10-15 are added to Shipman death list
MPs are calling for revalidation to be used to weed out GPs who are unable to spot the early signs of cancer.
A new report from the Committee of Public Accounts blamed GPs for failing to diagnose cancer effectively.
It accused GPs of 'complacency' and 'arrogance' for not taking their failings seriously.
GPs reacted in fury to the accusations and demanded MPs back them up with facts. They insisted there was no evidence they were delaying referrals.
But committee member Gerry Steinberg, Labour MP for City of Durham, said cancer diagnosis should 'absolutely be brought into revalidation'. He said GPs were 'a law unto themselves' and 'needed to be made more accountable'.
He added: 'What I've found is a number of doctors in specific cases weren't saying it was a priority and the consultant would see them in the normal time frame. That is unsatisfactory.'
The report identified significant disparities in diagnosis of cancer in different areas of the country and found English patients were diagnosed later than their European counterparts. It concluded there were a 'large number of cancer sufferers not initially referred urgently'.
The report said action was needed to help GPs improve their ability to identify symptomatic patients, including better guidance, closer scrutiny and more GPs specialising in cancer.
But Dr Nick Brown, a GP in Chippenham and Cancer lead for Kennet and North Wilts PCT, said the criticism was 'a load of nonsense'.
Responding to Mr Steinberg's comments, he said: 'I've never seen any evidence and until he provides it I think he should keep his mouth shut.'
Dr David Lyon, a GP in Runcorn, Cheshire, and professional executive committee chair at Halton PCT, said he disputed the claim that GPs were responsible for delayed diagnosis. He said when his PCT had audited referrals by GPs, it 'unearthed no evidence GPs were delaying referrals'.
He added: 'MPs need to quantify statements. We need real numbers that have been analysed, not general opinion.'
By Emma Wilkinson