Tumor Location May Predict Adverse Pathology and Survival Following Definitive Treatment for Bladder Cancer: A National Cohort Study.

Background: While urothelial carcinoma of the bladder is often considered a multifocal disease, the location of the dominant tumor may be prognostic.

Objective: To determine the association between intravesical tumor location and both adverse pathological outcomes as well as overall survival. Design, settings, and participants: Patients in the National Cancer Database (2010-2015) with nonmetastatic urothelial carcinoma of the bladder who underwent primary treatment with radical cystectomy (RC; n=3464) or chemoradiotherapy (CRT; n=699). Outcome measurements and statistical analysis: Multivariable logistic regressions assessed the prognostic ability of tumor location to predict adverse pathology at RC (nodal metastases [pN+] or advanced stage [pT3-4]). Cox regressions were used to determine the effect of tumor location on overall survival in patients treated with RC or CRT. Results and limitations: Following RC, 822 (24%) patients were pN+ and 1551 (55%) were pT3-4. Trigonal tumors were most likely to have adverse pathology (31% pN+ and 59% pT3-4), while anterior wall tumors were the least (19% pN+ and 50% pT3-4). Relative to the anterior wall, trigone (odds ratio [OR] 1.65, 95% confidence interval [CI] 1.12-2.43, p=0.012) and bladder neck (OR 1.79, 95% CI 1.11-2.90, p=0.018) tumors were associated with increased odds of pN+ and dome (OR 1.56, 95% CI 1.08-2.24, p=0.017) with pT3-4. In those patients treated with primary CRT, trigone involvement was associated with worse survival (HR 1.58, 95% CI 1.17-2.13, p=0.003). Limitations included unmeasured variables and a relatively few number of patients with certain tumor locations.

Conclusions: Trigone and bladder neck tumors are associated with increased odds of nodal involvement, and dome with a higher tumor stage at RC. Patients with trigone involvement may have worse overall survival following CRT. Patient summary: Location of the tumor within the bladder may be associated with worse cancer staging at the time of the surgery and worse survival following chemoradiotherapy.