We need to focus on the key priorities and expand capacity across the NHS in every area that we can

John Hutton, health minister

Professor Karol Sikora, a cancer specialist at Hammersmith Hospital in London, warned that delays could mean life or death for some people.

"For a small number, and we can't know which they are, if they don't get treated promptly the disease has the chance to spread around the body and eventually they will die from their cancer," he told the BBC.

Doctors advise that women with breast cancer should be treated within four weeks of surgery.

But the BBC investigation found one patient in Hertfordshire had to wait 17 weeks.

In west London some women can wait up to 16 weeks.

Going private

The Wycombe General Hospital in Buckinghamshire uses its website to warn patients they face a two to three month wait unless they go private.

It says the team uses the Harley Street Clinic in London which, for non-insured patients, could cost between �5,000 and �5,500.

Anne Johnstone, who has a brain tumour, says she is angry at being forced to wait.

She should have had radiotherapy treatment within four weeks, but nine weeks later she is still waiting.

"From one day to another you feel your energy going and energy is necessary to cope," she said.

"You are dealing with human beings, you are dealing with people and you are taking away the quality of life. That is my anger."

'Key priorities'

A long wait for treatment is not restricted to cancer patients, the investigation found.

Thousands of elderly patients are being left without hearing aids - in Southampton patients can wait nearly two years for a hearing test.

Disturbed children across the UK can wait up to nine months or longer to see a psychologist.

And children who need speech therapy can wait up to two years.

Health minister John Hutton said patients across the board do have to wait too long for treatment.

"That is why it is important why we need to focus on the key priorities and expand capacity across the NHS in every area that we can," he said.

Our correspondent says the government insists the focus on waiting times for surgery has not been at the expense of patients needing "less glamorous" treatments.