Quantification of the effect of mammographic screening on fatal breast cancers: The Florence Programme 1990-96

Breast cancer cases diagnosed in women aged 50-69 since 1990 to 1996 in the City of Florence were partitioned into those who had been invited to screening prior to diagnosis and those who had not. All cases were followed up for vital status until 31 December 1999. The cumulative number of breast cancer deaths among the cases were divided by screening and invitation status, to give the rates of cancers proving fatal within a period of 8 years of observation (incidence-based mortality). We used the incidence-based mortality rates for two periods (1985-86, 1990-96), pre and during screening. The incidence-based mortality ratio comparing 1990-96 and 1985-86 was 0.50 (95% CI : 0.38-0.66), a significant 50% reduction. For noninvited women, compared to 1985-86, there was a 41% significant mortality reduction (RR=0.59, 95% CI : 0.42-0.82). The comparable reduction in those invited was a significant 55% (RR=0.45, 95% CI : 0.32-0.61). The incidence ratio of rates of cancers stage II or worse was close to one when the noninvited in 1990-96 were compared with 1985-86 (RR=0.97, 95% CI : 0.78-1.21). Excluding prevalent cases, the rate of stage II+ breast cancer cases was 42% lower in Screened women compared with the noninvited (RR=0.58, 95% CI : 0.45-0.74). This study confirmed that new treatments and the first rounds of the screening programme contributed to reducing mortality from breast cancer.     

Interval cancers in the Dutch breast cancer screening programme.

The nationwide breast cancer screening programme in The Netherlands for women aged 50-69 started in 1989. In our study we assessed the occurrence and stage distribution of interval cancers in women screened during 1990-1993. Records of 0.84 million screened women were linked to the regional cancer registries yielding a follow-up of at least 2.5 years. Age-adjusted incidence rates and relative (proportionate) incidences per tumour size including ductal carcinoma in-situ were calculated for screen-detected and interval cancers, and cancers in not (yet) screened women, comparing them with published data from the UK regions North West and East Anglia. In total 1527 interval cancers were identified: 0.95 and 0.99 per 1000 woman-years of follow-up in the 2-year interval after initial and subsequent screens respectively. In the first year after initial screening interval cancers amounted to 27% (26% after subsequent screens) of underlying incidence, and in the second year to 52% (55%). Generally, interval cancers had a more favourable tumour size distribution than breast cancer in not (yet) screened women. The Dutch programme detected relatively less (favourable) invasive cancers in initial screens than the UK programme, whereas the number of interval cancers confirms UK findings. Measures should be considered to improve the detection of small invasive cancers and to reduce false-negative rates, even if this will lead to increasing referral rates.     

Incidence and tumour stages of breast cancer in the region of Aachen, Germany

We present epidemiological data of female breast cancer in the region of Aachen (Germany) including incidence and tumour stages for the period 1996-1997. Furthermore, we compare epidemiological data from Aachen with data from the directly neighbouring Dutch region South-Middle Limburg before and after the introduction of a national mammographic screening programme. The field study of breast cancer was undertaken at the Institute of Pathology and Comprehensive Cancer Center at the University of Aachen, supported by the Federal Ministry of Health (Germany), using data files from the Cancer Registry Aachen. The patient's consent to collect all data concerning her epidemiological and social situation as well as information on the outcome of disease was obtained in 83.4% of all cases. The remaining 16.6% of the cases without a patient's consent are based on histopathological reports. Only those patients are included who were documented as residing in the region of Aachen at the time of diagnosis. Tumour cases were counted according to International Agency for Research on Cancer rules and tumour stages are classified according to UICC guidelines. Incidence rates are calculated as crude value, adapted to the European and World Standard population (ESR, WSR), and the age specific incidence is presented in 5-year intervals. The cumulative risk is assessed for a certain life span by summarizing the age-specific incidences. The age-standardized breast cancer incidence rate in Aachen was 94 per 100 000 women in 1996 and 90 cases of invasive breast cancer per 100 000 women in 1997 according to the ESR. The cumulative risk of developing breast cancer in the life span ranging from 0 to 74 years is approximately 8%. The stage distribution of breast cancer reveals only 4% favourable carcinomata in situ, but 12% advanced T4 tumours. T1 and T2 tumour stages count for about 40% and T3 tumour stages about 4%. Incidence rates and the tumour stages of breast cancer in the region of Aachen during 1996 and 1997 are similar to the data obtained from the directly neighbouring Cancer Center of the region South-Middle Limburg, in the Netherlands, in 1989/1990 before the beginning of the national breast cancer screening programme. However, major differences are found in terms of the incidence and the tumour stages between Aachen 1996/1997 and South-Middle Limburg 1995/1996 after the introduction of the mammographic screening. The incidence of female breast cancer in Aachen, Germany, was high and in the range of the data from other cancer registries in Europe without national screening programmes. The tumour stages at diagnosis in Aachen were not very favourable, especially in elderly women. An increase of the cancer incidence and a shift of the tumour stages to more favourable ones were observed in the neighbouring Dutch region of South-Middle Limburg, comparing data from 1989/90 and 1995/96. This is probably as a result of the national mammographic screening programme. As data from Aachen were similar to Limburg's data from 1989/90 before the mammographic screening was introduced, it will be important to follow and compare the cancer incidence and the tumour stages in the future.     

