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A new way in breast cancer clinical primary prevention.
- Sergio Stagnaro (27 August 2004)
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alternatives
- lee levine (28 August 2004)
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Confounding factors in the Million Women Study?
- Victor A. Palmer (28 August 2004)
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The Million Women Study: what's in the name?
- A Cecile JW Janssens, Ewout W Steyerberg (28 September 2004)
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Sergio Stagnaro, Specialist in Blood, Gastroenterology, and Metabolic Diseases. Researcher in Biophysical Semeiotics. Via Erasmo Piaggio 23/8 16037 Riva Trigoso (Genova) Italy
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Sirs, As I wrote recently (as usual without receiving any response, of course) in an open letter to Italian Health Minister Prof Sirchia (See my Page Semeiotica Biofisica in the URL wwwkatamed http://www.katamed.it/Notizia.asp?idcat=999&ID=8094, in order to perform, on very large scale, an efficacious primary prevention against breast cancer, we must fortunately take into consideration a lot of knowledge, ignored or overlooked also by the paper's authors. Here my "unanswered" open letter: "To the italian Minister of the Health, Prof. Sirchia. As you know very well, the screening of the cancer does not coincide at all with the primary prevention of the malignancy: all SSN, in Italy as well as in all other countries of the world, have lead and lead, with remarkable expenses, "limited, fail to fulfill" and partially effective screenings for breast cancer, but never one true campaign of primary prevention on the entire, both male and feminine population: actually, also the male sex can be hit by breast cancer. In truth, for being able to realize successfully a primary prevention of a tumor between the most diffuse, which causes elevated mortality and suffering, the doctors and the competent sanitary authorities, must know the oncological constitution, i.e., the Oncologico Terrain, and the Oncological Real Risk (1, 2) (See web-site, HONCode 233736, www.semeioticabiofisica.it: Oncological Terrain), component of the Single Patient Based Medicines, suggested also from the Competent Authorities in "Planning for the EU Public Health Portal", web-site Europe Health Alliance, at the URL: http://europa.eu.int/comm/health/ph_information/documents/ev_20030710_co01_en.pdf. I write, Mr. Minister, this open letter on "clinical" primary prevention of breast cancer for two reasons principally: A) a 47 year-long clinical experience allows me to state that “clinical” primary prevention of breast cancer must unavoidably be preceded from rational selection of "all" individuals of both sexes, affected by Oncological Terrain "and" Oncological Real Risk in a mammary quadrant (or more, of course), recognizable and easily quantificated with the Biophysical Semeiotics. In fact, Mr. Minister, the absence of the Oncological Real Risk in the breast, in a subject with Oncological Terrain, excludes beyond every doubt the possibility of occurrence of breast cancer (1, 2); B) ever since I agree perfectly with following thought: "It is difficult to remove methods perfectly organized, having long tradition, supported from famous names also, based on an elegant, but wrong doctrinaire equipment; strong from political, economic, organizational, financial, pseudosocial view-point. We dare to face such as paramount problem in order not to feel in guilt towards ourselves, rather than in the conviction to succeed and to resolve,".(Luigi Di Bella: "Cancer: we are on the just way?". Editions Travel Factory Srl - Rome, 2001). The performance of this original intervention of primary prevention of breast cancer, surely other that expensive, but effectively involving "all" citizens with oncological real risk, need of the essential participation of General Practitioners, who play a role of primary importance. The various stages of this prevention can be, generally, established as
follows, awaiting obviously the definitive contributions by authorities
specialized in this type of operations concerning public health and by the
ethical committees; regarding eventually expectable objection, i.e., the
possible discrimination of the positive citizens for the Oncologico Land,
I, former-bearer of oncological constitution, put the question:” What does
it mean to spend huge sums of money in searches on the genetic code and the
mutations of "the single" DNA nuclear, in the light of such suspects
discrimination?
In such as prevention I am using Melatonina-Adenosina – tablet with 2
mgr and 9 mgr, respectively – two cpr before going to sleep, in average.
