"Cancer should not be a death sentence anywhere in the world, as there are proven ways to prevent and cure many cancers," Dr. Oleg Chestnov, in charge of WHO's non-communicable diseases and mental health unit, said in a statement.

Yet the UN's health body said it had recently conducted a survey of 185 countries revealing that less than half of them, and only 17 percent of countries in Africa, had sufficiently funded cancer control plans.

This is a major concern in a world where each year almost 13 million new cancer cases are diagnosed and some 7.6 million people die of cancer -- a number the WHO warned in 2010 could double to more than 13 million by 2030.

The shortage of functioning cancer control plans is especially alarming in developing countries, since they already account for more than two-thirds of the new cancer cases and deaths each year.

And things are only expected to get worse as populations age and increasingly feel the impact of exposure to major risk factors like tobacco, certain chemicals and infections, according to Dr. Andreas Ullrich, of WHO's Department of Chronic Diseases.

"We expect, especially in metropolitan areas of the developing world, to see a major increase in cancer," he told reporters in Geneva Friday.

The agency pointed out that up to a third of all cancer deaths are linked to "modifiable risks" like tobacco, obesity and harmful use of alcohol.

Vaccines exist for some infections linked to cancer, including hepatitis B, which can cause liver cancer, and papillomavirus, which can cause cervical cancer.

And if detected early on, many types of cancer can be cured, the agency pointed out.

"In order to reduce exposure to risk factors leading to cancer and ensure that every person living with cancer gets access to appropriate care and treatment, comprehensive cancer control programmes need to be set up in every country," Chestnov said.