The unexpected finding, which appears in The Lancet, triggered a dispute before it was published. A second paper in the journal said delays of over three months had no effect on survival: its author said he had been excluded from a press conference called to announce the results of the two studies.
The suggestion that a few months' delay can reduce survival is controversial because it will increase pressure on hospital breast clinics and put GPs at risk of litigation if they "watch and wait" rather than referring patients with symptoms. It is also counter to medical orthodoxy.
About 30,000 women a year in Britain are diagnosed with breast cancer and a third wait longer than three months for treatment. The delay is partly due to women postponing going to a GP and partly to the wait between referral and a hospital appointment. If the total delay could be reduced to less than three months for all women, at least 500 lives could be saved, Imperial Cancer Research Fund experts say.
The importance of speed of treatment is a controversy that has raged for 90 years. Doctors have said a tumour takes years to grow from a single cell to a detectable lump and that a few extra months cannot make a difference to survival. The results of the first systematic review of 100,000 patients in 87 studies from around the world, by Michael Richards and colleagues at St Thomas' Hospital, challenges that assumption.
It comes as the Government delivers its pledge to shorten waiting-times for women with symptoms.
From yesterday a new NHS target requires that all women with suspected breast cancer referred by a GP should be seen by a specialist within two weeks.
The target is criticised by the authors of the second paper in The Lancet, which found delays of more than three months did not affect survival, and that those treated quickest (within a month) died soonest.
Richard Sainsbury and colleagues at the Huddersfield Royal Infirmary, who examined 36,000 cases in the northern and Yorkshire region, conclude that "the drive ... to be seen within 14 days will divert resources from other services. Resources should instead be directed to ensuring that all patients have access to [the best care]."
At a news conference organised by the research fund yesterday, Professor Richards challenged this finding on the basis that women treated quickest had the most serious disease and were therefore most likely to die.
Mr Sainsbury, who was not invited to the news conference, said some studies included in Professor Richards's review were 70 years old. Too great an emphasis on speed of treatment would lead to clinics being overwhelmed and patients getting worse service.
Both experts conceded, however, that the Government is addressing only one aspect of delay - that caused by hospitals - while ignoring that caused by women themselves who fail to consult GPs promptly with symptoms. Delays in obtaining treatment were caused equally by patients and by hospitals.
The first sign is usually a lump in the breast, but other initial symptoms include changes to the nipple or dimpling of the breast. This list is used by specialists in south-east London:
r Breast lump in a woman over 25
r Persistent nodularity (lumpiness) in a woman over 30
r Blood-stained nipple discharge with a lump in a woman of any age
r New appearance of dimpling of the breast (not present from birth)
r New nipple inversion on one side
r Persistent nipple ulceration or eczema
r Persistent infection in the breast (in a woman who is not breast-feeding)Reuse content