The Full Potential of Breast Cancer Screening Use to Reduce Mortality has not yet been Realized in the United States

OBJECTIVE: Breast cancer mortality has been declining in European countries and the United States since the early 1990s. Based on breast cancer screening programs in western European countries, the reduction in mortality results from a predictable pattern of increasing early-stage and subsequent declining incidence of late-stage cancers. The purpose of this study was to determine whether changes in the incidence of early-stage and late-stage breast cancers has occurred in the United States to suggest that a reduction in breast cancer mortality is the result of screening. METHOD: The analyses are based on women 50-69 years of age using 1990-1998 Surveillance, Epidemiology, and End Results data. Five indicators that are precursors to reductions in mortality are described: in situ breast cancer, T1 tumors (< 2 cm), stage II-IV tumors, lymph node-positive cancers, and locally advanced breast cancers (LABC). RESULTS: The rate of in situ tumors increased from 37.8 to 67.0 per 100,000 population and that of T1 tumors increased from 143.5 to 163.5 per 100,000 population during 1990-1998. The rates of stage II-IV tumors, lymph node-positive cancers, and LABC remained unchanged at about 120 per 100,000, 76 per 100,000, and 17 per 100,000 population, respectively. CONCLUSIONS: Although there has been an increase in early-stage breast cancers (in situ and T1 tumors), the prerequisite decline in late-stage cancers has not yet occurred in the United States--a pattern that was observed in European studies. Possible explanations include the lack of widespread mammography use during the 1980s and, therefore, insufficient elapsed time since mammography use has become more widespread.     

Breast cancer in New South Wales in 1972-1995: tumor size and the impact of mammographic screening.

To examine the use of mammographic screening in women in New South Wales (NSW), we measured uptake of initial mammograms and estimated the proportions of breast cancers that were screen detected. To see if mammographic screening has been associated with reductions in advanced breast cancers and mortality from breast cancer, we analyzed trends in age-specific and age-standardized breast cancer incidence and mortality from 1972 to 1995 and tumor size in 1986, 1989, 1992 and April to September 1995. Between 1984 and the end of 1995, an estimated 72% of NSW women in their 50s and 67% in their 60s had had at least 1 mammogram and, in 1995, an estimated 39% of invasive breast cancers in women in these age groups were detected by mammography. Before 1989, breast cancer incidence increased only slightly (+1.3% annually) but then, from 1990 to 1995, increased more rapidly (+3.1% annually). Between 1986 and 1995, rates of small cancers (< 1 cm) increased steeply by 2.7 times in women 40-49 years of age and 5.6 times in women 50-69 years of age. The incidence of large breast cancers (3+ cm), after little apparent change to 1992, fell by 17% in women 40-49 years of age and 20% in those 50-69 years of age to 1995. Breast cancer mortality increased slightly between 1972 and 1989 (+0.5% annually) but then fell (-2.3% annually) from 1990 to 1995. We concluded that breast cancer rates had been influenced in expected directions by the introduction of mammographic screening in women resident in NSW. We expect that recent falls in incidence of larger breast cancers and breast cancer mortality will become steeper as screening coverage increases in the second half of the 1990s.     

