Abstract 4131: Individual and contextual factors associated with overall prostate cancer survival in Florida
Authors: Xiao Hong , Tan Fei , Adunlin Georges , Ali Askal , Goovaerts Pierre , Huang Youjie , Gwede Clement K. 
Published: May 2015

Background: Few studies have looked at the independent contribution that individual-level and contextual factors make to prostate cancer survival. The objective of this study was to identify individual and contextual factors contributing to overall prostate cancer survival in Florida.

Methods: A random sample of 6453 cases diagnosed with prostate cancer between 10/1/2001 and 12/31/2007 in the Florida Cancer Data System provided data on: demographics, type of health insurance at diagnosis, tumor stage, treatment and all-cause death. Census-tract level socioeconomic status & farm house presence were extracted from Census 2000 and linked to patient data. Comorbidity was computed following Elixhauser Index. Estimated survival probability curve was generated using the Kaplan-Meier estimator. Wei, Lin and Weissfeld (WLW) survival model was adopted for the multivariate analysis. Times from prostate cancer diagnosis to overall mortality were evaluated for patients who died during study period. The observation times were censored at June 30, 2012 for patients who were still alive at end of study. Hazard ratios, confidence intervals, and p-values were calculated.

Results: The average age at diagnosis was 66.55 years with 12.16% men being diagnosed with advanced stage. The range of observation period was 5 to 3925 days, where 1100 patients (17.05%) died during this period. Among patients who died, 50% died within approximately 3 years after diagnosis. Older diagnosis age was associated with shorter time-to-death. Overall death rate for African American patients was 14.3% higher than that of Caucasian patients, although this relationship was not significant (p = 0.2305). Patients with no insurance had a 66.7% higher mortality rate than that of patients holding private insurance (p = 0.0351). Mortality rate for current smokers was 62.4% higher than that of non-current smokers (p &lt; 0.0001). Higher hazard of overall mortality was also associated with being diagnosed with advanced stage compared to localized stage (HR = 1.89, p &lt; 0.0001) and having undifferentiated or unknown tumor compared to well-moderately differentiated tumor (HR = 1.36, p = 0.0172). Having poorly differentiated tumor was related to higher death rate immediately after diagnosis, but this disadvantageous effect gradually vanished over time. Fourteen comorbidity conditions were significantly associated with shorter time-to-death.

Conclusions: Older age and late stage at diagnosis, being black, having no insurance, being a smoker, having poorly-differentiated, undifferentiated or unknown tumor, and comorbidity status were prognostic indicators for shorter survival. Effective control of comorbidity in prostate cancer patients should help improve life expectancy and lead to prolonged survival. Further research is needed to understand mechanisms in which individual and contextual factors impact prostate cancer survival.

Citation Format: Hong Xiao, Fei Tan, Georges Adunlin, Askal Ali, Pierre Goovaerts, Youjie Huang, Clement K. Gwede. Individual and contextual factors associated with overall prostate cancer survival in Florida. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4131. doi:10.1158/1538-7445.AM2014-4131