Trends in breast cancer mortality, incidence, and survival, and mammographic screening in Tuscany, Italy

Breast cancer screening program in Lithuania: trends in breast cancer mortality before and during the introduction of the mammography screening programme

Abstract. Background.

Breast cancer is the most frequent oncological disease as well as the leading cause of cancer death among women worldwide. Decline in mortality in economically strong countries is observed. This decline is mostly related to early diagnosis (an improvement in breast cancer awareness and the mammography screening program (MSP)) and a more effective treatment. In the end of 2005, MSP started in Lithuania. The main aim of this article is to evaluate the breast cancer mortality during 22 years in Lithuania, as well as changes before the start of the MSP and during its implementation, in order to assess the influence of the MSP on mortality.

Materials and methods.

Analysis is based on data from the population-based Lithuanian Cancer Registry. Analysis of changes in mortality includes the period from 1998 to 2019. Age standardized mortality rates are calculated for assessment of changes. Joinpoint regression analysis is used.

Results.

Applying the segmental regression model, it was found that during the study period mortality was statistically significantly decreasing by -1.1% each year. Mortality among women under the age of 50 decreased both before and during the implementation of MSP. Mortality in the target population also was already decreasing until the implementation of the program, but a significant reduction in mortality was observed in this group since 2006.

Conclusions.

Overall breast cancer mortality is decreasing in Lithuania. After the implementation of MSP the largest reduction in mortality was observed in the target population, however, it is not as pronounced as it could be with the well-organized MSP.

Factors associated with locoregional and metastatic breast cancer at diagnosis in a Southern Portuguese registry in the period 2005-2012

Breast cancer (BC) is the most frequent malignancy in Portuguese women, and more than half of the registered cases live in the south of the country. The main of this study was to characterize patients with locoregional and metastatic incident BC living in the Southern Portuguese and Madeira regions in 2005-2012 according to demographic, clinical and contextual characteristics. Additionally it aimns to find the associations and relative influences of these factors with locoregional or metastatic disease at diagnosis. After a descriptive approach, binary logistic regression models were used to estimate factors related to the presence of metastatic disease at diagnosis. A final multiple regression model was developed and presented graphically as a nomogram. The median age at diagnosis was 60.84 years, being statistically lower in locoregional cases (P < 0.001). Most patients presented a locoregional disease (78.4%) of unspecified location (44.5%) and had a ductal carcinoma (73.1%). The Lisbon region represented 50.5% of the analyzed cases. Metastatic disease significantly decreased over the period under analysis ( ≈ 7%/year). Demographic (age at diagnosis ≥ 50 years), clinical (lobular and 'other' morphologies, unspecified location) and contextual (residence in Portalegre) characteristics were statistically correlated with the presence of metastatic disease at the time of BC diagnosis in univariate logistic regression, with all but the last maintaining their significance in a multivariate model. Cases with metastatic BC disease at diagnosis are decreasing; however, additional information on their characteristics can improve the alignment of public health strategies, thus strengthening this trend, and contributing to the development of a graphically tailored screening tool.

The impact of mammography screening programmes on incidence of advanced breast cancer in Europe: a literature review

Background

Observational studies have reported conflicting results on the impact of mammography service screening programmes on the advanced breast cancer rate (ABCR), a correlation that was firmly established in randomized controlled trials. We reviewed and summarized studies of the effect of service screening programmes in the European Union on ABCR and discussed their limitations.

Methods

The PubMed database was searched for English language studies published between 01-01-2000 and 01–06-2018. After inspection of titles and abstracts, 220 of the 8644 potentially eligible papers were considered relevant. Their abstracts were reviewed by groups of two authors using predefined criteria. Fifty studies were selected for full paper review, and 22 of these were eligible. A theoretical framework for their review was developed. Review was performed using a ten-point checklist of the methodological caveats in the analysis of studies of ABCR and a standardised assessment form designed to extract quantitative and qualitative information.

