Efficacy Of Breast Cancer Screening Research Articles

An Integrative Review on Breast Cancer Screening Practice and Correlates Among Chinese, Korean, Filipino, and Asian Indian American Women

Breast cancer is the leading cancer diagnosed among Chinese, Filipino, and Korean women. Despite the efficacy of breast cancer screening, Asian American women have one of the lowest rates of mammography and clinical breast exam (CBE) of all U.S. ethnic groups. I provided a systematic overview to document factors related to three modalities of breast cancer screening (breast self-exam [BSE], CBE, and mammography) among four subgroups of Asian American women (i.e., Chinese, Korean, Filipino, and Asian Indian). Results showed that the existing studies provided evidence of demographic correlates to screening practice; however, fewer studies focused on cognitive and social–cultural correlates, and limited results were available with Filipino and Asian Indian groups.

超音波検査による乳癌検診の有用性について―１０年間の成績―

超音波検査による乳癌検診の有用性について―１０年間の成績―

The use of magnetic resonance imaging in breast cancer screening

Screening mammography is a powerful tool for reducing breast cancer mortality. Mammography can often detect clinically occult, early-stage breast cancer that is amenable to successful treatment. However, mammography is not a perfect test and has lower sensitivity in young women and in those with dense breasts. Magnetic resonance imaging (MRI) has been shown to depict breast cancers that are occult to other forms of detection, including mammography. This has generated interest in the use of MRI for breast cancer screening. Although preliminary studies in highly selected populations show promise for the potential efficacy of breast cancer screening with MRI, there are many questions that should be addressed before this technique is offered to the general population.

Attitudes to prophylactic surgery and chemoprevention in Australian women at increased risk for breast cancer.

Because of the uncertain efficacy of breast cancer screening in women at increased risk of developing breast cancer, bilateral prophylactic oophorectomy and mastectomy are considered management options for high-risk women. Data on the attitudes to prophylactic strategies of high-risk women who have not attended specialist clinics are needed to ascertain the need for patient education and provide the basis for planning of support services. Three hundred seventy-one women unaffected by cancer and with unknown mutation status from families with a dominantly inherited susceptibility to breast cancer, recruited through a large Australian population-based, epidemiological study, were assessed using a mailed self-administered questionnaire with validated measures of psychological outcome. Sixteen percent of women reported considering prophylactic mastectomy, and 1% had already had the procedure. Among women with a family history of breast/ovarian cancer, 33% had considered and 5% had already had a prophylactic oophorectomy. Twenty-three percent of women reported considering taking tamoxifen if it were shown to prevent breast cancer. Consideration of prophylactic oophorectomy (OR = 1.51 for a 10% change in perceived risk, 95% CI 1.14-1.99, p = 0.0045) and tamoxifen (OR = 1.14 for a 10% change in perceived risk, 95% CI 1.002-1.30, p = 0.047) were positively associated with perceived cancer risk. Attitudes to prophylactic surgery and psychological distress levels in high-risk women participating in an epidemiological study appear to be comparable to those of women attending familial cancer clinics and indicate that women attending high-risk clinics may be representative of the larger population of women at increased risk.

Expert Group: IARC Handbooks of Cancer Prevention. Vol.7: Breast Cancer Screening. Lyon, France: IARC; 2002. 248pp.

The latest publication in the International Agency for Research on Cancer's (IARC) series of Handbooks of Cancer Prevention is focused on breast cancer screening. The monograph is the outcome of a weeklong meeting of the Working Group on the Evaluation of Cancer-Preventive Strategies that took place in Lyon, France, March 5–12, 2002. The decision to produce a handbook on breast cancer screening was timely for several reasons. First, only a few monographs exist that focus exclusively on breast cancer screening, none of which represent a comprehensive treatment of the subject, and all were published before 1990 [1-4]. Second, the value of breast cancer screening recently had been challenged by a Cochrane Review [5] on screening for breast cancer with mammography, and a number of independent expert groups had been assembled to evaluate that analysis and the authors' provocative conclusions. Thus, in the presence of another expert group's conclusion that there was no scientific evidence to support the value of mammography, the IARC Working Group's evaluation of the world's literature on the efficacy of breast cancer screening had an extra dimension of drama. Contrary to the Cochrane Review, the IARC Working Group affirmed the value of mammography for women aged 50–69. Anyone interested in breast cancer control, or screening in general, will find this volume a valuable addition to their library. The book is well organized, and proceeds through the evaluation of the scientific evidence in the context of the classic criteria for principles and practices of screening for disease established by Wilson and Junger in 1968 [6]. Chapters one through three describe the global burden and the natural history of breast cancer, conceptual considerations related to screening performance, various methods of early detection, including conventional and experimental imaging techniques as well as physical exams, and use of screening and behavioral issues related to screening uptake. Chapters four through six review conceptual issues and the existing evidence on efficacy, effectiveness, and cost-effectiveness of screening. The monograph concludes with a summary chapter, an additional chapter with a brief description of the conclusions, and another on recommendations for future research. Thus, the monograph provides the most extensive treatment available of the issues pertaining to breast cancer screening. It concludes that mammography is effective in reducing breast cancer mortality, but like other screening tests, has a number of limitations. Undoubtedly, those who are familiar with the literature will see some topics that are treated with a degree of certainty that belies the limitations of the existing data, or the presence of alternative interpretations. If one accepts the results from the trials uncritically it is reasonable to conclude that there is limited evidence to support the efficacy of screening women aged 40–49. However, the poor performance of screening in the trials in this age group must be seen as the result of screening intervals that were too wide to achieve a measurably reduced incidence rate of advanced disease. Considerable inferential evidence from the trials [7], meta-analyses [8,9], and evaluations of service screening [10-12] support the conclusion that, when women in their forties are screened at a 12–18 month interval, mortality reductions are equivalent to those that can be expected in women aged 50+ screened every 24 months. Another example of a conclusion that has limited supporting evidence is the assertion that 5–25% of cancers detected by mammography represent over-diagnosis. While it has been estimated that some over-diagnosis exists, the overall proportion likely is less than 5%, of which most occurs during a prevalent screen. In subsequent incident screens the rate is very small to nonexistent [13,14]. Like many areas of research, experts can and will differ in the conclusions they draw from existing evidence. Still, the IARC Handbook on Breast Cancer Screening has much to offer, and will be required reading for anyone with an interest in screening, and especially an interest in breast cancer screening.

