Nature Clinical Practice Oncology (2006) 3, 582-583

Received 22 March 2006 | Accepted 10 July 2006

Cancer in the developing world: can we avoid the disaster?

Franco Cavalli

Correspondence International Union Against Cancer, 62 Route de Frontenex, CH-1207 Geneva, Switzerland

Email iosidirezione@iosi.ch

Based on the most recently estimated rates of current cancer incidence and the projected demographics for the next half century, the 11 million cancer cases diagnosed in 2002 (double the number diagnosed two decades earlier) will reach roughly 17 million in 2020 and 27 million by 2050.1 These estimates assume no change in the risk pattern of cancer incidence. A yearly increase of 1% would add roughly another million cases per year.2 For many types of cancer, however, the expected increase in risk will be much higher than 1% annually, especially in low-income countries.3 Close to two-thirds of the cancer cases predicted for 2050 will occur in low-income countries, though only 20 years ago the proportion of cases was similar in the developed and the developing countries of the world. A much lower cure rate in low-income countries means that the difference in mortality will be even more pronounced. In fact, it has been predicted that by 2020 almost two-thirds of the deaths from cancer will occur in developing countries, and this proportion could reach three-quarters well before 2050.1, 2 This shift in cancer mortality risk has occurred because in developing countries tumors related to Western life styles (e.g. breast cancer) are accumulating in addition to poverty-linked tumors (e.g. cervical cancer). Life expectancy is increasing in many low-income countries, and some of these countries will soon have a demographic structure similar to those of Western countries. This is important, because it has been calculated that by 2050 three in five cancer cases will occur in the elderly, compared with two in five at the beginning of this century.2 A recent study has demonstrated that deaths attributable to potentially modifiable behavioral and environmental risk factors are rapidly becoming more important in low-income countries as compared with more affluent regions.4 The most relevant differences between the two parts of the world are in the fields of early detection and treatment. Early detection remains elusive for the vast majority of the population in resource-poor countries, even in tumors such as cervical cancer, for which the efficacy and economic viability of early detection has been clearly demonstrated. Differences in treatment outcomes are sometimes huge, with pediatric oncology being the most dramatic example. While in the developed world cure rates following childhood cancer are approximately 75%, these percentages drop to 10–15% or even less in many low-income countries. It has been calculated that almost 100,000 children die from cancer every year who could have been cured had they received appropriate treatment.5 We have to assume that overall differences in cancer outcomes will soon increase further. In fact, the health systems in many countries that have limited economic resources are undergoing a profound crisis. Moreover, diagnosis and treatment for most tumors are becoming more sophisticated and chiefly much more expensive. This increase in cost could have a dramatic impact in countries in which the health expenditure per capita is only a few dollars yearly; some health systems, even in the most affluent Western countries, have increasing difficulties in being able to provide the most expensive new drugs.6 The dramatic situation prevailing in the treatment of HIV-infected people, whereby most countries are unable to afford modern therapies, could soon also become a reality in oncology. We should not consider this bleak forecast as an unavoidable natural event. There are many ways in which the situation can be improved, but a worldwide coordination of huge efforts is required. Even in countries where the primary care system is unaffordable or unavailable for the vast majority of people, some important preventive measures can be implemented. It has been calculated, for example, that about a quarter of all tumors are smoking-related.4 Notwithstanding that many countries have signed the WHO Framework Convention on Tobacco Control treaty, the tobacco industry is forestalling legislation, especially in resource-poor countries.7 The oncology community should do whatever is possible to end this deadlock. The campaign for vaccination against hepatitis B virus is gaining momentum and the same should be true very soon for human papillomavirus.8 It has been calculated that these measures could save at least half a million lives each year by reducing the incidence of liver and cervical cancer.3 The possibilities for early diagnosis are rapidly increasing, and some screening procedures are even becoming more affordable. Mass screening should ideally become available free of charge for the vast majority of the population through a functioning primary care system. Both the International Union Against Cancer (UICC) and WHO are refining guidelines that allow the development of cancer control interventions, which should be cost-effective and tailored to the different resource settings. Important improvements in outcome at an affordable cost have been achieved in the pediatric specialty through a close cooperation between institutions in the developing and the developed nations.9 Similar models are the basis for the UICC worldwide campaign ’My child matters’, and such models could also be applied with minor modifications in adult cancer patients.10 Since a proportion of cancers will remain incurable for the foreseeable future, palliative care must be developed worldwide urgently. This will require a much wider use of cheap opioids and a rapid dissemination of much new knowledge that has recently been generated in this field. As has been partially the case for HIV, the price policy of pharmaceutical companies must also be discussed in oncology, and worldwide affordable solutions urgently sought.6 The most important step, however, is to include cancer on the world political agenda. A number of wealthy new players have recently reshaped how affluent countries confront infectious diseases in the developing world; however, cancer kills more people than tuberculosis, malaria and HIV put together. Improving the outcome in oncology will undoubtedly also have profound economic impact. Therefore, the implementation of a cancer control plan, encompassing prevention and treatment in each country, should become a declared goal of health policy makers worldwide. A first step has been accomplished by the World Health Assembly of the WHO in May 2005, when the fight against cancer was for the first time declared a priority for all governments.11 Nevertheless, only a broad alliance including also non-governmental organizations such as the UICC and the major health charities will develop the necessary strength and resources to avoid the cancer disaster that is looming in the developing world.

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