The effect of the Flemish breast cancer screening program on breast cancer-specific mortality: A case-referent study

BackgroundBreast cancer screening programs were introduced in many countries worldwide following randomized controlled trials in the 1980s showing a reduction in breast cancer-specific mortality. However, their effectiveness remains debated and estimates vary. A breast cancer screening program was introduced in 2001 in Flanders, Belgium where high levels of opportunistic screening practices are observed. The effectiveness of this program was estimated by measuring its effect on breast cancer-specific mortality.MethodsWe performed a case-referent study to investigate the effect of participation in the Flemish population-based mammography screening program (PMSP) on breast cancer-specific mortality from 2005 to 2017. A multiple logistic regression model assessed the association between breast cancer-specific death and screening program participation status in the four years prior to (pseudo)diagnosis (yes/no), with adjustment for potential confounders (individual socio-economic position and calendar year of diagnosis) and stratified for age. In addition, we performed different sensitivity analyses.ResultsWe identified 1571 cases and randomly selected 6284 referents. After adjustment, women who participated in PMSP had a 51 % lower risk of breast cancer-specific mortality compared to those who did not (adjusted odds ratio [aOR] =0.49, 95 % CI: 0.44–0.55). Sensitivity analyses did not markedly change the estimated associations. Correction for self-selection bias reduced the effect size, but the estimate remained significant.ConclusionOur results indicate that in a context of high opportunistic screening rates, participation in breast cancer screening program substantially reduces breast cancer-specific mortality. For policy, these results should be balanced against the potential harms of screening, including overdiagnosis and overtreatment.     

Microdosimetric analysis of various mammography spectra: lineal energy distributions and ionization cluster analysis

In view of recent recommendations on the frequency and the starting age of mammography screening in healthy women, it is desirable to quantify the enhanced relative biological effectiveness (RBE) of mammography X rays compared to hard X rays. While there is little doubt that the former are more potent in inducing biological damage than the latter, the magnitude of the effect is still hotly debated in the literature. We used Monte Carlo simulations and track structure analysis in micrometer and nanometer volumes to investigate differences in distributions of lineal energy and ionization clusters for a range of mammography X-ray qualities. Dose-averaged lineal energies, (yD), in breast tissue for various mammography qualities were found to result in quality factors about 40% higher than unity. Among the various mammography qualities studied, the popular molybdenum/molybdenum target/filter combination was found to have the highest (yD) in 1-microm spheres (about 5.0 keV/microm near the entrance surface of breast tissue). In 10-nm radius spheres, the mean ionization cluster order was found to be about 35% higher in mammography X rays compared to 300 keV electrons (roughly representing 60Co or 192Ir photon radiation). In even smaller spheres (2 nm radius), no significant differences were observed for the mean ionization cluster order between mammography X rays and 300 keV electrons. We conclude that the potential of mammography X rays to induce biological damage is probably not much higher than a factor of two compared to hard X rays.     

