Cancer situation in China: what does the China cancer map indicate from the first national death survey to the latest cancer registration?

Abstract

Background: Over the past four decades, the Chinese government has conducted three surveys on the distribution of causes of death and built cancer registration. In order to shine a new light on better cancer prevention strategies in China, we evaluated the profile of cancer mortality over the forty years and analyzed the policies that have been implemented.

Methods: We described spatial and temporal changes in both cancer mortality and the ranking of major cancer types in China based on the data collected from three national surveys during 1973-1975, 1990-1992, 2004-2005, and the latest cancer registration data published by National Central Cancer Registry of China. The mortality data were compared after conversion to age-standardized mortality rates based on the world standard population (Segi's population). The geographical distribution characteristics were explored by marking hot spots of different cancers on the map of China.

Results: From 1973 to 2016, China witnessed an evident decrease in mortality rate of stomach, esophageal, and cervical cancer, while a gradual increase was recorded in lung, colorectal, and female breast cancer. A slight decrease of mortality rate has been observed in liver cancer since 2004. Lung and liver cancer, however, have become the top two leading causes of cancer death for the last twenty years. From the three national surveys, similar profiles of leading causes of cancer death were observed among both urban and rural areas. Lower mortality rates from esophageal and stomach cancer, however, have been demonstrated in urban than in rural areas. Rural areas had similar mortality rates of the five leading causes of cancer death with the small urban areas in 1973-1975. Additionally, rural areas in 2016 also had approximate mortality rates of the five leading causes with urban areas in 2004-2005. Moreover, stomach, esophageal, and liver cancer showed specific geographical distributions. Although mortality rates have decreased at most of the hotspots of these cancers, they were still higher than the national average levels during the same time periods.

Conclusions: Building up a strong primary public health system especially among rural areas may be one critical step to reduce cancer burden in China.

Keywords: China; cancer control strategy; cancer mortality; cancer registry; national cause of death survey; risk factor.

FIGURE 1

Age‐standardized mortality rates (according to world standard population [Segi's population]) of five leading cancer types by geographic areas in China during four time periods. Large urban, population size > 750 000; medium urban, 750 000 ≥ population size >250 000; small urban, population size ≤ 250 000

FIGURE 2

Age‐standardized mortality rate by the world standard population (Segi's population) of stomach (A), esophagus (B), and liver cancers (C) in ever high‐risk areas (counties with high mortality rates in 1973‐1975) in China during three time periods