Real-world Delivery and Outcomes of Intravesical BCG for Non-muscle-invasive Bladder Cancer

Intravesical bacillus Calmette-Guérin (BCG) therapy remains the standard adjuvant treatment for high-risk non-muscle-invasive bladder cancer (NMIBC), yet real-world maintenance delivery is frequently incomplete. Contemporary benchmarks that link BCG exposure patterns to clinically meaningful outcomes are needed. We evaluated real-world BCG treatment delivery and oncological outcomes in a tertiary cancer center cohort.

We retrospectively analyzed 120 consecutive patients with NMIBC who initiated intravesical BCG between June 2019 and May 2025. The institution-defined minimum BCG exposure was induction (≥5/6 instillations) plus initial maintenance (≥2/3 instillations) or re-induction (≥2/6 instillations). High-risk recurrence-free survival (HR-RFS) was defined as time from BCG initiation to high-risk NMIBC recurrence or pathological upstaging. Progression-free survival (PFS), metastasis-free survival (MFS), and overall survival (OS) were estimated using the Kaplan-Meier method.

Median age was 73 years; pT1 disease occurred in 45.8%, concomitant carcinoma in situ in 29.2%, and high-grade tumors in 98.3%. Induction (≥5/6) was delivered in 94.2% of patients, and an initial maintenance cycle (≥2 instillations in cycle 1) in 68.3%; 73.3% achieved the minimum BCG exposure. Only 2.5% completed maintenance through cycle 7. At a median follow-up of 33.5 months, median HR-RFS, PFS, MFS, and OS were not reached. One-, three-, and five-year HR-RFS rates were 91.4%, 76.7%, and 73.0%; corresponding PFS rates were 98.3%, 92.5%, and 92.5%; MFS rates were 99.2%, 93.3%, and 93.3%; and OS rates were 98.3%, 97.3%, and 86.2%.

These data provide contemporary real-world benchmarks for outcomes achieved with conventional intravesical BCG in high-risk NMIBC when long-term maintenance completion is uncommon.