patients with CIS of the bladder with or without associated pTa/pT1 disease treated with BCG between 2008 and 2015.

Outcome Measurements And Statistical Analysis: Kaplan-Meier estimations and an inverse probability of treatment weighting (IPTW)-Cox regression were performed to compare recurrence-free survival (RFS) and progression-free survival (PFS) and UTUC incidence over time for patients who received adequate versus inadequate BCG treatment.

Results And Limitations: The median follow-up was 70.5 mo. At 5 and 10 yr, RFS was 82% and 52%, PFS was 93.6% and 75.8%, and UTUC incidence was 1.7% and 2.9%, respectively. Most recurrence (73.6%) and progression (69.1%) events occurred in the first 3 yr of follow-up, while 38.7% of UTUC incident events were recorded after 5 yr of follow-up. IPTW-Cox regression revealed that patients who received BCG treatment had a lower risk of recurrence (hazard ratio [HR] 0.21, 95% confidence interval [CI] 0.13-0.34), progression (HR 0.46, 95% CI 0.25-0.87), and UTUC incidence (HR 0.24, 95% CI 0.09-0.64). Limitations include the retrospective design and potential selection bias.

Conclusions: Patients with CIS of the bladder show a high risk of recurrence, progression, and UTUC incidence. Most of these outcomes occur during the first 3 yr of follow-up, but a significant proportion of the events occur at long-term follow-up. Although receipt of adequate BCG treatment improves outcomes, intensive and long-term surveillance may be warranted.

Patient Summary: We investigated the long-term cancer control outcomes for patients with carcinoma in situ (CIS; cancerous cells that have not spread from where they first formed) of the bladder. Patients with CIS have a high risk of cancer recurrence and progression. Treatment with bacillus Calmette-Guérin (BCG) improves outcomes.