• The Benefits and Harms of Breast Cancer Screening: An Independent Review

    The Lancet, Early Online Publication, 30 October 2012

    doi:10.1016/S0140-6736(12)61611-0Cite or Link Using DOI

    The benefits and harms of breast cancer screening: an independent review

    Original Text

    Independent UK Panel on Breast Cancer Screening

    Summary

    Whether breast cancer screening does more harm than good has been debated extensively. The main questions are how large the benefit of screening is in terms of reduced breast cancer mortality and how substantial the harm is in terms of overdiagnosis, which is defined as cancers detected at screening that would not have otherwise become clinically apparent in the woman’s lifetime. An independent Panel was convened to reach conclusions about the benefits and harms of breast screening on the basis of a review of published work and oral and written evidence presented by experts in the subject. To provide estimates of the level of benefits and harms, the Panel relied mainly on findings from randomised trials of breast cancer screening that compared women invited to screening with controls not invited, but also reviewed evidence from observational studies. The Panel focused on the UK setting, where women aged 50—70 years are invited to screening every 3 years. In this Review, we provide a summary of the full report on the Panel’s findings and conclusions. In a meta-analysis of 11 randomised trials, the relative risk of breast cancer mortality for women invited to screening compared with controls was 0·80 (95% CI 0·73—0·89), which is a relative risk reduction of 20%. The Panel considered the internal biases in the trials and whether these trials, which were done a long time ago, were still relevant; they concluded that 20% was still a reasonable estimate of the relative risk reduction. The more reliable and recent observational studies generally produced larger estimates of benefit, but these studies might be biased. The best estimates of overdiagnosis are from three trials in which women in the control group were not invited to be screened at the end of the active trial period. In a meta-analysis, estimates of the excess incidence were 11% (95% CI 9—12) when expressed as a proportion of cancers diagnosed in the invited group in the long term, and 19% (15—23) when expressed as a proportion of the cancers diagnosed during the active screening period. Results from observational studies support the occurrence of overdiagnosis, but estimates of its magnitude are unreliable. The Panel concludes that screening reduces breast cancer mortality but that some overdiagnosis occurs. Since the estimates provided are from studies with many limitations and whose relevance to present-day screening programmes can be questioned, they have substantial uncertainty and should be regarded only as an approximate guide. If these figures are used directly, for every 10 000 UK women aged 50 years invited to screening for the next 20 years, 43 deaths from breast cancer would be prevented and 129 cases of breast cancer, invasive and non-invasive, would be overdiagnosed; that is one breast cancer death prevented for about every three overdiagnosed cases identified and treated. Of the roughly 307 000 women aged 50—52 years who are invited to begin screening every year, just over 1% would have an overdiagnosed cancer in the next 20 years. Evidence from a focus group organised by Cancer Research UK and attended by some members of the Panel showed that many women feel that accepting the offer of breast screening is worthwhile, which agrees with the results of previous similar studies. Information should be made available in a transparent and objective way to women invited to screening so that they can make informed decisions.

  • Cancer prevention on minds of Ontario CWL

    Written by Erin Morawetz, The Catholic Register
    Wednesday, 25 July 2012 14:25

    Ontario’s Catholic Women’s League has put its support behind infrared breast screening thermography while expressing opposition to youth indoor tanning.

    These resolutions were passed at the 65th annual Ontario provincial convention of the CWL, which took place in Kingston, Ont., July 9 to 11.

    Marlene Pavletic, president of the provincial council, told The Catholic Register that each of the resolutions passed with little debate.

    “What we try to do is focus on the actual material, ensuring that we’ve got good Canadian material (that’s) current,” Pavletic said. “We’ve gone in depth to make sure our briefs are solid.”

    The first resolution, prepared by the St. Catharine’s Diocesan Council, looks at infrared breast screening thermography as an alternative to mammograms.

    “There is a concern about the extra radiation that women are getting from mammograms, and thermography doesn’t have any radiation,” Pavletic explained.

    This cancer detection treatment has not been approved in Ontario, but the council will now be insisting the Ontario Ministry of Health take another look.

    “We would like them to re-do some studies on it with the modern technology of thermography,” Pavletic said.

    For the second resolution, which was prepared by the Kingston council, the provincial council is joining many other advocacy groups pressing the government to prohibit the use of indoor tanning equipment by youth.

    “It’s a public health issue,” Pavletic said. “Our concern is that melanoma is one of the most serious cancers and the most common types of cancers.