Study design of randomized controlled clinical trials of breast cancer screening.

Evaluation of population screening must be based on a randomized clinical trial (RCT) with the study population randomized into two arms: an intervention group invited to screening and a control group not invited to screening. Reduced mortality in the intervention group is evidence of a benefit from screening. Individual randomization is the ideal, but cluster randomization is often used for logistical and ethical reasons. The use of volunteer subjects is methodologically acceptable, but results cannot be generalized. Seven RCTs of breast cancer screening by mammography have been carried out in the United States, Canada, Sweden, and Scotland. All the studies, except the Canadian, were designed to assess the effect of screening across a wide range of ages at entry. The question of the efficacy of breast cancer screening at younger ages (< 50 years) arose early, after the first results were reported. To address this question, basic elements of the screening protocol must be considered when interpreting the results; these are screening modality (e.g., mammography with or without physical examinations), interscreening interval, and number of screening rounds. This article examines the possible influence of these factors and reviews the design choices and the characteristics of the seven RCTs.

Breast cancer screening in premenopausal women: current recommendations and opportunities for research.

The American Cancer Society recommends periodic mammography, clinical breast examination and breast self-examination beginning at age 40 years for asymptomatic women at average risk of breast cancer. Although there is substantial evidence from meta-analyses and non-randomized studies to support these recommendations, individual randomized clinical trials of breast cancer screening have not demonstrated mortality reduction in women aged 40-49 years. The opportunity to study this issue further in the United States has been diminished by the high prevalence of screening already being conducted in that population of younger women. The International Union Against Cancer, the American Cancer Society and the National Cancer Institute of the United States have convened a series of workshops and planning meetings to consider the available data and outline plans for future research. Plans are being developed to conduct a randomized trial of mammography in women younger than 50 years in multiple European sites. Successful completion of this trial may provide critical data on efficacy of breast cancer screening in younger women.

A model-based prediction of the impact on reduction in mortality by a breast cancer screening programme in the city of Florence, Italy

The efficacy of breast cancer screening for women older than 50 years has been shown in several studies. Service screening is now ongoing or planned in several countries in Europe. MISCAN, a computer simulation programme, has been used to analyse data from the Florence District Programme (FDP) breast cancer experience. First, the model was fitted to the screening results for the period 1975-1986. A good correspondence between the model outcomes and the FDP results was achieved. It was then used to predict the impact on mortality of the new starting programme of the city of Florence (63,000 women, 50-69 years old). Assuming a 70% attendance rate, then for the city of Florence, 2563 screen-detected breast cancers are predicted for the period 1991-2020 out of the total number of 9095 breast cancers for all ages (28%). A total of 3720 deaths for breast cancer are expected without screening. An absolute reduction of 472 deaths (13%) is predicted for the whole population. The estimated number of years of life gained by screening until 2020 is 4354. Simulation by MISCAN has previously been a useful support tool for decision-making about screening. The present paper is the first based on a southern European experience. The possibility of applying MISCAN to predict the impact of a national programme in Italy is discussed.

Case-Control Evaluation of Breast Cancer Screening Efficacy

The feasibility and validity of using case-control methods to evaluate the efficacy of breast cancer screening were investigated using data from the Health Insurance Plan of Greater New York Breast Cancer Screening Trial. Women who died of breast cancer were compared with individually matched controls of the same age who had equal or greater survival times. To minimize the effects of self-selection bias, most analyses focused on the 95 cases and 380 matched controls who had been screened at least once and for whom covariate data were available. A statistically significant effect for being screened more than once versus being screened once, uncorrected for healthy-screenee bias, was found (odds ratio = 0.13, p less than 0.001). After correction for healthy-screenee bias, the effect was not statistically significant (odds ratio = 0.54, p = 0.15). Possible explanations for this statistical nonsignificance are: 1) correction for healthy-screenee bias entails loss of power and 2) the correction procedure used may, under some circumstances, result in bias toward the null hypothesis. Further research into means of eliminating healthy-screenee bias is needed to improve the applicability of case-control methods to the evaluation of screening efficacy.

Ten- to Fourteen-Year Effect of Screening on Breast Cancer Mortality&lt;xref ref-type="fn" rid="fn2"&gt;2&lt;/xref&gt;

Results from the randomized trial conducted by the Health Insurance Plan (HIP) to determine the efficacy of breast cancer screening with mammography and palpation are reported for longer periods than previously available. By the end of 10 years after entry, the study group's mortality due to breast cancer was about 30% below the control group's. Arithmetic gains due to screening were maintained through year 14; relative gains declined. With increases in the period of follow-up, cumulative survival rates among cases detected by mammography alone (palpation negative during screening), decreased more rapidly than rates among other subgroups, but survival rates for mammography cases remained relatively high. Study women aged 40-49 years at entry began to show lower breast cancer mortality than those in the control group as duration of follow-up increased. Reservations are advanced about the acceptance of this finding as evidence of the efficacy of screening under age 50 under the conditions of the HIP study. The reservations are based on the observation that the decrease of mortality among the study group aged 45-49 at entry is concentrated entirely among cases diagnosed after they reached 50 years of age.