Objective: The oncological basis behind the observation that females experience worse outcomes following radical cystectomy for urothelial carcinoma of the bladder (UCB) is unclear. This study was aimed at examining the sole effect of gender on postcystectomy UCB outcomes and identifying potential factors that may explain the poor prognosis in females using a balanced case-control approach.
Materials and methods: A review of 2,567 patients with UCB who underwent radical cystectomy identified 414 females ("cases") who were matched 1:1 for demographic, tumor, and treatment characteristics with 414 male counterparts ("controls"). Cases were also compared with an independent male UCB cohort (n = 1,166). Differences between females vs. matched control and independent male patients with UCB were analyzed. Recurrence-free survival, cancer-specific survival, and overall survival were compared by univariable and multivariable Cox regression models.
Results: Median follow-up for cases, controls, and independent control cohort was 12.2, 8.6, and 13.5 years, respectively. Females were matched to male controls for tumor and nodal stages (P = 1.00), lymphovascular invasion and surgical margin status, age, prior intravesical treatment, and neoadjuvant and adjuvant chemotherapy administration (P = 0.61-1.00). Cases were also balanced with controls for grade, p53 status, nodal yield, American Society of Anesthesiologists score, presence of hydronephrosis, and times to diagnosis and cystectomy (P ≥ 0.14). When thus matched, outcomes between females and males were not different (P ≥ 0.34). However, when compared with an independent unmatched male control cohort, females had significantly poorer outcomes (P ≤ 0.006). In this comparison, females presented with higher tumor (P<0.001) and nodal (P = 0.049) stages and a lesser proportion received precystectomy intravesical therapy (P = 0.032).
Conclusions: Females have similar UCB outcomes to males when matched for demographic, clinicopathologic, and management characteristics. However, they present with more advanced tumors, thus explaining the observation of poor outcomes.
Keywords: Bladder cancer; Case-control studies; Female; Prognosis.
Copyright © 2014 Elsevier Inc. All rights reserved.