Dr Peter Boyle, director of the International Agency for Research on Cancer, said the reasons for the increase included population growth, increased life expectancies and the transfer from the developed world to the developing world of cancer risk factors such as smoking. These added to the existing risks in poor countries such as communicable diseases and lack of health care.
In 2000 the agency estimated 11 million new cases of diagnosed cancer worldwide, seven million deaths from cancer and 25 million people living with cancer.
“We estimate that between the year 2000 and 2030, there’ll be a more than doubling of the numbers of cases of cancer diagnosed each year,” Dr Boyle said. “And the great majority of this increase is going to be in the low- and medium-resource countries.”
The agency expects that by the year 2030, there will be 27 million cases of cancer, 17 million deaths from cancer and 75 million people living with cancer.
“We’ve been concentrating on cancer in high-resource countries and until essentially AIDS came along, we haven’t looked too closely at what’s going on in low-resource countries,” Dr Boyle said.
But he says new research shows that as time has progressed, there has been an increasing shift of cancer to poor countries.
“What’s going to happen between now and 2030 is that the population is going to increase from about 6.5 billion to eight billion in 2030,” he said. “Even if the risks remain constant at each five-year age group, because we’ve got more people around, we’re going to have more cases of cancer.”
A second factor leading to a rise in cases is the increase in life expectancy in the majority of countries, with the exception of some Aids-ravaged countries, he says.
The agency has just finished an estimate of cancer cases and deaths in all UN World Health Organisation regions which found that breast cancer was the commonest or second commonest form of cancer in every region of the world.
The study also found that the commonest type of cancer for men in Africa was Kaposi’s sarcoma, which is directly linked to the Aids/HIV epidemic there.
The agency found that there were commonly more people in the world who died of cancer than those who died of tuberculosis, Aids and malaria combined.