Results

Most of the evaluable studies support a reduction in ABCR following the introduction of screening. However, all studies were challenged by issues of design and analysis which could at least potentially cause bias, and showed considerable variation in the estimated effect. Problems were observed in duration of follow-up time, availability of reliable reference ABCR, definition of advanced stage, temporal variation in the proportion of unknown-stage cancers, and statistical approach.

Conclusions

We conclude that much of the current controversy on the impact of service screening programmes on ABCR is due to observational data that were gathered and/or analysed with methodological approaches which could not capture stage effects in full. Future research on this important early indicator of screening effectiveness should focus on establishing consensus in the correct methodology.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4666-1) contains supplementary material, which is available to authorized users.

Impact of breast cancer screening in a population with high spontaneous coverage with mammography

OBJECTIVE

The impact of organized screening programs on breast cancer (BC) mortality is unclear in an era of high spontaneous referral of women to mammography. The aim of this study was to analyze if the introduction of mammographic screening programs reduced BC mortality in the Veneto region, Italy, despite already widespread spontaneous access to mammography.

METHODS

In Veneto, screening was introduced in different years between 1999 and 2009 across 21 local health units (LHUs), inviting asymptomatic women aged 50-69 years to undergo mammography biennially. We compared BC mortality for the 1995-2014 period of women aged 40-49 and 50-74 years who were resident in LHUs where screening programs started in 2003 (early LHUs) with women resident in LHUs where screening was introduced later (late LHUs). Poisson regression models were applied to incidence-based mortality (IBM), including only deaths from BC arising within the screening period.

RESULTS

In the prescreening period and until 2010, BC mortality rates in early and late LHUs were similar in both age groups. In the last study period (2010-2014), we observed a 10% decrease in overall BC mortality in early compared to late LHU, limited to women aged 50-74 years. IBM was reduced by 8% (95% CI 1%-16%) in the overall study period and by 16% (6%-25%) in 2010-2014.

CONCLUSIONS

In the Veneto region, screening programs were associated with a significant impact on BC-specific mortality; such effect appeared at least 8 years after screening implementation.

Regional Estimates of Breast Cancer Burden in Italy

Aims and background

Breast cancer is the most common cancer and the leading cause of cancer death among women. Knowledge of the present and future burden of the disease at a regional and national scale is a major issue in Italy, where the frequency and coverage of screening programs vary considerably across the country. This study presents estimates and projections of the female breast cancer incidence, prevalence and mortality for Italy and all Italian regions in the period 1970-2010.

Methods

The estimates were obtained by applying the MIAMOD method, a statistical back-calculation approach to derive incidence and prevalence figures from mortality and relative survival data. Published data from the Italian cancer registries were modelled to obtain regional and national estimates of breast cancer survival.

Results

Breast cancer mortality has been declining from the late 1980s in the northern-central regions and from the mid 1990s in the southern regions Puglia, Sicilia and Sardegna. Stable mortality rates are estimated for the other southern regions in the 2000's first decade. The incidence rate in Italy is estimated as increasing until the late 1990s, and stable thereafter (93 per 100,000). The incidence curve is also estimated to flatten in many northern-central regions from the late 1990s or later. Rising incidence trends are estimated in all southern regions, with the exception of Puglia. About 8,500 deaths, 37,000 new diagnoses and 416,000 prevalent cases for breast cancer are estimated among Italian women in 2005. In the same year, the proportion of prevalent cases in the northern area (1,221 per 100,000) is about twice that estimated in the South (685 per 100,000).

Discussion

The geographical variation in female breast cancer burden can be explained by the unequal distribution of screening. A more widespread screening activity in the southern regions would help to bridge the gap between northern-central and southern regions. Continuous monitoring of regional epidemiological indicators for breast cancer is crucial to evaluate the effect of different health measures taken to control breast cancer in Italy.

Mammography, Martin Yaffe, and me: response and appreciation

I thank Dr. Martin Yaffe for his many constructive comments in his thoughtful review of my previous invited editorial, providing valuable insights into the complex and controversial issues of the current mammography debate. [...]

