Screening and self examination for breast cancer.

Breast cancer is the major form of cancer in women, with nearly 30,000 new cases and over 15,000 deaths in the United Kingdom each year. Breast screening by mammography has been shown in randomised trials to reduce mortality from breast cancer in women aged 50 and over. An NHS breast screening programme has been in operation in the United Kingdom since 1988. Its aim is to reduce mortality from breast cancer by 25% in the population of women invited to be screened. The uptake of mammography among the eligible population may be the single most important determinant if the programme is to be effective. Primary care teams have an important part to play in encouraging women to attend for screening and in providing information, advice, and reassurance at all stages of the screening process. To date, routine breast self examination has not been shown to be an effective method of screening for breast cancer and should not therefore be promoted as a primary screening procedure. There is, however, a case to be made for women to become more "breast aware."     

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.     

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.     

Cancer incidence and mortality in people aged less than 75 years: Changes in Australia over the period 1987–2007

BackgroundAustralia has one of the highest rates of cancer incidence worldwide and, despite improving survival, cancer continues to be a major public health problem. Our aim was to provide simple summary measures of changes in cancer mortality and incidence in Australia so that progress and areas for improvement in cancer control can be identified.MethodsWe used national data on cancer deaths and newly registered cancer cases and compared expected and observed numbers of deaths and cases diagnosed in 2007. The expected numbers were obtained by applying 1987 age–sex specific rates (average of 1986–1988) directly to the 2007 population. The observed numbers of deaths and incident cases were calculated for 2007 (average of 2006–2008). We limited the analyses to people aged less than 75 years.ResultsThere was a 28% fall in cancer mortality (7827 fewer deaths in 2007 vs. 1987) and a 21% increase in new cancer diagnoses (13,012 more diagnosed cases in 2007). The greatest reductions in deaths were for cancers of the lung in males (?2259), bowel (?1797), breast (?773) and stomach (?577). Other notable falls were for cancers of the prostate (?295), cervix (?242) and non-Hodgkin lymphoma (?240). Only small or no changes occurred in mortality for cancers of the lung (female only), pancreas, brain and related, oesophagus and thyroid, with an increase in liver cancer (267). Cancer types that showed the greatest increase in incident cases were cancers of the prostate (10,245), breast (2736), other cancers (1353), melanoma (1138) and thyroid (1107), while falls were seen for cancers of the lung (?1705), bladder (?1110) and unknown primary (?904).ConclusionsThe reduction in mortality indicates that prevention strategies, improvements in cancer treatment, and screening programmes have made significant contributions to cancer control in Australia since 1987. The rise in incidence is partly due to diagnoses being brought forward by technological improvements and increased coverage of screening and early diagnostic testing.     

Screening for breast cancer.

The feasibility of mass population screening for breast cancer by clinical examination and x-ray mammography was studied. The results indicate that such a programme could be conducted effectively by non-medical staff and be safe from the dangers of irradiation. The response rate of women invited for screening suggests that such a service is acceptable to the general public. The additional work load produced by screening would not overburden the existing surgical services.     

Mammographic screening and mortality from breast cancer: the Malm? mammographic screening trial.

STUDY OBJECTIVE--To determine whether mortality from breast cancer could be reduced by repeated mammographic screening. DESIGN--Birth year cohorts of city population separately randomised into study and control groups. SETTING--Screening clinic outside main hospital. PATIENTS--Women aged over 45; 21,088 invited for screening and 21,195 in control group. INTERVENTIONS--Women in the study group were invited to attend for mammographic screening at intervals of 18-24 months. Five rounds of screening were completed. Breast cancer was treated according to stage at diagnosis. END POINT--Mortality from breast cancer. MEASUREMENTS AND MAIN RESULTS--All women were followed up and classed at end point as alive without breast cancer, alive with breast cancer, dead from breast cancer, or dead from other causes. Cause of death was taken from national mortality registry and for patients with breast cancer was validated independently. Mean follow up was 8.8 years. Altogether 588 cases of breast cancer were diagnosed in the study group and 447 in the control group; 99 v 94 women died of all causes and 63 v 66 women died of breast cancer (no significant difference; relative risk 0.96 (95% confidence interval 0.68 to 1.35)). In the study group 29% more women aged less than 55 died of breast cancer (28 v 22; relative risk 1.29 (0.74 to 2.25)). More women in the study group died from breast cancer in the first seven years; after that the trend reversed, especially in women aged greater than or equal to 55 at entry. Overall, women in the study group aged greater than or equal to 55 had a 20% reduction in mortality from breast cancer (35 v 44; relative risk 0.79 (0.51 to 1.24)). OTHER FINDINGS--In the study group 100 (17%) cancers appeared in intervals between screenings and 107 (18%) in non-attenders; 51 of these women died from breast cancer. Cancers classed as stages II-IV comprised 33% (190/579) of cancers in the study group and 52% (231/443) in the control group. CONCLUSIONS--Invitation to mammographic screening may lead to reduced mortality from breast cancer, at least in women aged 55 or over.     

