WASHINGTON, (Reuters):

Rising tobacco use and poverty will fuel cancer across the developing world, more than doubling the number of new cases to 27 million by 2050, experts predicted last week.

Cancer is already the number two cause of death globally, after heart disease and ahead of AIDS, malaria, tuberculosis and other causes. And as people live longer and adopt bad habits such as smoking, cancer cases will rise, said Dr. Nancy Davidson of Johns Hopkins University in Baltimore.

"It accounts for 10 per cent of deaths," said Davidson, who is president of the American Society of Clinical Oncology.

She cited this week's report by the International Agency for Research on Cancer that 7.6 million people will die of cancer this year, 5 million of them in developing countries.

Contradicting statistics

The statistics contradict a perception that cancer is a disease of rich nations. Cancer deaths have fallen in the United States, dropping by more than 2 per cent between 2002 and 2004.

"There will be 12 million new cancer cases diagnosed worldwide in 2007. By 2050, this number will more than double to 27 million, even if the rates don't change," Dr. Lynn Ries of the U.S. National Cancer Institute said in a telephone briefing.

Of these, 5.4 million cases will be in economically developed countries and 6.7 million in developing countries, Ries said.

Cancer is caused by a mix of factors, including genes, diet, lack of exercise and, rarely, chemical exposure. But the No. 1 cause is smoking.

And more people are using tobacco, said the National Cancer Institute's Deirdre Lawrence.

"According to World Health Organization current estimates, the annual number of tobacco-related deaths worldwide is projected to rise from 4.9 million in 2000 to more than 10 million by 2020, unless effective interventions take hold," Lawrence told the briefing.

She said 70 per cent of the deaths would be in the developing world.

In 1970, 3.26 trillion cigarettes were smoked globally. In 2000, it was 5.7 trillion.

The problem is notably clear in China, said Dr. Tony Mok of the Chinese University of Hong Kong.

"China produced about 39 per cent of the world's tobacco production," Mok told the briefing. About six per cent of this was exported, meaning the rest was consumed in China.

High consumption

"In other words, we consume about 33 per cent of world tobacco production," Mok said. "We smoke a hell of a lot of tobacco."

Mok said 320 million people were smokers in China in 2004, a four per cent increase from 2003.

"Cancer prevention has not been a top priority in our country," he said.

The same goes for India, said Dr. Ketayun Dinshaw, director of the Tata Memorial Centre in Mumbai. He said there are no organised screening programmes in India.

Nigeria tries but poverty intervenes, said Dr. Clement Adebamowo of the University of Ibadan.

"There is limited availability of even basic diagnostic oncology facilities," Adebamowo said. "Chemotherapy drugs are available but are very expensive and not affordable to the majority of cancer patients."