Screening mammography benefit controversies: sorting the evidence

Numerous clinical studies have confirmed that screening women age 40 years and older reduces breast cancer mortality by 30% to 50%. Several factors including faster breast cancer growth rates and lower breast cancer incidence among younger women, as well as shorter life expectancy and more comorbid conditions among older women, should also be considered in screening guidelines. Annual screening beginning at age 40 years and continuing with no upper age limit, as long as a woman has a life expectancy of at least 5 years and no significant comorbid conditions, is currently recommended.

The impact of mammographic screening on breast cancer mortality in Europe: a review of observational studies

OBJECTIVES

To assess the impact of population-based mammographic screening on breast cancer mortality in Europe, considering different methodologies and limitations of the data.

METHODS

We conducted a systematic literature review of European trend studies (n = 17), incidence-based mortality (IBM) studies (n = 20) and case-control (CC) studies (n = 8). Estimates of the reduction in breast cancer mortality for women invited versus not invited and/or for women screened versus not screened were obtained. The results of IBM studies and CC studies were each pooled using a random effects meta-analysis.

RESULTS

Twelve of the 17 trend studies quantified the impact of population-based screening on breast cancer mortality. The estimated breast cancer mortality reductions ranged from 1% to 9% per year in studies reporting an annual percentage change, and from 28% to 36% in those comparing post- and prescreening periods. In the IBM studies, the pooled mortality reduction was 25% (relative risk [RR] 0.75, 95% confidence interval [CI] 0.69-0.81) among invited women and 38% (RR 0.62, 95% CI 0.56-0.69) among those actually screened. The corresponding pooled estimates from the CC studies were 31% (odds ratio [OR] 0.69, 95% CI 0.57-0.83), and 48% (OR 0.52, 95% CI 0.42-0.65) adjusted for self-selection.

CONCLUSIONS

Valid observational designs are those where sufficient longitudinal individual data are available, directly linking a woman's screening history to her cause of death. From such studies, the best 'European' estimate of breast cancer mortality reduction is 25-31% for women invited for screening, and 38-48% for women actually screened. Much of the current controversy on breast cancer screening is due to the use of inappropriate methodological approaches that are unable to capture the true effect of mammographic screening.

Advanced breast cancer incidence following population-based mammographic screening

BACKGROUND

Breast cancer mortality is declining in many Western countries. If mammography screening contributed to decreases in mortality, then decreases in advanced breast cancer incidence should also be noticeable.

PATIENTS AND METHODS

We assessed incidence trends of advanced breast cancer in areas where mammography screening is practiced for at least 7 years with 60% minimum participation and where population-based registration of advanced breast cancer existed. Through a systematic Medline search, we identified relevant published data for Australia, Italy, Norway, Switzerland, The Netherlands, U.K. and the U.S.A. Data from cancer registries in Northern Ireland, Scotland, the U.S.A. (Surveillance, Epidemiology and End Results (SEER), and Connecticut), and Tasmania (Australia) were available for the study. Criterion for advanced cancer was the tumour size, and if not available, spread to regional/distant sites.

RESULTS

Age-adjusted annual percent changes (APCs) were stable or increasing in ten areas (APCs of -0.5% to 1.7%). In four areas (Firenze, the Netherlands, SEER and Connecticut) there were transient downward trends followed by increases back to pre-screening rates.

CONCLUSIONS

In areas with widespread sustained mammographic screening, trends in advanced breast cancer incidence do not support a substantial role for screening in the decrease in mortality.

Impact of a programme of mass mammography screening for breast cancer on socio-economic variation in survival: a population-based study

Background

After a systematic mass mammography breast cancer screening programme was implemented between 1991 and 1996 (attendance 80%), we evaluated its impact on survival according to socioeconomic status (SES).

Methods

We studied survival rates up to 1-1-2005 for all consecutive breast cancer patients aged 50–69 and diagnosed in the period 1983–2002 in the area of the Eindhoven Cancer Registry (n = 4939). Multivariate analyses were performed using Cox regression analysis.

