The government's two-week target for cancer referrals has backfired, forcing many women with breast cancer to wait several months to see a specialist, according to new evidence.

Information collected by the British Association of Surgical Oncology shows that up to a third of breast cancers are detected in women referred as non-urgent cases. But the wait for a non-urgent appointment has soared from about six weeks to between 14 and 18 weeks.

Speaking at a Breakthrough Breast Cancer conference in London last week, BASO executive member Paul Sauven said the number of inappropriate GP referrals had increased by between 20 and 40 per cent since the two-week rule came into effect in April.

With no additional staff or resources, breast clinics are being swamped with women referred 'urgently' who do not have cancer and who have been sent by GPs simply wanting to cover themselves or placate a patient.

'There is no biological reason whatsoever for the two-week rule. It's about allaying patient anxiety not about public health, ' Mr Sauven, a consultant at Broomfield Hospital, Chelmsford, said.

BASO has already raised its concerns with the Department of Health, which refused to involve it or other professional groups in the development of the latest referral guidelines.

Dr Joan Austoker, director of the Cancer Research Campaign education research group and author of the national referral guidelines, also condemned the way the target has been forced through.

Dr Austoker said she had been commissioned to update the guidelines in a rush because the DoH wanted to include the two-week rule. She had not been given time to carry out the extended consultation, testing and education generally needed to ensure guidelines were effective.

She said clinics were now being overwhelmed by 'urgent' referrals, most of which were inappropriate, and expressed concern about the government's commitment to extend the two week rule to other forms of suspected cancer.

'I am very unhappy that we are about to rush into introducing this rule for another 12 cancer sites when there is very clear evidence of problems, ' she said.

Concern about the effect of the target is shared by GPs, who feel obliged to send patients for a specialist consultation if they expect or demand it.

Dr Ivan Cox, Macmillan GP adviser, said the rule had actually diminished the possibility of early recognition of cancer and had 'de-skilled' GPs.