While incidence and mortality rates from several common types of cancer have gone down in many high-income countries, many low-and middle-income countries have seen cancer rates rise, partially due to increases in risk factors that are typical of Western countries, says a study.
Improved screening and detection efforts, combined with decreases in risk factors like smoking, have reduced the incidence and mortality rates from cancer in high-income countries, the findings showed.
Worldwide, an estimated 14.1 million new cancer cases and 8.2 million cancer deaths occurred in 2012, the study said.
"This study gives us important clues about the epidemiology of cancer and gives us some ideas about what we could further investigate to improve global public health," said one of the researchers, Lindsey Torre from the American Cancer Society.
The researchers analysed incidence and mortality data for the years 2003-2007 from the International Agency for Research on Cancer (IARC) database, which includes incidence data through 2007 from cancer incidence in five continents, and mortality data through 2012 from the WHO Cancer Mortality database.
Study data reflected 50 countries selected to represent various regions of the world.
The authors noted developments across eight major kinds of cancer, which account for 60 percent of total global cases and deaths.
The report detailed trends in breast, prostate, colorectal, lung, esophageal, stomach, liver and cervical cancers.
The incidence and mortality of many of these cancers have decreased in high-income countries, but risen in low-and middle-income countries due to factors that may include lifestyle changes and lack of appropriate screening or prevention measures.
Cancer is a leading cause of death worldwide in countries of all income levels, and the number of cancer cases and deaths is expected to grow rapidly as populations grow, age, and adopt lifestyle behaviours that increase cancer risk.
The study was published in the journal Cancer Epidemiology, Biomarkers and Prevention.