Dr. Maureen Roberts was the clinical director of The Edinburgh Breast Screening Project from 1979 until her death from breast cancer in June 1989. Her letter appeared in The British Medical Journal after her death.

She poses the question: "What can screening actually achieve? Two randomized trials, The Health Insurance Plan and the Swedish two county trail, showed a reduction in mortality [death rate] of 30 percent in women offered screening. Other trials such as the Malmo, United Kingdom and Edinburgh trails found a non-significant reduction in mortality. We cannot ignore them and it is not enough to say that our techniques were not good enough a few years ago but are adequate now. We all know that mammography is an unsuitable screening test, it is technologically difficult to perform, the pictures are difficult to interpret, it has a high false positive rate, and we don't know how often to carry it out. We can no longer ignore the possibility that screening may not reduce mortality in women of any age, however disappointing that may be."

Dr. Roberts suggests that the final decision should be left to women and that:

"A truthful account of the facts be made available to the public and the individual patient. It will not be what they want to hear. They should be told that the test is to detect breast cancer while it is still small; that we don't know how much it can influence mortality, but there is a 30 percent chance (though maybe much less) that it may prolong life; that the test does not detect all cancers, some of which may appear between screenings, and that it cannot predict whether breast cancer will develop in the future. In addition, we do not know how to treat breast cancer. There is no successful treatment; different surgeons will carry out different procedures... (Those with normal mammograms) can feel suitably reassured except that they must remember that they can develop the disease at any time; screening is not prevention."

Another View

Dr. Robert's colleague Dr. Jocelyn Chamberlain in a response to her letter says:

"During the next 20 years, I, in my late 50's stand a one in forty chance of dying from breast cancer. If screened from age 50 onward I may be able to reduce this risk to one in 55. To me this reduction is worth the slight inconvenience of going for a mammography every few years; of having a one in 14 chance of being referred and a one in 170 chance of having a benign biopsy (both of which have happened to me and were more irritating than alarming); and even of artificially increasing my chance of breast cancer diagnosis. On what evidence do you base your claim that "women will not want to hear" these facts and, by implication, will not want to avail themselves of the protection which screening offers? To me it seems a mildly inconvenient but sensible precaution in the same league, albeit at a greater cost, as a cholera or typhoid immunisation before a foreign trip. In summary, therefore, I believe that breast screening is good for women, though perhaps not for the taxpayer."

The Large Screening Program In Ontario

In Ontario, a 15 million dollar program for screening women over age 50 was started in August 1990. The objective of the program is to screen 70 percent of women aged 50 to 64 every two years until their 70th birthday. This project will involve an estimated 300,000 women per year.

Advocates of this program point out that 300 lives per year might be saved based on the studies mentioned above.

Dr. Aileen Clarke, Cancer Co-ordinator for the province of Ontario and chief of epidemiology at the Ontario Cancer Treatment and Research Foundation, points out in a July 1990 letter that:

"In the absence of an organized province wide program, women who will not benefit from mammography will receive mammography, possibly of a questionable quality, and women who would benefit from mammography (older and less likely to request screening) will not necessarily be aware of its value."

The number of mammograms done in Ontario, Dr. Clarke says, had risen from 70,000 in 1983 to 243,000 in 1989 at a cost of more than 12 million dollars.