Background: In France, prostate cancer is at the top of the list of the most common cancers in men. The morbidity and mortality of this cancer were found to be related to the geographic level of socioeconomic deprivation with a higher rate of mortality and more frequent aggressive cases among men with low socioeconomic level, this was associated with health disparities in the management of this cancer. Our study region is considered as an economically deprived area with a poverty rate significantly higher than the national average. Aim: The aim of our study was to assess the impact of the socioeconomic level on the incidence, mortality, aggressiveness and management of prostate cancer, using data from a population-based cancer registry. Methods: For this research, prostate cancer data, between 2006 and 2010, were obtained from the Somme area cancer registry. Social economic status was assessed using the European Deprivation Index (EDI). This index has been used to classify each geographical unit (IRIS) according to social deprivation. IRIS is the smallest submunicipal geographical entity for which census data are available. Each prostate cancer case was allocated to the corresponding IRIS by geolocalizing the addresses using geographic information system (GIS). For spatial analysis, hierarchical generalized linear modeling was fitted. To assess for spatial autocorrelation, Moran's I test was conducted and then spatial autocorrelation was modeled by a set of random effects that are assigned a conditional autoregressive (CAR) prior distribution. Results: A total of 2405 incident cases of prostate cancer were registered in the Somme area. The age-standardized rate was 98.2 cases per 100,000 person-years (PY). The standardized mortality rate was 28.1 deaths per 105 PY. The coefficient associated with the EDI obtained from the spatial analysis of prostate cancer incidence was negative (-0.348; 95% CI: −0.0831) which indicates that prostate cancer incidence was more important in the less deprived areas. The relative risk of prostate cancer mortality associated with the quintile 5 of the EDI relatively to quintile 1 was 3.09; 95% CI: [1.70-5.59]. For the aggressiveness, the coefficient associated with the EDI was 0.0493 with a 95% CI: [0.0162-0.0810], and the Q5/Q1 RR was equal to 1.36 95% CI: [1.09-1.73]. EDI estimated coefficient for proportion of cases who received curative treatment versus patients who received palliative treatment was −0.1089, 95 CI%: [−0.1505 to −0.0693]. EDI coefficient for waiting time was not significant. Conclusion: Our study showed a significant association between socioeconomic deprivation and prostate cancer with worse outcomes among men with the lowest socioeconomic status. Geographical differences in screening rate could explain this pattern. More in-depth research with a source data review is required to know precisely the determinism of this association and therefore adjust the eventual disparities.
Estimation of Esophageal Cancer Incidence in Tehran by Log-linear Method using Population-based Cancer Registry Data
