Introduction:

 Sequential intravesical gemcitabine/docetaxel (Gem/Doce) has emerged as a potential alternative to Bacillus Calmette-Guérin (BCG) for the treatment of non-muscle-invasive bladder cancer (NMIBC). We seek to determine the comparative effectiveness of BCG and Gem/Doce for patients in the intermediate-risk group (IR) composed mainly of Ta high-grade (TaHG) disease.

Methods:

Patients with IR-NMIBC who received either BCG or Gem/Doce during 2013 – 2024 were included. After induction therapy, maintenance regimens were offered to patients with no evidence of recurrence. Routine surveillance with cystoscopy was performed according to the American Urological Association (AUA) guidelines. High-grade and any-grade recurrence-free survival (RFS), and progression-free survival (PFS) were assessed with the Kaplan-Meier method. Cox regression analysis was performed to find predictors of recurrence.

Results:

Of 483 patients, 127 had IR-NMIBC; 66 and 61 patients received BCG and Gem/Doce, respectively. The median age was 68.5 years (61.2 - 76) and 72 years (62- 76), with a median follow-up time of 53.1 months (25.3 – 71.2) and 20.2 months (8.28 – 33.1) for the BCG and Gem/Doce groups respectively. There was no difference in high-grade RFS between the BCG and Gem/Doce groups (2-year high-grade RFS: 82.8% and 71.2%, log-rank p = 0.11), however, any-grade RFS was inferior in the Gem/Doce group (2-year any-grade RFS (BCG vs. Gem/Doce): 60% vs 41%, log-rank p=0.0036). On Cox regression, induction with Gem/Doce was predictive of any-grade recurrence (HR 1.75, 95% CI [1.1 – 2.96]), while receipt of maintenance therapy was associated with decreased risk of any-grade recurrence (HR 0.4, 95% CI [0.22 – 0.73]). This study is limited by its retrospective design and relatively small sample size.

Conclusion:

In IR-NMIBC composed mainly of TaHG disease, adjuvant treatment with Gem/Doce showed no difference compared to BCG for high-grade recurrence but was inferior for any-grade recurrence. Interestingly, monthly maintenance was found to improve recurrence-free survival, and longer maintenance protocols for Gem/Doce should be considered.

Funding: N/A