Results

The proportion of breast cancer patients with a low SES decreased from 22% in 1983–1990 to 14% in 1997–2002 when attendance was 85%. The proportion of newly diagnosed patients with stage III or IV disease in 1997–2002 was only 10% compared to 14% in 1991–1996 and 26% in 1983–1989 (P < 0.0001). Stage distribution improved for all socio-economic groups (P = 0.01). Survival was similar for all socio-economic groups in 1983–1990, but after the introduction of the screening programme women with low SES had lower age- and stage-adjusted survival rates (HR 2.0, 95%CI: 1.3–3.0). Survival was better for patients diagnosed in 1997–2002 compared to 1983–1990 for all socioeconomic strata; it was substantially better for the high SES group (HR 0.36, 0.2–0.5) compared to the lowest SES (HR 0.77, 0.6–1.1).

Conclusion

Although survival improved for women from each of the socio-economic strata, related to the high participation rate of the screening programme, women from lower socio-economic strata clearly benefited less from the breast cancer screening programme. That is also related to the higher prevalence of comorbidity and possibly suboptimal treatment.

Population-based mammography screening and breast cancer incidence in New South Wales, Australia

OBJECTIVE

To analyse breast cancer incidence trends in New South Wales (NSW), Australia, in relation to population-based mammography screening targeting women aged 50 to 69 years.

METHODS

Trends in age-specific incidence of invasive breast cancers in NSW women aged > or = 40 years were examined in relation to mammography screening rates and screening cancer detection rates.

RESULTS

Incidence of invasive breast cancer in NSW women increased in all age-groups over 1972 to 2002. The incidence trend for women aged 50 to 69 years showed that the steepest rise was associated with increased participation in population-based mammography screening, which was implemented from 1988 and achieved state-wide coverage in 1995. The elevated incidence of invasive cancer significantly exceeded pre-screening levels, and persisted after rates of initial screens declined. This elevated incidence was sustained by the contribution of cancers diagnosed through subsequent screening, and resulted from increased cancer detection rates in subsequent screens.

CONCLUSIONS

The recent increase in invasive breast cancer incidence in NSW is associated with mammography screening, and occurred mostly in the target age-group women. Persistence of higher incidence after 1994 was not explicable by inflation of cancer incidence due to detection of prevalent screen cases, but was associated with a trend of increased cancer detection rates in subsequent screening rounds, probably consequent to quality improvements in mammography screening diagnosis.

Breast cancer incidence, mortality and survival in the Umbria region of Italy (1978–1999)

Recent incidence, mortality and survival rates of female invasive breast cancer in the Umbria region were compared with data of 20 years ago and with data from other Italian Registries. Incidence data, derived from an ad hoc survey and from cancer registry records, were analysed for the periods 1978-1982 and 1994-1999; mortality trend rates were calculated based on data from official publications and the variation was assessed by joinpoint analysis. Fifteen-year survival rates, observed, relative and age-adjusted, were also calculated. Compared with the years 1978-1982, the age-adjusted incidence rates rose during 1994-1999, while age-adjusted mortality rates decreased in this latter period. Incidence and mortality rates specific for each age group showed a constant increase with age, in both periods of observation, especially among women from 50 to 75 years of age. The 5-year relative survival rates increased 17%, rising from 0.71 in 1978-1982 to 0.86 in 1994-1998; the survival improvement was evident among women aged 45-54, and 65-74. Age-adjusted incidence and mortality rates in Umbria were lower than in other Italian Registries and survival rates showed a better prognosis for breast cancers diagnosed in Umbria in the period 1994-1998. In conclusion, the 1994-1998 decline in breast cancer mortality and the survival improvement may in part reflect the effectiveness of earlier detection by mammography and the progress in treatments. Genetic and lifestyle factors along with the improvement in diagnosis, and in quality of data collection and classification could have determined the recorded increase in breast cancer incidence.