Response by women aged 65-79 to invitation for screening for breast cancer by mammography: a pilot study.

OBJECTIVE--To determine whether there is sufficient benefit to be gained by offering screening for breast cancer with mammography to women aged 65-79, who are not normally invited for screening. DESIGN--Pilot study of women eligible for screening but not for personal invitation. The results of this study were compared with the results of routinely screened younger women (aged 50-64) from the same general practice. SETTING--One group general practice in south Manchester. PATIENTS--The 631 women aged 65-79 on the practice list. A total of 42 (7%) were excluded by the general practitioner, and 22 (4%) invitation letters were returned by the post office. MAIN OUTCOME MEASURES--Response rates to invitation for screening assessed by three indices: crude population coverage ratio, crude invited population coverage ratio, and corrected invited population coverage ratio. RESULTS--344 Patients aged 65-79 (61% of those invited, excluding those who could not be traced) were screened compared with 77% of women aged 50-64. The three response indices were higher for younger women than older: crude population coverage ratio = 66.5%, crude invited population coverage ratio = 69.3%, corrected invited population coverage ratio = 76.8% for women aged 50-64, compared with 54.5%, 58.4%, and 60.7% respectively for women aged 65-79. All four biopsies done in the older women gave positive results, giving a cancer detection rate of 11.6/1000 compared with 4.1/1000 among younger women. CONCLUSIONS--These results show that there is a potential for high attendance at routine screening by older women if they are invited in the same way as younger women. If these results are found elsewhere the costs and benefits of screening older women should be reassessed.     

Attending the breast screening programme after breast cancer treatment: A population-based study

IntroductionIn the Netherlands, breast cancer patients are treated and followed at least 5 years after diagnosis. Furthermore, all women aged 50–74 are invited biennially for mammography by the nationwide screening programme. The relation between the outpatient follow-up (follow-up visits in the outpatient clinic for 5 years after treatment) and the screening programme is not well established and attending the screening programme as well as outpatient follow-up is considered undesirable. This study evaluates potential factors influencing women to attend the screening programme during their outpatient follow-up (overlap) and the (re-)attendance to the screening programme after 5 years of outpatient follow-up.MethodsData of breast cancer patients aged 50–74 years, treated for primary breast cancer between 1996 and 2007 were selected from the Netherlands Cancer Registry and linked to the National Breast Cancer Screening Programme in the Northern region. Cox regression analyses were used to study women (re-)attending the screening programme over time, possible overlap with the outpatient follow-up and factors influencing this.ResultsIn total 11 227 breast cancer patients were included, of whom 19% attended the screening programme after breast cancer treatment, 4.4% within 5 years and 15.4% after more than 5 years. Factors that independently influenced attendance within 5 years as well as more than 5 years after treatment were: interval tumours (HR 0.77; 95%CI 0.61–0.97 and HR 0.69; 95%CI 0.53–0.88, ref: screen-detected tumours), receiving adjuvant radiotherapy (HR 0.65; 95%CI 0.47–0.90 and HR 0.66; 95%CI 0.47–0.93; ref: none) and diagnosis of in situ tumours (HR 1.67; 95%CI 1.25–2.23 and HR 1.39; 95%CI 1.05–1.85; ref: stage I tumours). Non-screen related tumours (HR 0.41; 95%CI 0.29–0.58) and recent diagnosis (HR 0.89 per year; 95%CI 0.86–0.92) were only associated with attendance within 5 years after treatment.ConclusionThe interrelation between outpatient follow-up and screening should be improved to avoid overlap and low attendance to the screening programme after outpatient follow-up. Breast cancer patients should be informed that attending the screening programme during the outpatient follow-up is not necessary.     

Is the three year breast screening interval too long? Occurrence of interval cancers in NHS breast screening programme's north western region.

