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An increase in the incidence of cancer in developing nations means that the international implications of the disease now require greater attention. This increase can be attributed to increased life expectancy in highly populated countries like China and India, a rise in the number of smokers in developing nations and an increase in lung cancer-inducing pollution.

In heavily populated, developing countries, an increase of life expectancy of up to 60 percent from the last century means that, in some of these countries, the number of people over 65 years of age has doubled. Since the risk of developing cancer increases with age, there has been a rise in cancer incidence rates. According to Richard Love, M.D., scientific director of the International Breast Cancer Research Foundation, "The age structure in many developing countries is changing, which means more people are surviving to adulthood and as a consequence, there is a greater burden of adults with major malignancies in developing countries, since the most common malignancies are cancers of aging."

Smoking is one of the most serious issues that can lead to an increase in cancer rates. According to a 2007 report by WHO, there are currently over 350 million smokers in China alone. Similarly, in India, 50 percent of men in the northern states are smokers and are known to use water pipes (popularly known as hookahs or shisha) on a regular basis. Paralleling the increase in smokers, the estimated new cases of oral cancer in 2007 have risen to 129,356 in men and 84,111 in women in developing countries, a notable difference from past years. Since the known risk factors for oral cancers are cigarettes, bidi (small filterless flavored cigarettes), smoking and chewing tobacco, the link between the increased use of tobacco and oral cancers has become more urgent to address. Along with adults being affected by the use of tobacco, the demographic nature of the disease in Southeast Asia is becoming younger. According to a global youth tobacco survey conducted by the CDC, the most frequent users of tobacco products were Southeast Asian students, ranging from ages 13 to 15.

In addition to an increase in oral cancer cases, lung cancer rates are also on the rise globally. Being the leading cause of death by cancer in men and the second leading cause of cancer death in women worldwide, it is estimated that 975,000 men and 376,000 women will die from lung cancer in 2007 alone. In India, lung cancer is the most common form of cancer for men. This is, in part, due to their smoking habits and, in part, due to pollution and exhaust fumes. Smoking cessation and proper tobacco control programs could help alleviate the burden due to lung cancer. Surprisingly, despite their lower prevalence of smoking, lung cancer rates in Chinese women are higher than the rates among women in many European countries. This is thought to reflect indoor air pollution from coal fueled stoves and cooking fumes.

Certain cancers that can be controlled by early interventions are still a major concern in developing countries. Incidence rates for cervical cancer, for example, are exceptionally high in women in India, China and Southeast Asia. Approximately 80 percent of the women who die of this disease globally reside in developing countries and 27 percent of total cases of cervical cancer are found in India. Since the human papilloma virus (HPV) is a known risk factor for cervical cancer and a vaccine is now available to prevent women from contracting the strains of the virus linked to cervical cancer, a lot of these cases could be prevented. Unfortunately, getting this vaccine can be costly and over half of the population in these developing nations cannot afford it. "In India, the higher income population is being treated, but the majority is continuing to be left behind by medical science," said Love.

According to experts, if effective screening and awareness programs were put in place, many deaths from this disease could be prevented. Free women's clinics and health education programs could also assist in helping decrease the mortality rate for cervical cancer and reduce the cost spent on treatment.

Another preventable cancer linked to a virus that is widespread in the developing world is liver cancer. Both hepatitis B (HBV) and hepatitis C (HCV) viruses are associated with liver cancer and can be contracted by direct contact with infectious blood or using contaminated needles. An estimated 711,000 new cases will occur worldwide in 2007, with China accounting for 55 percent of the total. Fifty-nine percent of liver cancers are attributable to HBV and 33 percent to HCV in developing countries. With proper infant immunization and sterilization of needles, these numbers could be reduced, helping relieve some of the burden for those who are suffering from the disease.

Breast cancer, usually dubbed a Western cancer, also affects women in developing countries at an increasing rate. Even though early detection and screening can help reduce those rates, the imaging technology usually required for a mammogram is expensive and only around two to three percent of the population can afford such exams.

With cancer now becoming more of a public health concern internationally, measures are being taken by most of the leading health organizations to alleviate the cancer burden. NCI is committed in playing a role in cancer control globally, most notably in WHO's global cancer prevention and control resolution. In 2005's World Health Assembly, WHO passed a first-of-its-kind resolution, calling for improved cancer prevention measures and improved early detection and treatment in all WHO Member State countries. NCI scientists have joined some of the world's leading cancer control researchers in providing WHO with scientific expertise to develop and implement this global strategy. With everyone doing their part, the increase in cancer trends in the less-developed nations could be controlled and the economic burden of fighting this disease could be lessened.

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