Introduction

We evaluated epidemiologic trends and survival for bladder cancer histologic subtypes in California patients by comparing urothelial carcinoma of the bladder (UCB) and non-urothelial subtypes including squamous cell carcinoma (SCC), adenocarcinoma (ADC), and small-cell carcinoma (SmCC).

Materials and methods

The California Cancer Registry (CCR) was queried for incident bladder cancer cases from 1988 to 2012. Epidemiologic trends based on tumor histology were described. The primary outcome was disease-specific survival (DSS). Kaplan-Meier and multivariable Cox regression survival analyses were performed.

Results

A total of 72,452 bladder cancer cases (66,260 UCB, 1390 SCC, 587 ADC, 370 SmCC, and 3845 other) were included. The median age was 72 years (range, 18-109 years). ADC was more common in younger patients. Male:female ratios varied among cancer types (3.1:1 in UCB, 2.9:1 in SmCC, 1.6:1 in ADC, and 0.9:1 in SCC). Most non-urothelial cases (> 60%) presented at advanced stages, whereas most UCB cases (80.6%) were localized. Kaplan-Meier analysis revealed the best 5-year DSS and overall survival (OS) in UCB, whereas the worst outcomes were seen with SCC and SmCC (P < .0001). Multivariable analysis controlling for age, gender, tumor stage, and grade demonstrated that non-urothelial histologic subtypes were associated with significantly worse DSS compared with UCB (SCC hazard ratio [HR], 2.612; SmCC HR, 1.641; and ADC HR, 1.459; P < .0001).

Conclusions

Non-urothelial bladder cancers have worse oncologic outcomes than UCB in California patients. SCC and SmCC are associated with the worst DSS based on univariable and multivariable analyses.

Purpose

To examine the California Cancer Registry (CCR) for bladder cancer survival disparities based on race, socioeconomic status (SES), and insurance in California patients.

Patients and methods

The CCR was queried for bladder cancer cases in California from 1988 to 2012. The primary outcome was disease-specific survival (DSS), defined as the time interval from date of diagnosis to date of death from bladder cancer. Survival analyses were performed to determine the prognostic significance of racial and socioeconomic factors.

Results

A total of 72,452 cases were included (74.5% men, 25.5% women). The median age was 72 years (range, 18-109 years). The racial distribution among the patients was 81% white, 3.8% black, 8.8% Hispanic, 5.2% Asian, and 1.2% from other races. In black patients, tumors presented more frequently with advanced stage and high grade. Medicaid patients tended to be younger and had more advanced-stage, higher-grade tumors compared to patients with Medicare or managed care (P < .0001). Kaplan-Meier analysis demonstrated significantly poorer 5-year DSS in black, low SES, and Medicaid patients (P < .0001). When controlling for stage, grade, age, and gender, multivariate analysis revealed that black race (DSS hazard ratio = 1.295; 95% confidence interval, 1.212-1.384), low SES (DSS hazard ratio = 1.325; 95% confidence interval, 1.259-1.395), and Medicaid insurance (DSS hazard ratio = 1.349; 95% confidence interval, 1.246-1.460) were independent prognostic factors (P < .0001).

Conclusion

An analysis of the CCR demonstrated that black race, low SES, and Medicaid insurance portend poorer DSS. These findings reflect a multifaceted socioeconomic and public health conundrum, and efforts to reduce inequalities should be pursued.