Preventive health care, 1999 update: 3. Follow-up after breast cancer

OBJECTIVE: To make recommendations to physicians who provide follow-up care for women who have been treated for early-stage breast cancer. OPTIONS: Combination of blood tests, bone scans, liver echography and chest radiography for detection of distant disease; physical examination with or without mammography for detection of contralateral breast cancer; and physical examination with or without mammography for detection of ipsilateral recurrent disease after breast-conserving therapy. OUTCOMES: Survival, disease recurrence and quality-of-life measures for distant disease, local recurrence of disease and disease in the contralateral breast. EVIDENCE: A MEDLINE search for relevant articles published between January 1966 and January 1998 with the MeSH terms "breast neoplasms" and "neoplasm recurrence" (local and distant) with limits to "human" was done. A subsequent MEDLINE search using the MeSH terms "breast neoplasms," "neoplasm recurrence," "local/diagnosis" and "mammography" was done to address issues of mammography. The literature search was reviewed by a medical librarian and 2 breast cancer specialists to ensure completeness. BENEFITS, HARMS AND COSTS: Breast cancer is the most common cancer in Canadian women and is the second leading cause of death after lung cancer. Even with early-stage breast cancer, recurrence after treatment for primary breast cancer is frequent. Traditionally, follow-up has been felt to facilitate early detection and improve survival. Randomized controlled trials (RCTs) have shown that routine screening (blood tests and diagnostic imaging) for distant disease does not alter survival or quality of life over routine physical examination. In an underpowered secondary analysis of RCT data, the detection of contralateral breast cancer did not affect survival. However, there have been no RCTs examining the role of mammography and physical examination and their effect on survival in the detection of contralateral breast cancer. The sensitivity and specificity of mammography after local excision and radiotherapy is unknown. There have been no RCTs examining the role of mammography or physical examination, or both, and their effect on survival in the detection of ipsilateral breast recurrence. VALUES: The strength of evidence was evaluated using the methods of the Canadian Task Force on Preventive Health Care. A high value was placed on interventions that changed survival. When evidence was available, high value was also placed on interventions that affected quality of life. RECOMMENDATIONS: There is good evidence not to include blood work and diagnostic imaging as part of screening for distant disease (grade E recommendation). There is no evidence to suggest that mammography decreases mortality by detecting ipsilateral disease in the conservatively treated breast; however, there is indirect evidence that it may be beneficial (grade C recommendation). There is no direct evidence to suggest that physical examination or mammography, or both, should be used to detect contralateral breast cancer; however, there is indirect evidence that it may be beneficial (grade C recommendation). VALIDATION: The findings of this analysis were reviewed through an iterative process by the members of the Canadian Task Force on Preventive Health Care.     

Effectiveness of the public health policy for breast cancer screening in Finland: population based cohort study.

OBJECTIVE: To evaluate the effectiveness of screening for breast cancer as a public health policy. DESIGN: Follow up in 1987-92 of Finnish women invited to join the screening programme in 1987-9 and of the control women (balanced by age and matched by municipality of residence), who were not invited to the service screening. SETTING: Finland. SUBJECTS: Of the Finnish women born in 1927-39, 89893 women invited for screening and 68862 controls were followed; 1584 breast cancers were diagnosed. MAIN OUTCOME MEASURES: Rate ratio of deaths from breast cancer among the women invited for screening to deaths among those not invited. RESULTS: There were 385 deaths from breast cancer, of which 127 were among the 1584 incident cases in 1987-92. The rate ratio of death was 0.76 (95% confidence interval 0.53 to 1.09). The effect was larger and significant (0.56; 0.33 to 0.95) among women aged under 56 years at entry. 20 cancers were prevented (one death prevented per 10000 screens). CONCLUSIONS: A breast screening programme can achieve a similar effect on mortality as achieved by the trials for breast cancer screening. However, it may be difficult to justify a screening programme as a public health policy on the basis of the mortality reduction only. Whether to run a screening programme as a public health policy also depends on its effects on the quality of life of the target population and what the resources would be used for if screening was not done. Given all the different dimensions in the effect, mammography based breast screening is probably justifiable as a public health policy.     

Coverage rate of opportunistic and organised breast cancer screening in France: Department-level estimation

