At Armstrong's request, the four doctors developed a national 'call to action' against cancer that emphasises prevention efforts such as not smoking, eating more fruit and vegetables, getting less fat in the diet, getting more exercise, using sunscreen and avoiding indoor tanning beds.

It also encourages people to get recommended cancer screening tests such as mammograms for breast cancer to detect tumours early when they respond best to treatment. And it emphasised the need to provide better care for the roughly 12 million cancer survivors in the United States.

'The war on cancer begins with prevention,' Dr Carmona said. 'Today, we have a better understanding about how cancer works and have developed tools for better screening, diagnosis and treatment. Half of all new cancer cases could be prevented or detected earlier when they are most treatable.' Their plan is on the Internet at http://www.NCTAcancer.org.

The cancer death rate for men has fallen by 18.4 per cent since peaking in 1990 and for women has fallen by 10.5 per cent since peaking in 1991, the American Cancer Society said.

The declines have been driven by improved treatment and screening methods as well as progress toward prevention such as declining smoking rates, the organisation said.

The post of surgeon general, the nation's top doctor, has been unfilled since Dr Carmona finished his term in 2006. -- REUTERS