Mastectomies 'unnecessary', say key breast cancer studies

One of the tenets of breast cancer treatment is undermined today with the publication of two definitive studies showing that mastectomy – total removal of the breast – is unnecessary for most women.

The mutilating surgery, which can have damaging psychological consequences, has been regarded as the safest way of dealing with breast cancer for 80 years but had never been subjected to scientific tests.

Now American and Italian scientists who conducted a 20-year study of patients treated in the 1970s and 1980s have shown there is no difference in survival between those who had mastectomies and those who had smaller operations just to remove the tumour.

The results, published in the New England Journal of Medicine, should lay to rest the belief, still prevalent among some surgeons, that mastectomy is the best option for women. It will also lend weight to women in the UK who are taking legal action against surgeons for performing mastectomies unnecessarily.

A total of 51,000 breast cancer operations were performed in England in 2000-01, 15,000 of which involved mastectomy.

Michael Dixon, consultant breast surgeon at Edinburgh Royal Infirmary, said there were wide variations in mastectomy rates in different parts of the country that could not be accounted for by differences in the women affected. In 1999, the highest rate was in Yorkshire where 27 per cent of women with early breast cancer (a tumour up to 1.5cm in size) had mastectomies and the lowest was in Wessex where 12 per cent had the surgery.

Mr Dixon said: "A surgeon who advises a woman with breast cancer to have a mastectomy without making it clear why and offering her the choice of breast conserving surgery could face legal action for negligence." Several legal cases were pending, he said, and one had been settled out of court with the woman receiving compensation.

Mr Dixon said some women, such as those with two tumours in the breast or with a large area of pre-cancer, required mastectomy. But the variation revealed in the 1999 figures was "unacceptable", although it had improved since.

Dr Stephen Duffy, breast cancer epidemiologist for Cancer Research UK, said the main treatment centres in the UK accepted mastectomy was unnecessary for most but there were still some "more cautious and conservative" surgeons.

"My impression is that mastectomy probably still is overused but not to the extent that it was 10 years ago and nothing like the way it was used 20 years ago," he said.

The US and Italian trials, involving a total of 2,500 women, found that recurrence of cancer was slightly greater in women who had lumpectomies (local removal of the tumour) but it did not affect survival. Modern techniques of chemotherapy and radiotherapy mean local recurrence is now less likely.

In an editorial in the New England Journal, Monica Morrow, a breast cancer specialist at the Northwestern University Medical School in Chicago, describes the trials as "pivotal" and says they should convince "even the most determined sceptics that mastectomy is not superior to breast conservation."

She adds: "A reasonable goal is that every woman should be informed of the availability of breast conserving surgery and of the suitability of the procedure in her particular case ... It is time to declare the case against breast conserving therapy closed."

* The most important risk factor for breast cancer is old age but only 13 per cent of the population realise that, a Mori poll for the Breakthrough Breast Cancer charity shows. About 80 per cent of breast cancers occur in women over 50 but most respondents thought family history was more important.