Differences in breast cancer incidence and stage distribution between urban and rural female population in Podlaskie Voivodship, Poland in years 2001-2002.

Medical University of Bialystok, Department of Public Health, Bialystok, Poland. m.krzyzak@umwb.edu.pl
Ann Agric Environ Med 2010;17(1):159–162
The aim of the study was to evaluate differences in breast cancer incidence and stage of disease between the urban and rural female population in Podlaskie Voivodship in 2001-2002, before the introduction of the Population Screening Programme in 2006. Analysis was based on 696 breast cancer cases diagnosed in years 2001-2002 and registered in the CR in Bialystok (Voivodship Cancer Registry). An average annual number of incidence, as well as crude and standardised incidence rates, were calculated. Age-specific incidence rates for 5-year age groups were also calculated and grouped as follows: < 50, 50-69, > =70 years old. Incidence differences related to place of residence: urban or rural, were presented with the use of u/r (urban/rural) ratio. In order to evaluate the stage of disease, a simplified classification recommended by ENCR (European Network of Cancer Registries) for population registries (localised, regional, metastatic) was applied. The breast cancer incidence rate in the urban population was higher than in rural areas with u/r ratio amounting to 1.4. The highest incidence and largely marked differences between urban and rural areas were among women aged 50-69 years with the u/r ratio amounting to 1.8. Overall, the proportion of stage localised in Podlaskie Voivodship was 33.1 percent and differed between urban and rural areas. The proportion of localised cancer was higher in urban areas, but patients were younger when compared to those living in rural areas. Knowledge of differences in incidence and breast cancer stage in urban and rural women investigated in this research, together with other epidemiological indicators, should be used for monitoring the Population Screening Programmes in these populations.