A new analysis led by researchers at the American Cancer Society in collaboration with the International Agency for Research on Cancer (IARC) finds lung cancer has surpassed breast cancer as the leading cause of cancer death in females in developed countries. The authors of the report say the change reflects the tobacco epidemic in women, which occurred later than in men. Lung cancer has been the leading cause of cancer death in males in developed countries for several decades. It is also the leading cause of cancer death for males in developing countries, where breast cancer remains the top cause of cancer death in females.
The finding is reported in Global Cancer Statistics, appearing in CA: A Cancer Journal for Clinicians, and a consumer-friendly companion publication, Global Cancer Facts & Figures 3rd Edition, both released on World Cancer Day. The reports rely on the worldwide estimates of cancer incidence and mortality produced by the IARC for 2012 in their GLOBOCAN series.
Cancer now constitutes an enormous burden on society in more and less developed countries alike, and its occurrence is increasing because of the growth and aging of the population, as well as an increasing prevalence of risk factors associated with economic growth and urbanization, such as smoking, being overweight, physical inactivity, and changing reproductive patterns.
An estimated 14.1 million new cancer cases and 8.2 million cancer deaths occurred in 2012 worldwide. In less developed countries, lung and breast cancer are the most frequently diagnosed cancers and the leading causes of cancer death in men and women, respectively. In more developed countries, prostate and breast cancer are the most frequently diagnosed cancers among men and women, respectively, and lung cancer is the leading cause of cancer death in both men and women. Colorectal cancer has become a frequent cause of cancer death not only in developed countries, but also in developing countries.
The researchers point out that breast, lung, and colorectal cancers are increasing in many countries in economic transition with an already disproportionately high burden of cancers related to infection, including cancers of the liver, stomach, and cervix.
"A substantial proportion of the worldwide burden of cancer can be prevented through the application of existing cancer control knowledge, including tobacco control, vaccination (for liver and cervical cancers), early detection, and the promotion of physical activity and healthy dietary patterns," the researchers write. They add that suffering can be further alleviated by applying appropriate treatments and palliative care. In addition, more research is needed to identify the causes of several major cancers, including prostate and blood cancers.
The authors report that a number of cancers that were once rare in developing countries are becoming increasingly common as those countries adopt a more Western lifestyle. "A coordinated and intensified response from all sectors of society, including governments, civil society, the private sector, and individuals, is required to seize control of the growing burden of cancer," they conclude.