ObjectiveIn France, the national breast cancer screening programme (NBCSP), targeting women aged 50–74 years was rolled out nationwide in 2004. It aims at reducing breast cancer mortality. In addition to the NBCSP, the use of opportunistic screening is permitted in France. The objective of this study is to estimate both opportunistic use and overall coverage rates of breast cancer screening, among women 40–84 years of age, in France.MethodsThe French medico-administrative health data system (SNDS) was used to identify women performing an opportunistic or organised mammography screening in France in 2016–2017.ResultsThe two-yearly opportunistic mammography screening is 18 % among women aged 40–84; it is 11 % among women aged 50–74, i.e., the target age range for organised screening, 36 % among women aged 40–49 and 13 % among women aged 75–84. The overall two-yearly screening coverage is 48 % for all women aged 40–84; it is 60 % among women aged 50–74, 36 % among women 40–49 and 16 % for those aged 75–84. Geographical variations in screening are lessened when the two screening strategies are considered, as they balance each other.ConclusionAlthough coverage in the NBCSP is around 50 % in France, more than one third of the women make use of opportunistic screening within and outside the target age range. Organized screening appears to improve equity of access to mammography screening service. The lack of data on opportunistic screening practices hinders the evaluation of French screening practices as a whole.     

Mammography screening and breast self-examination among minority women in public housing projects: the impact of physician recommendation.

This exploratory study examined the impact of physician recommendations and other factors on mammography screening and breast-self examination (BSE) among African American and Hispanic women in public housing communities. We surveyed a randomly selected sample of low-income households from three low-income communities (n = 291), which included both African Americans and Hispanic women. Data for this paper are reported only on women who were 40 years and older head of the households (n = 120 women, including 74 Hispanics and 46 African Americans), since they meet the age criterion for mammography screening. Our analyses indicated that only 46% of women obtained mammography in the previous 12 months, with no significant differences between the Hispanic and African American women in mammography rates. Physicians' recommendations were among the most significant and substantial predictors of obtaining a mammogram or performing BSE. Further, odds were also higher for those who had insurance coverage. In addition, our data also indicated that almost one out of four women, aged 40 and older participants in this study, claimed that their health care providers never told them they needed a mammogram or never told them that they should perform BSE, with no significant differences between Hispanic and African Americans. Our analyses points to an urgent need for intervention to inform and motivate the service providers in underserved communities to motivate breast cancer screening (BCS) among minority women. Additionally, our examination points to the need for urgent interventions targeting minority women, particularly women with no medical insurance for breast cancer screening.     

Cost-Effectiveness Analysis of Breast Cancer Control Interventions in Peru

Objectives

In Peru, a country with constrained health resources, breast cancer control is characterized by late stage treatment and poor survival. To support breast cancer control in Peru, this study aims to determine the cost-effectiveness of different breast cancer control interventions relevant for the Peruvian context.

Methods

We performed a cost-effectiveness analysis (CEA) according to WHO-CHOICE guidelines, from a healthcare perspective. Different screening, early detection, palliative, and treatment interventions were evaluated using mathematical modeling. Effectiveness estimates were based on observational studies, modeling, and on information from Instituto Nacional de Enfermedades Neoplásicas (INEN). Resource utilizations and unit costs were based on estimates from INEN and observational studies. Cost-effectiveness estimates are in 2012 United States dollars (US$) per disability adjusted life year (DALY) averted.

Results

The current breast cancer program in Peru ($8,426 per DALY averted) could be improved through implementing triennial or biennial screening strategies. These strategies seem the most cost-effective in Peru, particularly when mobile mammography is applied (from $4,125 per DALY averted), or when both CBE screening and mammography screening are combined (from $4,239 per DALY averted). Triennially, these interventions costs between $63 million and $72 million per year. Late stage treatment, trastuzumab therapy and annual screening strategies are the least cost-effective.

Conclusions

Our analysis suggests that breast cancer control in Peru should be oriented towards early detection through combining fixed and mobile mammography screening (age 45-69) triennially. However, a phased introduction of triennial CBE screening (age 40-69) with upfront FNA in non-urban settings, and both CBE (age 40-49) and fixed mammography screening (age 50-69) in urban settings, seems a more feasible option and is also cost-effective. The implementation of this intervention is only meaningful if awareness raising, diagnostic, referral, treatment and basic palliative services are simultaneously improved, and if financial and organizational barriers to these services are reduced.     

