The past century or so has seen unprecedented technological, scientific and sociological evolution worldwide. These have been accompanied by global shifts in people’s lifestyles and rapid environmental changes, both natural and man-made. An adverse consequence of these changes is the increasing burden of cancer on human society.
As the country with the largest population, China has borne this burden heavily. Despite the huge strides China has made in health care since the 1950s, cancer has become the leading killer in the country. In 2015, nearly 2.4 million lives were taken by this disease. Cancer is latent for years before manifesting; so perhaps the burden will only increase in the coming decades.
But if you break down these stats by cancer type and risk factor, what do the most notable trends look like? A group of researchers reviewed data from several national death surveys, cancer registries and online databases to find out.
About their motivations for conducting the assessment, lead researcher Dr. Wanqing Chen, director of the Office of Cancer Screening, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, China: “This assessment provides scientists and policy makers with a tool to find what works, what matters and what is expected.” The paper is Open Access published in Cancer biology and medicine.
The team’s study of 22 Chinese registries revealed an increase in cancer incidence from 2000 to 2011, with the increase largely due to increased incidence of colorectal, prostate, breast, cervical and ovarian cancers. Interestingly, the incidence of liver, esophagus, and stomach cancer has decreased significantly. This may be due to widespread hepatitis B vaccination across the country during this period, in addition to an overall improvement in food storage practices and living conditions.
Cancer mortality data from 1990 to 2015 reflected incidence data with increasing death rates observed in colorectal, pancreatic, and breast cancers and decreasing rates observed in gastric, esophageal, and liver cancers. But while the burden of these upper gastrointestinal cancers has dropped significantly, it still hangs heavily.
Between 1990 and 2017, lung cancer climbed to the top of the list of several cancers responsible for years of healthy life lost through illness, disability, or death (disability-adjusted life years, DALYs). Liver and stomach cancers were second and third in line.
Unfortunately, further research suggests that a fairly large proportion of these cases and deaths may have been preventable. Data from the National Cancer Center, China, attributes 45% of cancer deaths in the country to modifiable risk factors — behavioral, clinical, or environmental. For example, 23.8% of cancer deaths in men and 4.8% in women in 2014 are attributed to smoking. From 1990 to 2017, cancer deaths caused by smoking increased by more than 150%. Given that China currently consumes about 40% of the world’s tobacco, the future looks grim if its habits don’t change.
Aside from smoking, physical inactivity, an unhealthy diet and heavy alcohol use are major behavioral risk factors for cancer; diabetes, obesity and infectious diseases are prominent clinical risk factors; and air pollution, as well as occupational exposure to carcinogens such as soot, asbestos and silica, are major environmental risk factors.
But even in these apparently dark times there is a bright spot. Technological advances coupled with good health and insurance policies and a growing public awareness may have helped improve cancer survival rates between 2003 and 2015.
Still, prevention is better than cure. Like dr. Chen explains: ”Summarizing all this critical information, one can see that implementing cost-effective primary prevention approaches is paramount. Our paper highlights the need for concerted efforts by the government, public health organizations and the people to reduce the cancer burden in the country. We hope our work can inform policies such as Healthy China 2030.”
Perhaps the successful implementation of policies based on such research in China and worldwide can lift the burden of cancer off the shoulders of the world.
Authors: Dianqin Sun (1), He Li (1), Maomao Cao (1), Siyi He (1), Lin Lei (2), Ji Peng (2), Wanqing Chen (1)
Title of original paper: Cancer Burden in China: Trends, Risk Factors and Prevention
Log : Cancer Biology and Medicine
(1) Cancer Screening Department, National Cancer Center/National Cancer Clinical Research Center/Cancer Hospital, Chinese Academy of Medical Sciences and Beijing Union Medical College, China
(2) Department of Cancer Prevention and Control, Shenzhen Center for Chronic Disease Control, China;
About Dr. Wanqing Chen
dr. Wanqing Chen is director of the Office of Cancer Screening, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, China. He is also affiliated with the Chinese Academy of Medical Sciences and Peking Union Medical College, China. Over the course of his career, he has led multiple research programs of national and international importance and conducted several nationally important public health projects, including the Third National Retrospective Mortality Study and a Cancer Early Diagnosis and Treatment Program. An authoritative figure in the field of cancer research, he has published over 300 academic papers as lead author or corresponding author; and as editor in chief or deputy editor, he has compiled 13 monographs.
Cancer Biology and Medicine