Breast cancer mortality trends in two areas of the province of Florence, Italy, where screening programmes started in the 1970s and 1990s

We compared breast cancer mortality rates in the period 1985-2000 in two areas of the province of Florence, Italy, where breast cancer screening programmes started in the 1970s (early screening (ES) area) and in 1990s (late screening (LS) area). The overall age-standardised mortality decreased in the whole period by 40.9% in the ES area (P<0.001), and by 11.3% in the LS area (P=0.030). Significant decreases in the ES area were detected in groups aged 45-54 years (61.1%; P= 0.018) and 65-74 years (44.7%; P= 0.049), whereas in the LS area no significant decrease was detected in any age group. The relatively low compliance in the first years of the programme in both areas, and the long enrollment period in the LS area could have reduced the effect on mortality. Our findings suggest that the drop in mortality in the ES area (41%) could be explained by both service screening and better care. The slight decrease in mortality in the LS area (11%) could be mainly due to better care. A reduction of about 30% is attributable to screening in the ES area over the period 1985-2000.

Initiation of population-based mammography screening in Dutch municipalities and effect on breast-cancer mortality: a systematic review

BACKGROUND

More than a decade ago, a mammography screening programme for women aged 50-69 years was initiated in the Netherlands. Our aim was to assess the effect of this programme on breast-cancer mortality rates.

METHODS

We examined data for 27948 women who died of breast-cancer aged 55-74 years between 1980 and 1999 (30560 cases until 2001). We grouped individuals into 93 clusters, depending on where they lived, and analysed data by use of national population statistics. We analysed time trends in breast-cancer mortality, adjusting for gradual implementations at municipality level, taking as year 0 the month and year in which screening began in a particular municipality. We used a Poisson regression model to estimate the time at which the trend started to turn. We assessed indirectly whether this turning point was related to initiation of screening or adjuvant systemic therapy in four clusters defined according to when screening was implemented.

FINDINGS

Compared with rates in 1986-88, breast-cancer mortality rates in women aged 55-74 years fell significantly in 1997 and subsequent years as predicted, reaching -19.9% in 2001. Mortality rates had been increasing by an annual 0.3% until screening was introduced; thereafter we noted a decline of 1.7% per year (95% CI 2.39-0.96) in women aged 55-74 years and of 1.2% in those aged 45-54 (2.40 to 0.07). The turning point in mortality trends arose at around year 0. Adjuvant systemic therapy is unlikely to be the cause of this turning point, since the mortality rates continued to rise up to 1 year after implementation in municipalities where screening began after 1995.

INTERPRETATION

Routine mammography screening can reduce breast-cancer mortality rates in women aged 55-74 years.

Time trends in cancer incidence and mortality in central Italy

Time trends in cancer incidence and mortality represent an essential tool for monitoring the changes in population lifestyle and in the environmental risks and the effectiveness of the health system on cancer control in a specific area. During 1985-1997 82 506 malignant tumours were diagnosed in the Tuscany Cancer Registry, central Italy (about 1 200 000 inhabitants) and 54 979 cancer deaths registered in the period 1985-1999 by the Regional Mortality Registry were analysed. A statistically significant decrease in incidence was evidenced for stomach and gallbladder in both sexes, and for oesophagus, larynx and lung among males. Significant increases were documented for melanomas of the skin, kidney and non-Hodgkin's lymphoma in both sexes for colon, prostate and Kaposi's sarcoma among males and for breast, thyroid and multiple myeloma among females. Mortality decreased significantly for stomach and thyroid in both sexes and for oral cavity and pharynx, oesophagus, rectum, larynx, lung, bone, prostate, testis and Hodgkin's disease among males and colon, gallbladder and breast among females. Mortality increased for soft tissue, brain and multiple myeloma. In conclusion, most of these data can be explained as the effect of the modifications that occurred in smoking habits between the sexes and as the consequence of the primary and secondary prevention activities that are ongoing in the area.

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.

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.