Cancer diagnosis

I refer to Professor Albert Cilia Vincenti's letter (The Sunday Times, July 15) in reply to Part 2 of my article entitled "Cancer patients deserve to know the facts" (The Sunday Times, July 8).

Although Professor Cilia Vincenti rightly points out the prohibitive expenses involved in buying and maintaining PET scanners, as well as the logistical problems involved in the transport of constant radioactive material, he acknowledges the value of such scanners as being "superior to other scanners in certain diagnostic situations". Unfortunately, he prefers not to commit himself on whether the government should have purchased a state-of-art PET scanner that goes with a state-of-the-art Mater Dei Hospital.

As a pathologist, Professor Cilia Vincenti rightly speaks with authority about "the crucial importance and pitfalls of pathological cancer diagnosis". His comments about young patients who "have been subjected to limb or breast amputations, or to extensive radiotherapy and chemotherapy, for what were in reality non-cancerous conditions" are quite disturbing.

As I see it, his evidence supports the argument I adopted: "In essence, what this means is that some people who are misdiagnosed are being under-treated or mistreated; therefore, cancers that are curable are sometimes left untreated because they are considered incurable, while some people are being over treated and given drastic treatments where none was needed".

Professor Cilia Vincenti seems not at all impressed by Dr Ralph Moss's views on mammography. In my view, one need not be a medically qualified scientist to speak with authority on mammography or other related medical matters. As I stated in my article, Dr Moss's writings have been lauded by such experts as Dr William R. Fair, formerly chair of Urologic Oncology at Memorial Sloan-Kettering Cancer Centre, and Dr Harold P. Freeman, past national president of the American Cancer Society.

Professor Samuel Epstein, professor emeritus of Environmental and Occupational Medicine at the University of Illinois School of Public Health, and chairman of the Cancer Prevention Coalition, reviewed the report on mammography I cited and had this to say: "Unquestionably the world's leading authority on alternative and complementary medicine, Dr Ralph Moss, has already done more than any other to bring to public attention the risks and lack of efficacy of standard cancer treatments such as chemotherapy and radiation. His works on the politics of cancer and the hazards and biases of clinical trials have made him a recognised leader in the field of cancer policy analysis.

Now he turns his attention to the highly contentious field of breast cancer detection. The result is a characteristically thoughtful and incisive work that not only exposes the very real dangers of breast cancer screening - over 10 years of routine mammography a pre-menopausal woman receives almost half as much radiation as was measurable within a mile of the epicentre of the Hiroshima atom bomb explosion - but also lays bare the astonishing lack of scientific evidence underpinning current screening recommendations. This is an outstanding and important work by an outstanding and important author".

Professor Cilia-Vincenti states that the majority view around the world is that currently mammography is the best general purpose breast screening test (combined with ultrasound) we have got. This is certainly not the opinion of Christiane K. Kuhl, Professor of Radiology and vice-chair at the Department of Radiology, and director of the Division of Oncologic Imaging and Interventional Therapy at the University of Bonn. During the recent ASCO (American Society of Clinical Oncology) congress, the paper of Professor Kuhl and her colleagues, published on June 20, has been selected as 'Best of ASCO'. The paper states, among other findings: "MRI is far more efficient than mammography and ultrasound - also for women who are only at moderate risk of developing cancer".

Professor Cilia-Vincenti further states: "Whether a cancer screening test is any good is measured by how much it reduces mortality from that cancer, and mammography has been proven to do that not only by old Swedish and American trials, but more recently in the British NHS, which has one of the most organised national breast screening programmes in the world". It would have helped has Professor Cilia-Vincenti provided readers with the sources of his information.

My readings into this matter lead me to believe that that there still is no consistent, substantial scientific evidence that regular mammography screening results in a significant reduction in mortality for breast cancer. In an important paper published in 2000 in the prestigious British journal Lancet, Swedish researchers, working on behalf of the international Cochrane Review organisation, reviewed the quality of the major mammography trials to date and came to the following conclusions:

"Screening for breast cancer with mammography is unjustified. If the trials are judged to be unbiased, the data show that for every 1,000 women screened biennially throughout 12 years, one breast cancer death is avoided whereas the total number of deaths is increased by six." (Gotzsche 2000). Furthermore, according to Professor Cilia-Vincenti: "Whether or not, and how fast or slow, cancer cells spread is determined by their "computer programme" inside their altered DNA, and not by breast compression or palpation". I would be interested to learn what happens when this "computer programme" is disturbed by agents and events which cause or facilitate genetic changes in cells destined to become cancer.

In his mammography report, Dr Moss provides the following quotation from studies carried out by Dr Judah Folkman and Dr Michael Retsky: "Working alongside Professor Folkman, Dr Michael Retsky and other researchers have studied the question of the mammography paradox and have suggested that not only is the removal of the primary tumour the spur to proliferation of dormant metastases, but also that surgery itself, by creating a physical wound, independently triggers the release of growth factors that, in addition to assisting healing of the surgical wound, also promotes tumour growth. This effect is particularly marked in younger women with nod-positive disease".

As I understand it, the mammography paradox suggests that mammography in younger women (ages 40-49) may actually accelerate, rather than reduce, breast cancer mortality.

It was certainly not my intention to knock mammographic screening, as Professor Cilia-Vincenti explicitly states. Nor did I extol the merit of breast self-examination (BSE) and clinical breast-examination (CBE). Certainly, I did not even remotely suggest or prove in my article that BSE and/or CBE, on their own, actually reduce breast cancer mortality.

As I stated in my article: "Moss offers several alternatives and adjuncts to mammography in his report, including the use of thermography, Doppler ultra-sound, MRI and PET. He believes that the role of breast self-examination (BSE) and clinical breast examination (CBE) should not be underestimated or downplayed".

As he put it in his report, Dr Moss is not "advocating... the wholesome abandonment of screening mammography, but its more rational application; it is one tool that has several very real drawbacks, including repeated exposure to ionising radiation, and a high false positive (and false negative) rate. It makes sense, therefore, to incorporate other, less potentially damaging, detection techniques into one's prevention program, reducing one's reliance on frequent mammography...

While I do not want to discourage women from being screened for breast cancer - to the contrary, I believe that vigilance and early detection are extremely important - I do feel that it is vital for women to have a full understanding of the procedure and realistic expectations as to what it can, and cannot, do. This is the true basis of informed consent".