Testing the Independence of Two Diagnostic Tests

Consider two diagnostic procedures having binary outcomes. If one of the tests results in a positive finding, a more definitive diagnostic procedure will be administered to establish the presence or absence of a disease. The use of both tests will improve the overall screening sensitivity when the two tests are independent, compared with employing two tests that are positively correlated. We estimate the correlation coefficient of the two tests and derive statistical methods for testing the independence of the two diagnostic procedures conditional on disease status. The statistical tests are used to investigate the independence of mammography and clinical breast exams aimed at establishing the benefit of early detection of breast cancer. The data used in the analysis are obtained from periodic screening examinations of three randomized clinical trials of breast cancer screening. Analysis of each of these trials confirms the independence of the clinical breast and mammography examinations. Based on these three large clinical trials, we conclude that a clinical breast exam considerably increases the overall sensitivity relative to screening with mammography alone and should be routinely included in early breast cancer detection programs.     

Incidence of breast cancer in Norway and Sweden during introduction of nationwide screening: prospective cohort study

Objective To determine whether any increase in the incidence of breast cancer in women detected by mammography is compensated for by a drop in the incidence after age 69, years when women are no longer invited for screening.Design Population based cohort study of incidence of breast cancer during the introduction of nationwide screening programmes.Setting Norway and Sweden.Participants All women aged above 30 years (1.4 and 2.9 million, respectively, in 2000).Main outcome measures Changes in age specific incidence rates of invasive breast cancer associated with the introduction of the screening programmes.Results As a result of screening the recorded incidence of breast cancer in women aged 50-69 years increased by 54% in Norway and 45% in Sweden. There was no corresponding decline in incidence after the age of 69 years.Conclusions Without screening one third of all invasive breast cancers in the age group 50-69 years would not have been detected in the patients'' lifetime. This level of overdiagnosis is larger than previously reported.     

Is mammography indicated for women with defective BRCA genes? Implications of recent scientific advances for the diagnosis, treatment, and prevention of hereditary breast cancer

About 5% of breast cancer patients have inherited their disease because of a mutation in genes encoding either the BRCA-1 or BRCA-2 proteins. Inheriting one of these mutations confers a 50% to 87% risk of breast cancer. Many physicians faced with such a patient would, at a minimum, suggest increased and earlier screening for breast cancer by routine mammography.[1] Normally, regular mammographic screening combined with appropriate and prompt treatment can reduce mortality from breast cancer by 30% in women aged 50-59 years and by about 14%-18% in women aged 40-49. There are no controlled clinical trials for screening young women who have multiple first-degree relatives developing breast cancer before age 45, or those known to carry BRCA-1 or BRCA-2 mutations. In fact, recent advances point out that BRCA-1 and BRCA-2 gene products are needed to repair radiation damage to DNA.[4,5] Based on this finding, I propose that women with defective BRCA genes are likely to have an inordinate sensitivity to radiation, and this raises a question about the advisability of routinely screening these women by frequent mammography.     

How should we interpret noncompliance with screening mammography?

Primary care practitioners have an important role to play in recommending breast cancer screening to patients in the target age group. In this issue of CMAJ (see pages 1335 to 1343) Dr. Marie-Dominique Beaulieu and associates report the results of a program designed to maximize utilization of screening mammography. Only two thirds of eligible women for whom screening mammography was prescribed obtained a mammogram within the 2-month study period. However, when taken in context, this compliance rate is fairly encouraging. There are many possible reasons for noncompliance such as a need for more information or for repeated suggestions. Family physicians should not become disheartened in their efforts to increase the use of screening procedures and may find that collaboration with others in giving consistent messages will help to maximize screening rates within their patient population.     