OBJECTIVE--To report the detection rate of interval cancers in women screened by the NHS breast screening programme. DESIGN--Detection of interval cancers by computer linkage of records held by the screening centres in the North Western Regional Health Authority with breast cancer registrations at the regional cancer registry. SETTING--North Western Regional Health Authority. SUBJECTS--137,421 women screened between 1 March 1988 and 31 March 1992 who had a negative screening result. RESULTS--297 invasive interval cancers were detected. The rate of detection of interval cancers expressed as a proportion of the underlying incidence was 31% in the first 12 months after screening, 52% between 12 and 24 months, and 82% between 24 and 36 months. CONCLUSION--The incidence of interval cancers in the third year after breast screening approaches that which would have been expected in the absence of screening and suggests that the three year interval between screens is too long.     

National Health Service breast screening programme results for 1991-2.

OBJECTIVES--To report the results of the NHS breast screening programme for the year March 1991 to April 1992. DESIGN--A report of statistics was derived from Körner (K62) returns and from the radiology quality assurance programme. MAIN OUTCOME MEASURES--Detection rates for breast cancer and small (< or = 10 mm diameter) invasive cancer, benign biopsy rates, and recall and acceptance rates. RESULTS--The acceptance rate for screening across the United Kingdom was 71.3%. The referral rate for further investigation was 6.2% (regional 4.3-9.0%). The breast cancer detection rate was 6.2 cancers per 1000 women screened (5.1-9.0) and the detection rate of invasive cancers < or = 10 mm was 1.4/1000 (1.0-2.3). 72% of screening programmes reached the target 70% acceptance rate, and 95% of programmes achieved a recall rate of less than 10%. 75% of programmes had a cancer detection rate of more than 5/1000, but only 32% had a detection rate for invasive cancers < or = 10 mm of more than 1.5/1000. CONCLUSIONS--Overall, the results of the screening programme for the year 1991-2 can be regarded as extremely satisfactory, given the size and complexity of the operation.     

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.     

California's male suicide rate at record high.

Breast cancer is the most commonly occurring cancer in women and, until recently surpassed by lung cancer, was the leading cause of cancer-related death in women. It is the leading cause of death in women aged 39 to 44 years. The American Cancer Society has estimated that there will be 135,000 new cases of breast cancer and 42,300 breast cancer-related deaths in 1988. It is now predicted that breast cancer will develop in one out of every ten women in the United States. Given the clinical and public health significance of breast cancer, annual screening with mammography and clinical breast examination is recommended for women aged 50 and older to reduce breast cancer mortality.     

Socio-Economic and Health Access Determinants of Breast and Cervical Cancer Screening in Low-Income Countries: Analysis of the World Health Survey

Background

Breast and Cervical cancer are the two most common cancers among women in developing countries. Regular screening is the most effective way of ensuring that these cancers are detected at early stages; however few studies have assessed factors that predict cancer screening in developing countries.

Purpose

To assess the influence of household socio-economic status (SES), healthcare access and country level characteristics on breast and cervical cancer screening among women in developing countries.

Methods

Women ages 18–69 years (cervical cancer screening) and 40–69 years (breast cancer screening) from 15 developing countries who participated in the 2003 World Health Survey provided data for this study. Household SES and healthcare access was assessed based on self-reported survey responses. SAS survey procedures (SAS, Version 9.2) were used to assess determinants of breast and cervical cancer screening in separate models.

Results

4.1% of women ages 18–69 years had received cervical cancer screening in the past three years, while only 2.2% of women ages 40–69 years had received breast cancer screening in the past 5 years in developing countries. Cancer screening rates varied by country; cervical cancer screening ranged from 1.1% in Bangladesh to 57.6% in Congo and breast cancer screening ranged from 0% in Mali to 26% in Congo. Significant determinants of cancer screening were household SES, rural residence, country health expenditure (as a percent of GDP) as well as healthcare access.

Discussion

A lot more needs to be done to improve screening rates for breast and cervical cancer in developing countries, such as increasing health expenditure (especially in rural areas), applying the increased funds towards the provision of more, better educated health providers as well as improved infrastructure.     

Breast Cancer Screening in Saudi Arabia: Free but Almost No Takers

Introduction

Mammography ensures early diagnosis and a better chance for treatment and recovery from breast cancer. We conducted a national survey to investigate knowledge and practices of breast cancer screening among Saudi women aged 50 years or older in order to inform the breast cancer national health programs.

Materials and Methods

The Saudi Health Interview Survey is a national multistage survey of individuals aged 15 years or older. The survey included questions on socio-demographic characteristics, tobacco consumption, diet, physical activity, health-care utilization, different health-related behaviors, and self-reported chronic conditions. Female respondents were asked about knowledge and practices of self and clinical breast exams, as well as mammography.

