Introduction:

Sequential intravesical gemcitabine/docetaxel (Gem/Doce) has become a viable alternative to Bacillus Calmette-Guérin (BCG) for treating non-muscle-invasive bladder cancer (NMIBC). The intermediate-risk NMIBC group (IR-NMIBC) encompasses both low-grade (LG) and high-grade tumors (HG). This Study investigates the efficacy of Gem/Doce compared to BCG in treating LG and HG IR-NMIBC.

Methods:

This study included patients with IR-NMIBC who received either BCG or Gem/Doce treatment between 2013 and 2024. Maintenance regimens were administered to patients without recurrence after induction therapy. Follow-up with cystoscopy was performed according to the American Urological Association (AUA) guidelines. Kaplan-Meier analysis was used to assess recurrence-free survival (RFS) and progression-free survival (PFS) for high-grade and low-grade tumors.

Results:

Of 483 patients, 127 had IR-NMIBC, 83 had high-grade tumors, 44 received BCG, and 39 received Gem/Doce. Additionally, 44 patients had low-grade tumors, with 22 receiving BCG and 22 receiving Gem/Doce.

The median age and median follow-up for the high-grade and low-grade groups were 71 years (IQR 63 - 77), 67.5 years (57.8 - 73) (p = 0.03), and 33.6 months (IQR 14.1 – 60.7) and 28.1 months (IQR 15.8 – 42.1) (p= 0.2), respectively.

The overall 2-year any grade RFS was 52% (95% CI 43.2-62.6). The 2-year any grade RFS for the HG and LG groups was 54.8 % (95% CI 44.1-68.2) and 46.5% (95% CI 32.9-65.8) (log rank =0.093), respectively. The 2-year high-grade RFS for the HG and LG groups was 57.7% (95% CI 62.5 – 85.2) and 93.7% (95% CI 85.5 - 100) (log rank = 0.049), respectively.

The 2-year high-grade RFS for the HG group received BCG, or Gem/Doce, was 80.9% (95% CI 69.1 – 94.8) and 61.1% (95% CI 43.7 – 85.4) (log rank=0.027), respectively. The 2-year high-grade RFS for the LG group received BCG, or Gem/Doce, was 89.1% (95% CI 75.8 – 100) and 100% (95% CI 100 – 100) (log rank=0.22), respectively.

Conclusion:

BCG demonstrates improved HG RFS compared to Gem/Doce for HG IR-NMIBC, while both had comparable HG RFS in low-grade IR-NMIBC. Prospective randomized multi-center studies are needed to investigate and further personalize the intravesical adjuvant therapy regimen in the IR-NMIBC and possibly modify risk stratification groups to separate low-grade and high-grade tumors.

Funding: N/A