[Analysis and prediction of breast cancer incidence trend in China]

Abstract

Objective: Based on the registered female breast cancer data from 1998 to 2007, to analyze the incidence of female breast cancer during the period and then to predict its trend from 2008 to 2015.

Methods: The incidence data of breast cancer from 1998 to 2007 were sorted from National Cancer Registry Database, including 74 936 cases from urban areas and 8230 cases from rural areas, separately covering 164 830 893 and 55 395 229 person years. The crude incidence rates in urban and rural areas were calculated, and the age-standardized rate (ASR) was adjusted by World Segi's population composition. JoinPoint software was applied to analyze the 10 years' incidence trend and calculated the annual percentage of changing (APC), while Age-Period-Cohort Bayesian Model was used to fit the data and predict the incidence of breast cancer between 2008 and 2015.

Results: From 1998 to 2007, the incidence of breast cancer in the urban cancer registration areas was 45.46/100 000 (74 936/164 830 893), whose ASR was 31.28/100 000. While in rural registration areas, the incidence and ASR was 14.86/100 000 (8230/55 395 229) and 12.13/100 000. The breast cancer incidence in urban and rural areas separately rose from 36.17/100 000 (3920/10 838 355) and 10.39/100 000 (436/4 197 806) in 1998 to 51.24/100 000 (11 302/22 057 787) and 19.61/100 000 (1475/7 522 690) in 2007. During the 10 years, the breast cancer incidence increased both in urban and rural areas, but the increase rate in rural incidence (6.3%) was more significant than it in urban areas (3.9%). Age-Period-Cohort Bayesian Model predicted that the breast cancer incidence would increase to 53.87/100 000 (185 585 new cases) in urban areas and 40.14/100 000 (132 432 new cases) in rural areas, respectively.

Conclusion: The breast cancer incidence has been increasing annually both in urban and rural areas in China; and an annually increase number of new cases have been predicted.