Results

Between April and June 2013, a total of 10,735 participants completed the survey. Among respondents, 1,135 were women aged 50 years or older and were included in this analysis. About 89% of women reported not having a clinical breast exam in the past year, and 92% reported never having a mammogram. Women living in Al Sharqia had the highest rate of mammography use. Women who were educated, those who had received a routine medical exam within the last two years, and those who were diagnosed with hypertension were more likely to have had a mammogram in the past two years.

Discussion

Our results show very low rates of breast cancer screening in the Kingdom of Saudi Arabia, a country with free health services. This calls for educational campaigns to improve breast cancer screening. Addressing the barriers for breast cancer screening is a public health imperative.     

Hospital work load produced by breast-cancer screening programme run by trained non-medical staff.

In a feasibility study of mass population screening for breast cancer by annual clinical examination and mammography the findings of non-medical staff (nurses and radiographers) were used to estimate the hospital work load generated by such a programme. Among 2490 women who attended for the first time by invitation the rate of referral for a surgical opinion based on the findings of the non-medical staff was 7.9% and the biopsy rate 2.5%. In the second and third years referral rates fell to 4.3% and 2.7% respectively and the biopsy rates to 1.1% and 1.4%. The rates of referral and biopsy among 1203 women who referred themselves for screening were higher, but many self-referred women were symptomatic; those without symptoms had rates of referral and biopsy similar to those of the invited women. Extrapolation of these findings to a population of 200,000 in a typical health district showed that the hospital work load would be high in the first year of screening with 44 outpatient referrals per week and 14 biopsies. By the third year, however, only seven referrals and four biopsies a week could be expected. The work load would be reduced by a third if screening were confined to women over the age of 50.     

Does genetic counseling have any impact on management of breast cancer risk?

Despite there being an increasing literature on the impact of cancer genetic counseling on risk perception and mental health, there is a lack of data describing impact on risk management. Genetic counseling and testing for cancer predisposition genes aims to improve the future health of those at high risk through appropriate surveillance and screening. However, management of breast cancer risk in women with a family history of this disease is an area of controversy. Counseling services may recommend specific risk management options to women, who then rely on their local screening service to make provision. This study investigated the impact of genetic counseling on management of breast cancer risk in women attending Cancer Family Clinics. A total of 293 women attending four genetic clinics were enrolled. Rates of breast self-examination, clinical breast examination, mammography, biopsy, detected cancers, and other screenings were documented. Participants' perceived benefits and barriers to mammography were assessed along with cancer worry. Results show that rates of mammography, clinical breast examination, and breast self-examination were increased following clinic attendance (p < 0.001). Women in the under 35 age-group had limited access to screening. Rates for biopsy and detected cancers were low. Women reported positive attitudes to mammography, with few reported barriers. Contrary to previous studies, there was no evidence that anxiety about breast cancer impedes uptake of health surveillance methods. Genetic counseling had a positive impact on management of breast cancer risk. Whether this translates into future health gains remains to be established.     

Reliability of recording uterine cancer in death certification in France and age-specific proportions of deaths from cervix and corpus uteri

French uterine cancer recordings in death certificates include 60% of "uterine cancer, Not Otherwise Specified (NOS)"; this hampers the estimation of mortalities from cervix and corpus uteri cancers. The aims of this work were to study the reliability of uterine cancer recordings in death certificates using a case matching with cancer registries and estimate age-specific proportions of deaths from cervix and corpus uteri cancers among all uterine cancer deaths by a statistical approach that uses incidence and survival data. Deaths from uterine cancer between 1989 and 2001 were extracted from the French National database of causes of death and case-to-case matched to women diagnosed with uterine cancer between 1989 and 1997 in 8 cancer registries. Registry data were considered as "gold-standard". Among the 1825 matched deaths, cancer registries recorded 830 cervix and 995 corpus uteri cancers. In death certificates, 5% and 40% of "true" cervix cancers were respectively coded "corpus" and "uterus, NOS" and 5% and 59% of "true" corpus cancers respectively coded "cervix" and "uterus, NOS". Miscoding cervix cancers was more frequent at advanced ages at death and in deaths at home or in small urban areas. Miscoding corpus cancers was more frequent in deaths at home or in small urban areas. From the statistical method, the estimated proportion of deaths from cervix cancer among all uterine cancer deaths was higher than 95% in women aged 30-40 years old but declined to 35% in women older than 70 years. The study clarifies the reason for poor encoding of uterus cancer mortality and refines the estimation of mortalities from cervix and corpus uteri cancers allowing future studies on the efficacy of cervical cancer screening.     