Interval cancers as related to frequency of recall to assessment in the South Australian population-based breast screening program: An exploratory study

Australian accreditation standards specify upper limits for percentages of women recalled for further assessment following screening mammography. These limits have been unchanged since national screening commenced circa 1990, although screening target ages have changed, and technology from analogue to digital mammography. This study compared 2804 women with interval cancers diagnosed since national screening began (cases) with 14,020 cancer-free controls (5 controls per case), randomly selected after matching by age, round, screen type and calendar year of screening episode, to determine the odds of interval cancer by differences in clinic recall to assessment percentages. Within low numbers of recalls that were within accepted accreditation ranges, results did not indicate more frequent recalls to assessment to be associated with fewer interval cancers in the analogue era. However, more frequent recalls were associated with reduced interval cancers for digital screens. These results are not conclusive, requiring confirmation in other screening environments, especially those with larger numbers of digital screens. If confirmed, frequency of recalls to assessment may need adjustment to get the best trade-offs in the digital era between reduced odds of interval cancers from more recalls and increases in financial and non-financial costs, including increased potential for overdiagnosis.     

Neglected aspects of false positive findings of mammography in breast cancer screening: analysis of false positive cases from the Stockholm trial.

OBJECTIVES: To examine the implications of false positive results of mammography in terms of the time lag from screening and complete mammography to the point when women with false positive results are declared free of cancer; the extra examinations, biopsies, and check ups required; and the cost of these extra procedures. DESIGN: Review of women with false positive results from the Stockholm mammography screening trial. SETTING: Department of Oncology, South Hospital, Stockholm. SUBJECTS: 352 and 150 women with false positive results of mammography from the first and second screening rounds of the Stockholm trial. MAIN OUTCOME MEASURES: Extra examinations and investigations required and the cost of these procedures. RESULTS: The 352 women from the first screening round made 1112 visits to the physician and had 397 fine needle aspiration biopsies, 187 mammograms, and 90 surgical biopsies before being declared free of cancer. After six months 64% of the women (219/342) were declared cancer free. The 150 women in the second round made 427 visits to the physician and had 145 fine needle aspiration biopsies, 70 mammograms, and 28 surgical biopsies, and after six months 73% (107/147) were declared cancer free. The follow up costs of the false positive screening results were Kr2.54m (250,000 pounds) in the first round and Kr0.85m (84,000 pounds) in the second round. Women under 50 accounted for about 41% of these costs. CONCLUSIONS: The examinations and investigation carried out after false positive mammography --especially in women under 50--and the cost of these procedures are a neglected but substantial problem.     

Age as a factor in breast cancer knowledge,attitudes and screening behaviour.

OBJECTIVE: To determine whether there are age-related differences in knowledge, attitudes and behaviour with respect to breast cancer and whether the differences reflect the age-specific Canadian recommendations on breast cancer screening. DESIGN: Telephone survey. SETTING: Two cities and five towns and their surrounding areas in Alberta. PARTICIPANTS: The age-specific, randomly selected sample comprised 1284 women aged 40 to 75 years who did not have breast cancer. Of the 1741 eligible women who were contacted, 1350 (78%) agreed to participate; 66 were excluded because of age ineligibility or a history of breast cancer. MAIN OUTCOME MEASURE: Frequency of knowledge, attitudes and behaviour with respect to breast cancer, by age group. RESULTS: Knowledge of breast cancer risk factors was generally low and decreased with age. Few women were aware of the Canadian recommendations on breast self-examination, physical examination of the breasts by a health care practitioner and mammographic screening. Older women believed they were less susceptible to breast cancer than younger women and were less likely to have positive attitudes toward screening. Self-examination was performed 9 to 15 times per year by 424 women (33%), and 810 (63%) had been examined by a health care professional in the past year. Although 664 (52%) had undergone mammography, the proportion decreased with age after age 59. The main barriers to mammography were lack of physician referral and the woman''s belief that the procedure is unnecessary if she is healthy. CONCLUSIONS: Education is needed to increase breast cancer knowledge, promote the Canadian recommendations for early detection of breast cancer and decrease negative beliefs about the disease. Changes in the behaviour of women and physicians are needed to increase the use of breast self-examination, clinical breast examination by a health care professional and mammographic screening. Reaching women in the upper range (60 to 69 years) of the target group for mammographic screening should be a focus in promoting early detection of breast cancer.     