Impressive time-related influence of the Dutch screening programme on breast cancer incidence and mortality, 1975-2006

The aim of this study was to assess changes in the trends in breast cancer mortality and incidence from 1975 to 2006 among Dutch women, in relation to the implementation of the national breast cancer screening programme. Screening started in 1989 for women aged 50-69 and was extended to women aged 70-75 years in 1998 (attendance rate approximately >80%). A joinpoint Poisson regression analysis was used to identify significant changes in rates over time. Breast cancer mortality rates increased until 1994 (age group 35-84), but thereafter showed a marked decline of 2.3-2.8% per annum for the age groups 55-64 and 65-74 years, respectively. For the age group of 75-84 years, a decrease started in the year 2001. In women aged 45-54, an early decline in breast cancer mortality rates was noted (1971-1980), which is ongoing from 1992. For all ages, breast cancer incidence rates showed an increase between 1989 and 1993, mainly caused by the age group 50-69, and thereafter, a moderate increase caused by age group 70-74 years. This increase can partly be explained by the introduction of screening. The results indicate an impressive decrease in breast cancer mortality in the age group invited for breast cancer screening, starting to show quite soon after implementation.     

Prostate and breast cancer in four Nordic countries: A comparison of incidence and mortality trends across countries and age groups 1975–2013

In recent decades, management of prostate and breast cancer patients has changed considerably. The purpose of our study is to interpret patterns of prostate and breast cancer incidence and mortality in four Nordic countries across age groups and time periods. Prostate and breast cancer incidence and mortality data (1975–2013) were obtained from the NORDCAN database. Joinpoint regression models were used to identify changes in the trends. A more prominent increase in prostate than breast cancer incidence was observed. From the mid‐1990s, mortality rates in patients below 75 years of age have decreased for both cancers in all four countries. The relative decline in breast cancer mortality from 1985–1989 to 2009–2013 were largest in women under 50 years of age, with reductions in mortality rates ranging from 38% in Finland to 55% in Denmark. In the age group 55–74 years, mortality rates for prostate cancer declined more than for breast cancer in all countries except Denmark, ranging from 14% in Denmark to 39% in Norway. The substantial decrease in breast cancer mortality in women below regular screening age and the reductions in mortality from both cancers in Denmark from the mid‐1990s are consistent with beneficial contributions from improved treatment besides mammography screening and increased PSA testing. Alongside similar mortality decreases, the larger increases in prostate cancer incidence as compared to breast cancer indicate that a higher proportion of prostate cancer cases are overdiagnosed.     

Cancer incidence in a cohort of Ontario and Quebec women having bilateral breast augmentation

The possibility that women, who receive breast implants for cosmetic purposes, have increased long-term risks of developing cancer continues to be debated. The objective of our study was to prospectively examine cancer incidence among women who received breast implants. A cohort was assembled of 24,558 women, 18 years of age and older, who underwent bilateral cosmetic breast augmentation, and 15,893 women who underwent other cosmetic procedures in Ontario or Quebec between 1974 and 1989. These plastic surgery patients were selected from the same clinics as the implant population. Incident cancers were identified by linking to Canadian registry data up to December 31, 1997. In total, 676 cancers were identified among women who received breast implants compared to 899 expected based on general population rates (standardized incidence ratio (SIR) = 0.75; 95% confidence interval (CI) = 0.70-0.81). Overall cancer incidence rates among women who received breast implants were similar to that of the other plastic surgery patients (relative risk (RR) = 0.91, 95% CI = 0.81-1.02). However, women who received breast implants had lower breast cancer rates than the plastic surgery patients (RR = 0.64, 95% CI = 0.53-0.79). No increased risks were observed among the implant population for any of the other cancer sites examined. Comparisons involving only women who received breast implants found no association between long-term breast cancer incidence and implant site (submuscular vs. subglandular), fill (saline vs. silicone) or envelope (polyurethane-coated or not). In conclusion, women undergoing cosmetic breast augmentation do not appear to be at an increased long-term risk of developing cancer.     