Aggressiveness of breast cancers found with and without screening.

OBJECTIVE--To examine how breast cancers found by mammographic screening differ from those found outside screening. DESIGN--Comparative cohort study. SETTING--Turku, southwestern Finland. PATIENTS--126 women aged 40-74 years with breast cancer detected during the first round of mammographic screening in 1987-90 and 125 women within the same age range with breast cancer detected outside screening during the same period. MAIN OUTCOME MEASURES--Primary tumour size, axillary nodal status, histological features, oestrogen and progesterone receptor concentrations, ploidy, and S phase fraction. RESULTS--Compared with the controls women with cancers detected by screening had a smaller primary tumour (57 (46%) screened v 11 (10%) controls had tumours less than or equal to 11 mm in diameter, p less than 0.0001), and less often had axillary nodal metastases (104 (83%) screened v 71 (57%) controls node negative, p less than 0.0001). After adjustment for the smaller size of the primary tumour compared with control cancers, those cancers detected by screening were less likely to have axillary nodal metastases (odds ratio 0.44, 95% confidence interval 0.23 to 0.84), poor histological differentiation (0.20, 0.08 to 0.49), high mitotic counts (0.38, 0.15 to 0.97), tumour necrosis (0.45, 0.22 to 0.93) or to be of the ductal histological type (0.46, 0.22 to 0.95). They had low oestrogen receptor (0.29, 0.12 to 0.70) and progesterone receptor (0.35, 0.17 to 0.92) concentrations less often and had smaller S phase fractions (0.72, 0.55 to 0.96) than control cancers. CONCLUSIONS--Even after adjustment for the smaller size of screen detected breast cancers, their histological and cytometric features suggest low malignant potential. They may also be less likely to metastasise to axillary lymph nodes than cancers found outside screening.     

Overweight in relation to tumour size and axillary lymph node involvement in postmenopausal breast cancer patients—Differences between women invited to vs. not invited to mammography in a randomized screening trial

Objectives: Overweight is associated with advanced stage at diagnosis in breast cancer patients. This could be explained by specific tumour characteristics or tumour promoting factors in the obese, but a diagnostic delay could also be of importance. Mammographic screening has caused a change towards diagnosis of less advanced tumours. This study investigates invitation to mammographic screening and the association between overweight and tumour size/axillary lymph node involvement at breast cancer diagnosis in postmenopausal women. Methods: In 1976 a randomized mammographic screening trial, inviting 50% of all women aged 45–69 was set up in Malmö, Sweden. The present analysis examined overweight (body mass index ≥25) as a determinant for large tumours (>20 mm) and axillary lymph node involvement in postmenopausal women. These associations were studied separately in patients diagnosed prior to the mammographic screening trial, in invited women and in non-invited subjects (controls). In all, 2478 postmenopausal women were diagnosed with invasive breast cancer in these groups between 1961 and 1991. Logistic regression analysis allowed adjustment for other potential determinants of tumours size and axillary lymph node involvement. Results: In women diagnosed before the onset of the screening trial and in women not invited to mammography in the trial (controls), overweight was positively associated with large tumour size and axillary node involvement. There was no statistically significant association between overweight and these factors in women invited to mammographic screening. Conclusion: Invitation to mammographic screening may be particularly important for overweight postmenopausal women in order to detect breast tumours early.     

Breast cancer screening among Asian immigrant women in Canada

Objective: The objective of this study was to examine the pattern of breast cancer screening among Asian immigrant women aged 50–69 years and compare it with corresponding non-immigrant women in Canada. Methods: Data from the Canadian Community Health Survey cycle 2.1 (2003) were utilized. Self-reported screening histories were used as outcome variables: socioeconomic status and medical histories were used as predictive variables. Analyses were weighted to represent the target population. Multivariate logistic regression analyses were performed to compare the screening pattern among Asian immigrant women and corresponding non-immigrant Canadians. Results: In total, 508 Asian immigrant women were included in this study. The results suggest that 71% and 60% of Asian immigrant women reported ever having had and recent mammogram use, respectively, while the corresponding figures for non-immigrant women were 89% and 72%. The observed differences were statistically significant and could not be explained by confounding factors. The ability to speak one of the two official languages is an important barrier to mammography screening among Asian immigrant women. Conclusion: The findings show lower rates of mammography screening among Asian immigrant women in Canada. If breast screening is to remain a health policy objective in Canada, targeted efforts to increase the recruitment of Asian immigrant women need to be developed or strengthened.