Spatio-temporal analysis of female breast cancer incidence in Shenzhen,2007-2012

Introduction:Breast cancer is a leading tumor with a high mortality in women.This study examined the spatio-temporal distribution of the incidence of female breast cancer in Shenzhen between 2007 and 2012.Methods:The data on breast cancer incidence were obtained from the Shenzhen Cancer Registry System.To describe the temporal trend,the average annual percentage change(AAPC) was analyzed using a pinpoint regression model.Spatial autocorrelation and a retrospective spatio-temporal scan approach were used to detect the spatio-temporal cluster distribution of breast cancer cases.Results:Breast cancer ranked first among different types of cancer in women in Shenzhen between 2007 and 2012 with a crude incidence of 20.0/100,000 population.The age-standardized rate according to the world standard population was 21.1/100,000 in 2012,with an AAPC of 11.3%.The spatial autocorrelation analysis showed a spatial correlation characterized by the presence of a hotspot in south-central Shenzhen,which included the eastern part of Luohu District(Donghu and Liantang Streets) and Yantian District(Shatoujiao,Haishan,and Yantian Streets).Five spatio-temporal cluster areas were detected between 2010 and 2012,one of which was a Class 1 cluster located in southwestern Shenzhen in 2010,which included Yuehai,Nantou,Shahe,Shekou,and Nanshan Streets in Nanshan District with an incidence of 54.1/100,000 and a relative risk of 2.41;the other four were Class 2 clusters located in Yantian,Luohu,Futian,and Longhua Districts with a relative risk ranging from 1.70 to 3.25.Conclusions:This study revealed the spatio-temporal cluster pattern for the incidence of female breast cancer in Shenzhen,which will be useful for a better allocation of health resources in Shenzhen.