Factors associated with annual-interval mammography for women in their 40s

Background: Evidence is mounting that annual mammography for women in their 40s may be the optimal schedule to reduce morbidity and mortality from breast cancer. Few studies have assessed predictors of repeat mammography on an annual interval among these women. Methods: We assessed mammography screening status among 596 insured Black and Non-Hispanic white women ages 43–49. Adherence was defined as having a second mammogram 10–14 months after a previous mammogram. We examined socio-demographic, medical and healthcare-related variables on receipt of annual-interval repeat mammograms. We also assessed barriers associated with screening. Results: 44.8% of the sample were adherent to annual-interval mammography. A history of self-reported abnormal mammograms, family history of breast cancer and never having smoked were associated with adherence. Saying they had not received mammography reminders and reporting barriers to mammography were associated with non-adherence. Four barrier categories were associated with women's non-adherence: lack of knowledge/not thinking mammograms are needed, cost, being too busy, and forgetting to make/keep appointments. Conclusions: Barriers we identified are similar to those found in other studies. Health professionals may need to take extra care in discussing mammography screening risk and benefits due to ambiguity about screening guidelines for women in their 40s, especially for women without family histories of breast cancer or histories of abnormal mammograms. Reminders are important in promoting mammography and should be coupled with other strategies to help women maintain adherence to regular mammography.     

Incidence of breast cancer and estimates of overdiagnosis after the initiation of a population-based mammography screening program

Background:

There has been growing interest in the overdiagnosis of breast cancer as a result of mammography screening. We report incidence rates in British Columbia before and after the initiation of population screening and provide estimates of overdiagnosis.

Methods:

We obtained the numbers of breast cancer diagnoses from the BC Cancer Registry and screening histories from the Screening Mammography Program of BC for women aged 30–89 years between 1970 and 2009. We calculated age-specific rates of invasive breast cancer and ductal carcinoma in situ. We compared these rates by age, calendar period and screening participation. We obtained 2 estimates of overdiagnosis from cumulative cancer rates among women between the ages of 40 and 89 years: the first estimate compared participants with nonparticipants; the second estimate compared observed and predicted population rates.

Results:

We calculated participation-based estimates of overdiagnosis to be 5.4% for invasive disease alone and 17.3% when ductal carcinoma in situ was included. The corresponding population-based estimates were −0.7% and 6.7%. Participants had higher rates of invasive cancer and ductal carcinoma in situ than nonparticipants but lower rates after screening stopped. Population incidence rates for invasive cancer increased after 1980; by 2009, they had returned to levels similar to those of the 1970s among women under 60 years of age but remained elevated among women 60–79 years old. Rates of ductal carcinoma in situ increased in all age groups.

Interpretation:

The extent of overdiagnosis of invasive cancer in our study population was modest and primarily occurred among women over the age of 60 years. However, overdiagnosis of ductal carcinoma in situ was elevated for all age groups. The estimation of overdiagnosis from observational data is complex and subject to many influences. The use of mammography screening in older women has an increased risk of overdiagnosis, which should be considered in screening decisions.There is growing interest in the overdiagnosis of breast cancer resulting from mammography screening.^1,2 It has been suggested that incidence rates after the introduction of mammography screening are higher than would be expected from the early detection of clinically significant disease alone. The clinical importance of ductal carcinoma in situ has long been unclear, and recent attention has also focused on the potential overdiagnosis of invasive cancer.^1,3,4 Furthermore, more frequent screening, wider age ranges and higher false-positive rates in much of North America may result in increased overdiagnosis⁵ in comparison with Europe, the source of most reports.The Screening Mammography Program of BC provides bilateral 2-view mammography screening to female residents of British Columbia. The program began in 1988 at a single location and progressively expanded by adding centres in larger communities and extending mobile services; by 2000, geographic coverage was effectively 100%. Women aged 40–79 years are eligible to self-refer. Since 1997, women aged 40–49 years are reminded to return annually, and those over 50 years of age are reminded to return biennially. Women outside of this age-range can undergo screening with a physician’s referral. Rates of abnormal results on screening mammography in British Columbia are comparable to the community rates seen in the United States.⁶Our primary objective for this study was to estimate the extent of overdiagnosis of breast cancer due to screening. To do this, we examined cancer rates in the following subpopulations: all women 1970–1979, and women in 2005–2009 classified by active and nonactive participation in screening. From 1970 to 1979, screening was infrequent and no organized program existed. In the period 2005–2009, screening was well established and the use of hormone replacement therapy for menopause had declined.⁷ Our secondary objective was to determine the changes in population incidence of breast cancer, both invasive and ductal carcinoma in situ, following the implementation of a population-based screening program. Thus, we report an analysis of population age-specific incidence rates in British Columbia over a 40-year period (1970–2009).     

Accuracy of Screening Methods for the Diagnosis of Breast Disease

Clinical examination, thermography, and 70-mm. mammography were performed in 891 patients—414 presented to hospital with symptoms of breast disease and 477 were asymptomatic. Comparison of the diagnostic accuracy of these methods showed that neither thermography nor 70-mm. mammography has a useful place as an isolated screening procedure for breast cancer. In fact, we consider such a policy dangerous.     

Mammography screening in the county of Fyn. November 1993-December 1999

This report covers the outcome of the first three invitation rounds of the organised mammography screening programme in the county of Fyn. The programme started in November 1993, and the third invitation round ended on 31 December 1999. The screening takes place either at a special clinic located at University Hospital Odense or in a mobile unit. Women living in and around the city of Odense are examined at the clinic (about 55%), while the rest are examined in the mobile unit. Two-view mammography is used at the first screening. Women with dense breast tissue will continue to have two-view mammography (about 60%), whereas the rest will have singleview mammography at the subsequent screens. All screening images are exposed at the mammography-screening clinic and evaluated with double reading in the clinic. The programme targets women aged 50-69, except those undergoing treatment for breast cancer or going for regular check-ups following breast cancer. Based on the updated population register, the IT-Centre of the county of Fyn issues the invitations. Invited are all women aged 50-69 and living in the county of Fyn when their general practitioners' patients are invited. During the first 3 invitation rounds, 136,079 screening tests were made. Of these, 129,375 tests were made in the women aged 50-69 targeted by the programme. In addition, 6682 screening tests were made in women aged 70 and above, and 22 screening tests were made in women below the age of 50. As a consequence of the mammography screening 2657 assessments were made, 1145 women had surgery, 782 women were diagnosed with invasive breast cancer, and 109 women were diagnosed with ductal carcinoma in situ. A participation rate for the first invitation round was calculated immediately after the end of the round based on the number of participants divided by the number of women invited. This percentage was 88%. Invitation data are, however, not stored. It is therefore not possible now to calculate the participation rates in previous invitation rounds based on the same method. We have therefore chosen to calculate the participation rate as the coverage, i.e. the number of participants divided by the average number of women in the county of Fyn during a given invitation round. Calculated in this way, 84% participated in the first round, 84% in the second round, and 82% in the third round. It should be remembered that these figures do not take into account that some women are not invited because they 1) were undergoing current treatment for breast cancer or going for regular check-ups following breast cancer, or 2) did not participate in the previous round (and never actively informed the programme that they wanted an invitation to the next invitation round), relevant only for the second and third invitation round. For the second and third invitation rounds, the programme only invited women who participated in the previous invitation round, asked the clinic for an invitation, or entered the target population since the last invitation round. Therefore the participation rate in the second invitation round among actually invited women will be close to 94%, as 94% of those participating in the first round came for the second round. For the third invitation round, the participation rate among actually invited women will be close to 96%, as 96% of those participating in the first and second rounds came for the third round. One per cent of the participants in the first invitation round were diagnosed with invasive breast cancer or ductal carcinoma in situ. The detection rate was 0.5% in both the second and third invitation rounds. Ductal carcinoma in situ cases constituted 14% of the detected cases in the first and second rounds, and 10% in the third round. The percentage of invasive breast cancer 10 mm of less was 38%, 31%, and 32%, respectively, and 68%, 74%, and 73%, respectively, were node-negative. The screening programme of the county of Fyn fulfilled all the quality assessment parameters specified by the European guidelines on breast cancer screening, except two. The proportionate interval cancer rate was higher than specified in the guidelines, probably mainly due to the fact that the Fyn programme operates without early recalls. The proportion of stage II+ cancers was higher than specified in the guidelines, which seems, however, to be due to inconsistency between some of the performance indicators in the European guidelines. This analysis of the outcome from the first three invitation rounds of the mammography screening programme in the county of Fyn thus showed that it is a programme of high quality with a favourable profile of the prognostic indicators. The screening programme is hopefully well on its way to reducing breast cancer mortality in the county of Fyn.     

