There will be more than 12 million new cancer cases and 7.6 million cancer deaths worldwide in 2007, the majority in developing countries, a new report says.

The amounts to 20,000 cancer deaths a day this year, according to Global Cancer Facts and Figures, a publication of the American Cancer Society released Monday. The statistics are based on incidence and mortality data from the International Agency for Research on Cancer's Globocan 2002 database.

The majority of those cases and deaths will occur in developing countries, with 6.7 million cases and 4.7 million deaths versus 5.4 million cases and 2.9 million deaths in developed countries, according to the report.

The report identifies major differences in the most common types of cancers between developed and developing nations:

  • The three most common cancers in men in developed countries are prostate, lung and colorectal cancers.
  • In men in developing countries, the top three cancers are lung, stomach and liver.
  • In women in developed countries, the top three cancers are breast, colorectal and lung cancer.
  • In women in developing countries, the three most common cancers are breast, cervix and stomach.

The report highlights that in developing countries, stomach and liver cancers in men and cervix and stomach cancers in women are related to infection. It also finds that 15 per cent of all cancers worldwide are infection-related, with these types of cancers accounting for 26 per cent of all cancers in developing countries versus eight per cent in developed countries.

"The burden of cancer is increasing in developing countries as deaths from infectious diseases and childhood mortality decline and more people live to older ages when cancer most frequently occurs," said Ahmedin Jemal, an American Cancer Society epidemiologist and co-author of the report, in a release.

"This cancer burden is also increasing as people in the developing countries adopt Western lifestyles such as cigarette smoking, higher consumption of saturated fat and calorie-dense foods, and reduced physical activity."

Approximately 84 per cent of the estimated 1.3 billion smokers in the world are from developing countries, according to the World Health Organization. China alone has 350 million smokers.