Predicted long-term mortality reduction associated with the second round of breast screening in East Anglia

Randomized trials have demonstrated that mammographic screening can reduce breast cancer mortality. Our aim was to estimate the reduction in mortality expected from the East Anglian Breast Screening Programme. Breast screening achieves benefit by improving cancer prognosis (reducing tumour size, nodal involvement and possibly grade) through earlier diagnosis. We compared cancer prognosis between women invited for screening and those not yet invited in East Anglia, UK, in order to predict the mortality reduction achievable by screening, independently of any reduction due to changes in treatment and underlying disease. Participants (both invited and not-yet invited) were women eligible for invitation to first and second screens and diagnosed with invasive breast cancer in 1989-96. Death rates were predicted based on the observed distribution of tumour grade, size and node status amongst 950 cancers diagnosed following first invitation, up to and including at second screen (excluding those detected at first screening), and 451 cancers presenting symptomatically in women awaiting first invitation during the staggered introduction of screening, after adjustment for lead time amongst screen detected cases. For all ages, the ratio of predicted breast cancer mortality in the invited compared with the uninvited group was 0.85 (95% CI 0.78, 0.93). It was 0.93 (0.80, 1.08) for women aged 50-54 at diagnosis and 0.81 (0.72, 0.91) for those aged 55-64. We conclude that, by 2004, the second round of screening in East Anglia should reduce mortality by around 7% in women below age 55 at diagnosis, and by around 19% in those aged 55-64.     

Effect of mammographic service screening on stage at presentation of breast cancers in Sweden

BACKGROUND

Previous results have shown a reduction in mortality with service screening in Sweden on the order of 40%. If the rate of tumors at a later stage were similarly reduced, this would give further support to the mortality findings.

METHODS

The rates of lymph node‐positive cancers, of tumors >2 cm in pathological size, and of tumors of TNM stage II or worse before and after the introduction of screening were compared in 13 areas in Sweden, adjusted for changes in overall incidence during the period of study and stratified by age (40–49 and 50–69 years).

RESULTS

Data were obtained on a total of 23,092 cancers and 10,177,113 person‐years of observation. In women exposed to screening in the screening epoch, there was a significant 45% reduction in tumors of size >2 cm compared with the prescreening (relative risk [RR] = 0.55, 95% confidence interval [CI]: 0.46–0.66) in the 40–49 age group, and a 33% reduction in the 50–69 group (RR = 0.67, 95% CI: 0.62–0.72). For lymph node‐positive and stage II+ disease, there were smaller but still significant reductions. No reduction in incidence in later‐stage disease was observed in the unexposed women in the screening epoch.

CONCLUSIONS

Screening has significantly and substantially reduced the rates of larger tumors and lymph node‐positive breast cancer in Sweden, and the magnitude of the reduction is consistent with the reduction in breast cancer mortality. Cancer 2007. © 2007 American Cancer Society.     

Mammography Screening and Breast Cancer Mortality in New South Wales, Australia

OBJECTIVE: To investigate the relationship between utilisation of service mammography screening and breast cancer mortality in New South Wales (NSW) women. Setting : Population-based biennial mammography screening was progressively introduced in NSW from 1988, with active recruitment and re-invitation for women aged 50-69 years, and reached full geographic coverage by 1996. Biennial mammography screening participation has varied widely over time and by municipality. METHODS: Breast cancer mortality by age, period and municipality was obtained from the NSW Central Cancer Registry. Biennial mammography screening rates for the same strata were obtained from the BreastScreen NSW database. Temporal changes in breast cancer mortality for NSW were summarised as annual average declines using Poisson regression. Breast cancer mortality for 1997-2001 was examined in relation to lagged biennial screening rates by municipality, adjusted for age, area socio-economic and geographic indicators, and breast cancer incidence, also using Poisson regression. RESULTS: For the 50-69 year age group, the mean annual breast cancer mortality decline was 0.8% (not significant) for 1988-1994, and 4.4% (p < 0.0001) for 1995-2001. Statistically significant negative associations between breast cancer mortality in 1997-2001 and lagged biennial screening rates were found with the highest significance at a four-year lag for women aged 50-69 years ( p = 0.0003) and also for women aged 50-79 years (p c = 0.0002). From the regression coefficient, a 70% biennial screening rate is associated with 32% lower breast cancer mortality (compared to zero screening). CONCLUSIONS: The effect of population-based mammography screening on breast cancer mortality in NSW inferred using this method is consistent with results of trials and other service studies. This suggests that population-based mammography screening programs can achieve significant reductions in breast cancer mortality with adequate participation.     

Trends in cervical cancer in the Netherlands until 2007: Has the bottom been reached?