    “We thought that if we could urge the government to prohibit the use of it before the age of 18, that might perhaps decrease the incidence of it.”

    Local MPP John Gerretsen was on hand to address the delegates at the opening ceremony. He said efforts like those of the Ontario CWL will slowly but surely make a difference.

    “I urged them to continue advocating,” he said. “One of the things that they’ve done over the last two or three years is have information sessions at Queen’s Park with members of all political parties, and I urged them to continue with that.”

  • TEN-YEAR RISK OF FALSE POSITIVE SCREENING MAMMOGRAMS AND CLINICAL BREAST EXAMINATIONS

    The New England Journal of Medicine
    ©Copyright, 1998, by the Massachusetts Medical Society
    VOLUME 338 A PRIL 16, 1998 NUMBER 16

    J OANN G. E LMORE , M.D., M.P.H., M ARY B. B ARTON , M.D., M.P.P., V ICTORIA M. M OCERI , P H .C., S ARAH P OLK , B.A., P HILIP J. A RENA , M.D., AND S UZANNE W. F LETCHER , M.D.

    A BSTRACT Background The cumulative risk of a false positiveresult of a breast-cancer screening test is unknown. Methods We performed a 10-year retrospective co-hort study of breast-cancer screening and diagnosticevaluations among 2400 women who were 40 to 69years old at study entry. Mammograms or clinicalbreast examinations that were interpreted as indeter-minate, aroused a suspicion of cancer, or promptedrecommendations for additional workup in women inwhom breast cancer was not diagnosed within thenext year were considered to be false positive tests. Results A total of 9762 screening mammogramsand 10,905 screening clinical breast examinationswere performed, for a median of 4 mammograms and5 clinical breast examinations per woman over the 10-year period. Of the women who were screened, 23.8percent had at least one false positive mammogram,13.4 percent had at least one false positive breast ex-amination, and 31.7 percent had at least one falsepositive result for either test. The estimated cumula-tive risk of a false positive result was 49.1 percent (95percent confidence interval, 40.3 to 64.1 percent) after10 mammograms and 22.3 percent (95 percent confi-dence interval, 19.2 to 27.5 percent) after 10 clinicalbreast examinations. The false positive tests led to870 outpatient appointments, 539 diagnostic mam-mograms, 186 ultrasound examinations, 188 biopsies,and 1 hospitalization. We estimate that among wom-en who do not have breast cancer, 18.6 percent (95percent confidence interval, 9.8 to 41.2 percent) willundergo a biopsy after 10 mammograms, and 6.2 per-cent (95 percent confidence interval, 3.7 to 11.2 per-cent) after 10 clinical breast examinations. For every$100 spent for screening, an additional $33 was spentto evaluate the false positive results.

    To read the rest of the study, click here to download the PDF.

  • Screening for Breast Cancer

    JAMA. 2005 Mar 9;293(10):1245-56.

    Screening for breast cancer.

    Elmore JG, Armstrong K, Lehman CD, Fletcher SW.

    Source

    Department of Medicine, University of Washington School of Medicine, Seattle, USA. jelmore@u.washington.edu

    Abstract

    CONTEXT:

    Breast cancer screening in community practices may be different from that in randomized controlled trials. New screening modalities are becoming available.

    OBJECTIVES:

    To review breast cancer screening, especially in the community and to examine evidence about new screening modalities.

    DATA SOURCES AND STUDY SELECTION:

    English-language articles of randomized controlled trials assessing effectiveness of breast cancer screening were reviewed, as well as meta-analyses, systematic reviews, studies of breast cancer screening in the community, and guidelines. Also, studies of newer screening modalities were assessed.

    DATA SYNTHESIS:

    All major US medical organizations recommend screening mammography for women aged 40 years and older. Screening mammography reduces breast cancer mortality by about 20% to 35% in women aged 50 to 69 years and slightly less in women aged 40 to 49 years at 14 years of follow-up. Approximately 95% of women with abnormalities on screening mammograms do not have breast cancer with variability based on such factors as age of the woman and assessment category assigned by the radiologist. Studies comparing full-field digital mammography to screen film have not shown statistically significant differences in cancer detection while the impact on recall rates (percentage of screening mammograms considered to have positive results) was unclear. One study suggested that computer-aided detection increases cancer detection rates and recall rates while a second larger study did not find any significant differences. Screening clinical breast examination detects some cancers missed by mammography, but the sensitivity reported in the community is lower (28% to 36%) than in randomized trials (about 54%). Breast self-examination has not been shown to be effective in reducing breast cancer mortality, but it does increase the number of breast biopsies performed because of false-positives. Magnetic resonance imaging and ultrasound are being studied for screening women at high risk for breast cancer but are not recommended for screening the general population. Sensitivity of magnetic resonance imaging in high-risk women has been found to be much higher than that of mammography but specificity is generally lower. Effect of the magnetic resonance imaging on breast cancer mortality is not known. A balanced discussion of possible benefits and harms of screening should be undertaken with each woman.

