The new report estimates that 5.4 million of those cancers and 2.9 million deaths will occur in economically developed countries, while 6.7 million cases and 4.7 million deaths will occur in developing countries.

In developed countries, the three most commonly diagnosed cancers in men are prostate, lung, and colorectal cancer. Among women, they are breast, colorectal, and lung cancer. In contrast, the three most commonly diagnosed cancers in developing countries are cancers of the lung, stomach, and liver in men, and cancers of the breast, cervix uteri, and stomach in women.

In developing countries, two of the three leading cancers in men (stomach and liver) and in women (cervix and stomach) are related to infection. Approximately 15 percent of all cancers worldwide are infection-related, with the percentage of cancers related to infection about three times higher in developing than in developed countries (26 percent versus 8 percent). “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, PhD, American Cancer Society epidemiologist and co-author of the report. “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.”

The publication includes a special section on tobacco’s increasing toll. An estimated five million people worldwide died from tobacco use in the year 2000. Of these, about 30 percent (1.42 million) resulted from cancer, with 850,000 deaths from lung cancer alone. Overall, tobacco was responsible for about 100 million deaths around the world during the 20th century.; Source: American Cancer Society