We explored trends in incidence and mortality of cervical cancer by age, stage and morphology, and linked the observed trends to screening activities. Data was retrieved from the Netherlands Cancer Registry during 1989–2007 (incidence) and Statistics Netherlands during 1970–2007 (mortality). Trends were evaluated by calculating the estimated annual percentage change (EAPC). Joinpoint regression analysis was used to detect changes in trends. Cervical intraepithelial neoplasia (CIN) detection rates were calculated by data from “the nationwide network and registry of histo‐ and cytopathology” during 1990–2006. Total age‐adjusted incidence rate (European standardized rate (ESR)) was 7.9 per 100,000 woman years in 2007. During 1989–1998, incidence rates decreased with an EAPC of ?1.3% (95% confidence interval (CI) ?2.2 to ?0.3), during 1998–2001 with ?6.7% (95% CI: ?16.4 to 4.1), and increased during 2001–2007 with 2.3% (95% CI: 0.4 to 4.2). Total mortality ESR was 1.9 per 100,000 woman years in 2007. Mortality rates decreased during 1970–1994 annually with ?4.1% (95% CI: ?4.6% to ?3.7%), and with ?2.6% (95% CI: ?3.8% to ?1.5%) during 1994–2007. The observed trend in total incidence is similar to the trend in squamous cell carcinomas in age group 35–54 years, suggesting that the observed trends are likely to be associated to changes in the screening program. This is supported by the trend in CINIII detection rates. In conclusion, incidence and mortality overall decreased and leveled off. On top of that there was an extra decrease that was compensated by a following recent increase in incidence, probably resulting from reorganization of the Dutch screening program.     

Clinical breast examination: preliminary results from a cluster randomized controlled trial in India

A cluster randomized controlled trial was initiated in the Trivandrum district (Kerala, India) on January 1, 2006, to evaluate whether three rounds of triennial clinical breast examination (CBE) can reduce the incidence rate of advanced disease incidence and breast cancer mortality. A total of 275 clusters that included 115,652 healthy women, aged 30-69 years, were randomly allocated to intervention (CBE; 133 clusters; 55,844 women) or control (no screening; 142 clusters; 59,808 women) groups. Performance characteristics (sensitivity, specificity, false-positive rate, and positive predictive value) of CBE were evaluated. An intention-to-treat analysis was performed for comparison of incidence rates between the intervention and control groups. Preliminary results for incidence are based on follow-up until May 31, 2009, when the first round of screening was completed. Of the 50,366 women who underwent CBE, 30 breast cancers were detected among 2880 women with suspicious findings in CBE screening that warranted further investigations. Sensitivity, specificity, false-positive rate, and positive predictive value of CBE were 51.7% (95% confidence interval [CI] = 38.2% to 65.0%), 94.3% (95% CI = 94.1% to 94.5%), 5.7% (95% CI = 5.5% to 5.9%), and 1.0% (95% CI = 0.7% to 1.5%), respectively. The age-standardized incidence rates for early-stage (stage IIA or lower) breast cancer were 18.8 and 8.1 per 100,000 women and for advanced-stage (stage IIB or higher) breast cancer were 19.6 and 21.7 per 100,000 women, in the intervention and control groups, respectively.     

The incidence of advanced breast cancer in the West Midlands, United Kingdom

Breast screening of the West Midlands women of 50-64 years started in 1988. Reductions in breast cancer deaths induced by mammography screening should be preceded by reductions in the incidence of advanced breast cancer. We estimated incidence trends in advanced breast cancer from 1989 to 2004. We extracted numbers of cases of breast cancer found in the West Midlands women aged 50-64 years from the Cancer Incidence in Five Continent database. We used published data for estimating the incidence of advanced breast cancer. Then, annual percent changes in incidence rates were computed using join point regression. The incidence rates of lymph node-positive breast cancer increased from 1989 to 1992. In 1993-1995, they decreased below the prescreening level, but from 1996 to 2000, they returned to prescreening levels and then stabilized. From 1989 to 2004, annual percent changes (95% confidence interval) were 2.2% (1.1-3.2%) for node-negative cancers and -0.7% (-1.9 to 0.4%) for lymph node-positive cancers. The incidence of cancer greater than 50 mm remained stable from 1989 to 2004 [annual percent change: 0.2% (-2.2 to 2.7%)]. Results from the West Midlands suggest that the breast screening program did not play a significant role in reductions in mortality caused by breast cancer.     

