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Ajouté le : 01 janvier 2000
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2 Futureof breast cancer services M Richards
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3/4 TheSwedish TwoCounty Trial 20years on: updated mortality results and new insights from long term followup † ‡§ # L Tabr*, SW Duffy , B Vitk , HH Chenand UB Krusemo *Department of Mammography, Central Hospital, Falun, Sweden;Biostatistics Unit, Medical Research Council, Cambridge, UK; ‡ § Department of Medical Radiology, University Hospital of Linkping, Linkping, Sweden;Institute of Epidemiology, College of # Public Health, National Taiwan University, Taipei, Taiwan andInformation Technology Support Department, Uppsala University,
The Swedish TwoCounty Trial is a randomized controlled study of invitation to breast cancer screening. It was initiated in late 1977. The followup to the end of 1998 provides results at approximately the twentieth anniversary of the trial. A significant decrease in breast cancer death among women invited to screening was published 7–8 years after randomization and at 20year follow up there is a significant 32% reduction in mortal ity associated with invitation to screening. The advent of screenfilm mammographic screening with the ability to detect potentially fatal tumors at an early stage provides an opportu
phase in its development than was possible in the past. Our findings show that breast cancer is not a systemic disease at its inception, but is a progressive disease and its development can be arrested by screening. Detection of <15 mm and lymph node negative invasive tumors will save lives and confer an opportunity for less radical treatment.
Mammography is clearly a very useful tool, not only for early detection of cancers but also for successful discrimination between the highly fatal and nonfatal cancers. The four
5 Screeningand its effect on breast cancer mortality rates RG Blanks
In the Health of the Nation document published by the Depart ment of Health in 1993 it was stated that the eventual success of the breast screening programme would be measured in terms of the breast cancer mortality reduction achieved. Unfor tunately, outside the environment of randomised controlled trials the actual mortality reduction from screening is extremely difficult to measure with any precision. This is because national mortality statistics between the start of screening in 1988 and the present day have been affected not only by screening, but also by treatment improvements, cohort effects, earlier presen tation outside the screening programme and even changes in the way breast cancer deaths are coded.
Additionally, the full effect of screening in national statistics is not likely to be achieved until 2005–2010 rather than the year
2000, as often reported. This is because of two major factors. Firstly, many deaths from breast cancer in the 1990s will be from women who were diagnosed with breast cancer before invitation to screening (full coverage was not achieved until 1995). Secondly, the screening sensitivity of the NHSBSP did not achieve parity with the SwedishTwo County study until 1996/97. In the early years of screening there was a major shortfall of invasive cancers, which led to high interval cancer rates and a projected mortality reduction much less than 25%. The combination of these two factors will lead to a consider ably lower mortality reduction than 25% by the year 2000. Nevertheless some mortality reduction from screening would be expected and standard epidemiological techniques (age cohort modelling) have been employed in an attempt to measure this.
6 IntroducingMRI into clinical breast practice S Field
Although there are numerous publications regarding the value (and limitations) of MRI in the diagnosis of a variety of breast conditions, access to MRI in the UK is severely limited.
7 MRguidedbreast biopsy SH HeywangKbrunner, H Sittek, X Prat and L Baath
MRI is capable of detecting small malignancies or malignant foci not visible by other methods. However, its specificity is limited. In order to render workup of MRdetected lesions as costeffective and as minimally invasive as possible, percuta neous MRguided biopsy is desirable.
So far various biopsy coils for imaging and fixation of the breast during percutaneous biopsy have been developed. However, MRguided core or fine needle biopsy has so far been limited to few cases mainly with lesions >1 cm.
An overview will be given over the presently available equip ment and techniques for percutaneous core needle biopsy.
8 Lymphnode diagnosis RE Mansel
Lymph node involvement remains the most powerful individual prognostic factor in breast cancer. Conventional axillary staging is either by axillary node clearance or some form of sampling. BASO data show that around onethird of surgeons in the UK are sampling and twothirds performing some type of clearance. The exact definition of clearance is not well defined and surgeons have different techniques. Evidence does suggest that, although lymph node sampling is qualita tively similar to clearance, the morbidity is little different, if the sample nodes prove positive and treatment is completed by radiotherapy to the breast and axilla. In view of these facts there is now enormous current interest in the technique of
The first aim is to establish a definitive diagnosis to ensure that the patient has a single operative procedure. The roles of FNA
only those that will lead to a clear alteration in clinical manage ment can be justified. Against this background, the current use of MRI in a busy symptomatic and screening practice will be
Furthermore, MRguided vacuum biopsy will be presented. It allows percutaneous biopsy of an area of up to 15 mm diame ter and thus can compensate for inaccuracies which might occur during needle insection or due to field distortion. Further more, in most cases disappearance of the enhancing lesion or visualisation of the cavity directly after the procedure allows us to directly prove representative removal.
Firstyear results of a multicentre study on MRguided vacuum biopsy will be shown as well.
Conclusion:MRguided vacuum biopsy promises accurate and reproducible workup of MRdetected lesions.
(draining node – a socalled sentinel node). The technique, which is best performed by a combination of radioisotope and blue dye, has been shown to detect a lymph node about 95% of the time and the false negativity varies from an average of 5% up to 30%. Current trials are taking place in the USA, Europe and the UK, looking at sentinel node biopsy in the breast cancer setting. The British trial, ALMANAC, is just com pleting the audit phase where each surgeon carries out 40 sentinel nodes biopsies, followed by a full axillary clearance or sampling. This has shown an acceptably low falsenegative rate and the main randomised portion of the trial is just begin ning. This will compare sentinel node biopsy alone against
and core biopsy will be considered. Cytology can be reported immediately, but core biopsy can establish a diagnosis of inva
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