Clinical outcomes and patterns of population-based management of urachal carcinoma of the bladder: An analysis of the National Cancer Database.

BACKGROUND: Given the low incidence of urachal carcinoma of the bladder (UCB), there is limited published data from contemporary population-based cohorts. This study aimed to describe demographic, clinicopathological features, and survival outcomes of patients diagnosed with UCB. METHODS: The National Cancer Database (2004-2016) was queried for UCB patients. Descriptive analyses characterized demographics and clinicopathologic features. We assessed 5-year overall survival (OS) rates of the entire cohort and subgroups of localized/locally advanced and metastatic disease. We utilized Cox proportional hazards models to assess the association between covariates of interest and all-cause mortality and to examine the impact of surgical technique and chemotherapy. RESULTS: We identified 841 patients with UCB. The most common histologic subtype was non-mucinous adenocarcinoma (39.6%). Approximately 50% had ≥cT2 disease, and 14.3% were metastatic at diagnosis. Altogether, partial cystectomy (60%) was most performed, and lymph node dissection was performed in 377 patients (44.8%), with specific temporal increase in utilization over the study period (p < 0.001). Overall, median OS was 59 months, and 5-year OS was 49%. In patients with localized/locally advanced disease, we found no association between partial and radical cystectomy (Hazards ratio [HR] 1.75; 95% CI 0.72-4.3) as well as receipt of perioperative chemotherapy (HR 1.97, 95% CI 0.79-4.90) and outcomes. Lastly, receipt of systemic therapy was not associated with survival benefit (HR 0.785, 95% CI 0.37-1.65) in metastatic disease cohort. CONCLUSION: This large population-based cohort provides insight into the surgical management and systemic therapy, without clear evidence on the association of chemotherapy and survival in the perioperative and metastatic setting.