Increased incidence of invasive breast cancer after the introduction of service screening with mammography in Sweden

Screening with mammography has been shown to substantially reduce mortality from breast cancer. The incidence of invasive cancer will increase as screening starts, and it is desirable that it gradually returns to the same level as before screening. Age-specific incidence of invasive breast cancer in 11 Swedish counties, including 463,000 women aged 40-74 years, was analysed before and after the start of service screening with mammography. Incidence, as observed on average during 12.8 years from screening start, was compared to expected incidence based on the incidence during a 15-year period preceding screening start. The height of the incidence peak during the first screening round was increasing with increasing age, compatible with the accumulation in the population of slowly growing tumours by age. All analysed age groups showed an increased ratio between observed stabilised incidence 7-14 years after screening start and expected incidence. When relative risks were adjusted for lead time, the estimates were 1.54 (95% confidence interval [CI] 1.33-1.79) and 1.21 (95% CI 1.04-1.41) for the age groups 50-59 and 60-69 years, respectively. In the age groups 40-49 and 70-74, no change was observed. The findings were further confirmed by the observation of a disappearance in the screened population of the notch in the increasing trend of age-specific breast cancer incidence for the ages after menopause. This notch could indicate hormone-related retardation in tumour growth around menopause. It appears that many of these clinically insignificant, retarded tumours are detected with screening mammography.     

Population-based incidence and mortality cancer trends (1986-1997) from the network of Italian cancer registries.

The objective of this study was to analyse incidence and mortality cancer trends in the Italian Network of Cancer Registries (about 8,000,000 inhabitants) during the period 1986-1997. Included were 525,645 newly diagnosed cancers and 269,902 cancer deaths (subjects > 14 years). Joinpoints (points in time where trend significantly changes from linearity) were found and estimated annual percentage changes (EAPC) used to summarize tendencies. Overall cancer incidence increased in both sexes and cancer mortality significantly decreased (since 1991 among men). Lung cancer showed significantly decreasing incidence (EAPC = -1.4%) and mortality (EAPC = -1.6%) among men and increasing trends among women. In women, breast cancer incidence significantly increased (EAPC= +1.7%) and mortality decreased since 1989 (EAPC= -2.0%). Stomach cancer incidence and mortality decreased in both sexes. Prostate incidence sharply increased since 1991 and mortality decreased. Colon cancer incidence increased and rectum mortality decreased significantly in both sexes. Significant increases in incidence were also found for kidney (up to 1991 among men), urinary bladder, skin epithelioma, melanoma, liver (up to 1993 among men), pancreas, mesothelioma, Kaposi's sarcoma (up to 1995 among men), testis, thyroid, non-Hodgkin's lymphomas and multiple myeloma. Mortality significantly decreased for cancers of the oral cavity and pharynx, oesophagus, liver (women), larynx (men), bone, cervix (since 1990), central nervous system, urinary bladder, thyroid, Hodgkin's lymphomas and leukaemias (men). Non-Hodgkin's lymphoma mortality increased in both sexes. In conclusion, most of the changes seen can be explained as the effect of changes in smoking habits and of the extension of secondary prevention activities. The Italian health care system will also have to cope with growing cancer diagnostic and therapeutic needs due to population ageing.     

Trends in cervical cancer mortality in Korea 1993-2002: corrected mortality using national death certification data and national cancer incidence data

Cervical cancer is a major health problem for Korean women, accounting for 9.8% of new female cancer cases, even though incidence rates have been decreasing. The Korean cervical cancer mortality rate for 1993-2002 based on National Statistical Office data shows an increasing trend, but the actual rates are thought to have decreased by epidemiologists, clinicians and other cancer experts. To explain this gap and solve this problem, we corrected the number of cervical cancer deaths by comparing death certificate cases of unspecified uterine cancer data with the national cancer incidence databases of entire cancer registries in Korea. We used 2 different methods to make a correction. First, we considered "uterus, unspecified" deaths previously registered as "cervix, uterine" cases misclassified and added them to the cervical cancer deaths. Alternatively, we multiplied the total number of registered unspecified uterine cancer deaths by age-specific proportions of registered incident cervical cancer cases among all cancers and added the product to cervical cancer deaths. The overall corrected age-standardized cervical cancer mortality rates per 100,000 women decreased from 5.2 in 1993 to 3.9 in 2002 (estimated annual percentage change (EAPC): -4.05%, 95% CI: -4.88, -3.22). While cervical cancer mortality showed a decreasing tendency in women aged 30-69 years, it increased substantially in women aged > or =70 years (EAPC: 3.62%, 95% CI: 1.92-5.35). Results of this study will provide evidence-based foundation for the evaluation of the existing cervical cancer-screening programs.     