Due to personal physical conditions, in addition, and not only because of my age, surely I cannot allow me to participate actively to this prevention, to which I can only assure all the my "theoretical" contribution and of competence in the Biophysical Semeiotics. I thank you, Mr. Minister of the Health, for the kind acceptance. Best regards and greetings of All God. Sergio Stagnaro
Competing interests: None declared |
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lee levine, retired counselor n/a
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It would have been helpful to have provided information on what available alternative tests/options to mammograms there are for women in this cohort. Competing interests: None declared |
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Victor A. Palmer, Medical writer Saxthorpe Hall, Saxthorpe, Norfolk NR11 7DE
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The authors of the Million Women Study have countered criticism of their retrospective analysis of data from women voluntarily attending for mammography by pointing to the "power" of a study involving such very large numbers. Prof Stevenson and many others have noted that the increased risk for breast cancer detected in the MWS is equivalent to the known increased risk from being overweight.We now learn from the MWS authors that the sensitivity and specificity of mammography itself is reduced in women who have undergone previous breast surgery, in current or past HRT users and in underweight women. The reduction in sensitivity and specificity of mammography in underweight women and current or ever users of HRT appears to be statistically comparable. If the sensitivity of mammography is 'lower' in underweight women it must be 'higher' in normal or overweight women. (The authors cut off level of BMI >25 is in fact the NIH upper limit of normal, so their 'underweight' group actually includes both the clinically underweight and all women of normal weight.) In the MWS, the relative increase in risk for breast cancer was large ("HRT doubles the risk of breast cancer" as the tabloids put it). However the increase in absolute risk was small,0.5-0.7%. Since overweight is already accepted as an important risk factor for breast cancer and has now also been shown to increase the sensitivity of mammography, a slight difference in mean BMI between the ever and never users of HRT in the MWS is likely to have swamped any independent risk from HRT. This would not be compensated for by the fact that the small number of women who had undergone previous breast surgery are likely to have been over-represented in the never users group. It is also noteworthy that many women report weight gain as an unwanted effect of HRT. Finally does one detect an anti-HRT bias amongst the authors? Whilst the title of the study is "Influence of personal characteristics of individual women on sensitivity and specificity of mammography in the MWS cohort study", the authors state that patients were 'selected for a special study of the effect of HRT on mammographic sensitivity and specificity' Competing interests: None declared |
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A Cecile JW Janssens, Postdoc researcher Erasmus MC University Medical Center Rotterdam, department of Public Health, 3000 DR The Netherlands, Ewout W Steyerberg
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Banks et al. applied logistic regression to calculate the adjusted sensitivity and specificity of mammography for subgroups of women in the Million Women study. The adjusted sensitivity was obtained by the prediction of true positive screen results among women who developed breast cancer (n=726), and the adjusted specificity by the prediction of true negative screen results among women who did not develop breast cancer (n=121,629) within 12 months following screening. The actual sample size in the analyses, especially for the sensitivity, was thus by far lower than suggested by the name of the cohort. The strategy of separate analyses for the sensitivity and specificity may be statistically defendable but is rather inefficient. In this study, the separate analyses yielded substantially wider confidence intervals for the sensitivity than for specificity. This has implications for the conclusions about differences in sensitivity and specificity of mammography between subgroups. For example, the adjusted specificity of mammography screening was 97.2 in women with normal body mass index (<25) and 97.4 in those with high body mass index (>25). The difference of only 0.2 was highly significant (p=0.003). In contrast, the adjusted sensitivity among women with and without a first degree relative with breast cancer was 83.5 and 89.4, a difference of 5.9 that was not statistically significant (p=0.10). We have recently developed a regression approach to calculate the likelihood ratios of positive and negative test results1 which uses all available data simultaneously. The method can be used to calculate the sensitivity and specificity of a test for a particular patient risk profile that is determined by multiple patient characteristics. This is particularly useful when the study is not large enough for direct calculation of the sensitivity and specificity in subgroups of women. The mathematical derivation of this method supports the conclusion of Banks et al. that variation in sensitivity and specificity is due to the correlation between the test and other predictors of the underlying disease. 1. Janssens ACJW, Deng Y, Borsboom GJJM, Eijkemans MJC, Habbema JDF, Steyerberg EW. A new logistic regression approach for the evaluation of sequential diagnostic tests. Med Decis Making 2003;23:555 [abstract]. Competing interests: None declared |
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