Introduction:

High-grade prostatic urethral involvement in patients with non-muscle invasive bladder cancer (NMIBC) is classified as high-risk according to the American Urological Association (AUA) guidelines, although the best treatment approach is not well-established. Limited evidence exists for bladder-sparing treatments in these patients. Herein we report on the outcomes of patients with high-grade prostatic urethral involvement treated with bladder sparing options.

Methods:

We performed an IRB approved review of consecutive patients diagnosed with NMIBC between January 2005 and May 2023 to identify patients with urothelial carcinoma involving the prostate.  Since our goal was to report on outcomes of patients who received bladder sparing intravesical therapy as primary treatment, we excluded patients with BCG-unresponsive tumors (n=10) and those undergoing upfront radical cystectomy (n=10). The primary outcome was high-grade disease-free survival (DFS), defined as patients alive without high-grade disease in the prostate or bladder. The Kaplan Meier (KM) method was used to estimate DFS, cystectomy rate, progression free survival (PFS, and overall survival (OS).

Results:

The study included 42 patients with high-grade urothelial carcinoma of the prostate (papillary only: 11, mucosal CIS: 14, CIS involving ducts and acini: 17). Repeat transurethral resection was performed in 31 (74%) cases prior to intravesical therapy. Concurrent NMIBC was present in 35 patients (Ta: 12, T1: 10, CIS only:13, and concomitant CIS:10). Forty patients received BCG and two patients received intravesical chemotherapy. At the 3-month assessment, 29 patients (69%) were disease-free; 90% of these received ongoing maintenance treatment. Despite this, 30 (71%) of patients recurred at a median of 7 months (IQR 3.8 to 12 months) and 17 (40%) patients had a cystectomy at a median of 10 mos. (IQR 8.4-14). Progression to muscle-invasive or metastatic free survival at 1 year was 85% (95% CI 72-92). Kaplan Meier DFS curves stratified by CIS ducts/acini, CIS mucosal and papillary only is shown in Figure 1.

Conclusion:

Patients with high-grade urothelial carcinoma of the prostate treated with intravesical therapy have high rates of recurrence and progression within the first year of treatment. Vigilant follow-up is mandatory if bladder-sparing treatment is pursued, as there is limited time to assess effectiveness of intravesical therapy for these patients.

Funding: n/a