Favourable prognostic factors of subsequent screen-detected breast cancers among women aged 50-69

Most studies reporting more favourable biological features of screen-detected breast cancers compared with symptomatic or interval cancers include initial or prevalent screens and therefore may not indicate the real benefit of screening on breast cancer mortality. We conducted case-case comparisons within a cohort of eligible women (N=771 715) who were aged 50-69 between 1 January 1995 and 31 December 2003. A randomly selected sample of breast cancers (N=1848) diagnosed among these women were compared by detection method. Tumour characteristics of interval cancers (N=362) diagnosed after 6-24 months of a negative screen or symptomatic breast cancers (N=491) were compared with subsequent screen-detected breast cancers diagnosed within 6 months of a positive screen (N=995) using polytomous logistic regression. Tumours were evaluated for clinical presentation, histology and expression of hormone receptors. Women with symptomatic detected [odds ratio (OR)=7.48, 95% confidence interval (CI)=5.38-10.38] and interval cancers (OR=2.20, 95% CI=1.56-3.10) were more often diagnosed at stage III-IV versus I than women with rescreen-detected cancers. After adjusting for tumour size, women with symptomatic cancers had tumours of higher grade (OR=1.50, 95% CI=1.05-2.15) and mitotic score (OR=1.69, 95% CI=1.15-2.49) and women with interval cancers had tumours of higher mitotic score (OR=1.52, 95% CI=1.01-2.28) compared with women diagnosed at screening. Subsequent screen-detected cancers are not only detected at an earlier stage but are also less aggressive, leading to a better prognosis. As long-term mortality reduction for breast screening may depend on subsequent screens, our study indicates that mammography screening can be effective in women aged 50-69.     

Evaluation of The Netherlands breast cancer screening programme.

The Netherlands breast cancer screening programme for women aged 50-75 years was gradually implemented during 1989-1997. Short-term indicators for this mammography screening are 80% attendance (800 000 examinations yearly), and for the subsequent screening examinations 7.4 referrals for clinical assessment per 1000 women screened, 4.7 biopsies and 3.6 breast cancers detected. Breast cancer mortality in The Netherlands has been decreasing since 1997 after having been stable for decades. The challenge now is to disentangle the relative contributions of mammographic screening, earlier clinical diagnosis, less aggressive tumours, treatment advances and risk factors towards this decline.     

Assessment of the early impact of the population-based breast cancer screening programme in Florence (Italy) using mortality and surrogate measures

The aim of this study was to evaluate the effects by the end of 1999 of the Florence breast screening programme that started in 1990. Approximately 60000 women (aged 50-69 years) were enrolled from 1990 to 1993. Breast cancer cases diagnosed from 1990 to 1996 were partitioned by the method of detection, classified by their tumour size and nodal status and followed-up for mortality at on the 31 December 1999. Incidence-based mortality in the 50-74-year-old women and advanced carcinomas rates were assessed. Due to low compliance (approximately 60%) and the long enrollment phase, only approximately 35% of the total age-specific population person-years were screened. The number of invasive cases diagnosed was 1122, 17% higher than the 958 expected. After the prevalence screening, a reduction of approximately a quarter in advanced carcinomas was observed in the invited women (Odds Ratio (OR): 0.74; 95% Confidence Interval (CI): 0.55-0.98). In the period 1990-1999, 547 breast cancer deaths were observed: 78 (14%) occurred in women invited and half of these in never responders, 385 (70%) occurred in cases diagnosed before screening started. Disproportionate numbers of deaths occurred in women with advanced tumours. The 19% mortality reduction for the invited women was of borderline statistical significance (observed/expected (O/E) deaths: 0.81; 95% CI: 0.64-1.01); by a one-sided test the result would be unequivocally significant. The mortality reduction attributable to screening in the whole population over the 10-year period was 3.2%. The incidence-based mortality analysis confirmed the current follow-up time is too short for screening to have had a major effect on the breast cancer mortality trends. Screening performance might be improved by a higher level of compliance and shorter interval times, but the estimate of the mortality reduction for the invited and the lower rate of advanced carcinomas confirmed that the effect of the programme is in the expected direction.