    CONCLUSIONS:

    In the community, mammography remains the main screening tool while the effectiveness of clinical breast examination and self-examination are less. New screening modalities are unlikely to replace mammography in the near future for screening the general population.

  • Mammograms Over 40: Surprise? Half Of Women Over Are Skipping Them

    MARILYNN MARCHIONE | 12/ 9/10 11:07 AM |

     Read More: Breast Cancer, Breast Cancer Mammogram, Breast Mammogram, Breast Screening, Mammogram Over 40, Mammogram Over 50, Mammogram Recommendations, Mammogram Test, Mammograms, Health News

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    SAN ANTONIO — Remember the uproar last year when a government task force said most women don’t need annual mammograms? It turns out that only half of women over 40 had been getting them that often to start with, even when they have insurance that covers screening.

    The information comes from a review of insurance claims that show what women actually do – not what they say in surveys.

    “We all support many things – fast food isn’t what we should eat for dinner every night – but that isn’t what we do,” said Dr. Milayna Subar of Medco Health Solutions Inc., which manages benefits for many large insurers, including some Medicare plans.

    She did the study, using records on more than 1.5 million women, and reported results Thursday at a breast cancer conference.

    The finding is disturbing, said Dr. Judy Garber of Dana-Farber Cancer Institute in Boston and president-elect of the American Association for Cancer Research, one of the conference’s sponsors. “Here’s an insured population where cost is not a barrier,” and yet many women are not getting tested. [Read More…]

  • Cruel Wait Not Breast Practice

    • Robyn Riley
    • From: Sunday Herald Sun
    • April 11, 2010 12:00AM
    • 18 comments

    I AM no doctor, but as someone who was a medical writer for many years, I consider myself reasonably well informed on medical matters.

    But I did not know that BreastScreen Australia provided a screening mammogram only – not a diagnostic mammogram.

    There is a big difference, as I found out last week.

    A screening mammogram is only for women who do not present with symptoms. So the first thing to remember is that anyone with symptoms – and that can be anything from a lump to a discharge or even changes in colour – should not use the free BreastScreen program.

    They should have a GP refer them for a diagnostic mammogram.

    Why? Because it can save you several weeks of worrying. A diagnostic mammogram is also more specific and the results can be returned within a day. [Read More…]

  • Concerns About Recommending Routine Screening Mammograms for Women Age 40 to 49

    By Jacquelyn Paykel and William H. Wolberg 

    The controversy concerning the usefulness of screening mammography in younger-than-50 women continues. In general, two factors are consistently overlooked that should bear heavily on screening recommendations, particularly as they pertain to national policy. First, understanding why screening is more beneficial after as opposed to before age 50; second, assessing the societal cost of routine screening in younger women. 

    Pivotal to this discussion – and unavailable from any of the current studies – is the menopausal status of the patients being screened. Biological age is more important than is chronological age. At the time of menopause, the ovaries cease to produce estrogen. Lacking bodily estrogen, the breast glandular tissue involutes, and cancerous nodules become more apparent by mammogram. Therefore, screening is going to be as advantageous to a woman who is postmenopausal at age 48 as it is to a woman at age 55 or older. The reported screening studies have been conveniently designed based on the subjects’ date of birth (age), rather than on the appropriate standard which is the menopausal status of the subject. Furthermore, women who started to receive mammograms before age 50 continued to receive them after their fiftieth birthday. Not only was the menopausal status ignored, but any beneficial effect of screening before 50 could not be distinguished from that occurring after 50. 

    Some otherwise undetectable cancers are found by mammography in younger-than-50 women. Women in this age group who have been mammographically diagnosed become strong advocates for screening. However, the radiation given with mammograms undoubtedly causes some cancers particularly in younger women when the breast is under estrogen stimulation. What is unclear is whether mammograms result in curing more cancers than they cause in this age group. The available data indicate that there is a close trade off.  [Read More…]