Application of Breast Ultrasound in a Mammography-Based Chinese Breast Screening Study

We evaluated the clinical significance of the combined use of mammography + ultrasound as a new breast screening strategy. The inclusion criteria were: (1) females aged >40yrs; (2) breast cancer diagnosis by the breast image screening personnel at FUSCC; (3) screening by both ultrasound and mammography; (4) mammographic/sonographic images analyzed independently by different radiologists; and (5) follow-up for at least 1 year. Fifty-four women were enrolled. The analysis included diagnostic sensitivity of mammography, ultrasound, and mammography + ultrasound. The sensitivities of mammography and mammography + ultrasound were compared overall as well as among different age groups/breast densities. The screening sensitivity of mammography, ultrasound, and mammography + ultrasound was 79.6, 57.4, and 92.6 %, respectively. The difference between mammography and mammography + ultrasound was significant (P < 0.05). The benefit of including ultrasound with mammography as a new breast image screening strategy was found statistically significant in patients with dense breast on mammogram while it was non-significant in younger (<50 years) women. We, therefore, concluded that mammography + ultrasound increased the diagnostic sensitivity of breast screening; hence it was more desirable for women with dense breast on mammography.     

Model of outcomes of screening mammography: information to support informed choices

Objective To provide easy to use estimates of the benefits and harms of biennial screening mammography for women aged 40, 50, 60, and 70 years.Design Markov process model, with data from BreastScreen Australia, the Australian Institute of Health and Welfare, and the Australian Bureau of Statistics.Main outcome measure Age specific outcomes expressed per 1000 women over 10 years.Results For every 1000 women screened over 10 years, 167-251 (depending on age) receive an abnormal result; 56-64 of these women undergo at least one biopsy, 9-26 have an invasive cancer detected by screening, and 3-6 have ductal carcinoma in situ (DCIS) detected by screening. More breast cancers (both invasive and DCIS) are diagnosed among screened than unscreened women. For example, among 1000 women aged 50 who have five biennial screens, 33 breast cancers are diagnosed: 28 invasive cancers (18 detected at screening and 10 interval cancers) and five DCIS (all detected at screening). By comparison, among 1000 women aged 50 who decline screening, 20 cancers are diagnosed over 10 years. There are about 0.5, 2, 3, and 2 fewer deaths from breast cancer over 10 years per 1000 women aged 40, 50, 60, and 70, respectively, who choose to be screened compared with women who decline screening at times determined by relevant policy.Conclusion Benefits and harms of screening mammography are relatively finely balanced. Quantitative estimates such as these can be used to support individual informed choices about screening.