Time trends in breast cancer survival: experience in a single centre, 1975-89

Endocrine disrupting chemicals and breast cancer cells

Many hundreds of endocrine disrupting chemicals (EDCs) have been measured as entering human breast tissue from a range of environmental sources, and this review focuses on discussion of mechanisms by which such EDCs may be contributing to the globally rising incidence of breast cancer. Many of the distinguishing features of breast cancer may be accounted for by EDC exposure, including, but not limited to, the fact that many EDCs possess estrogenic activity and exposure to estrogen is a main risk factor for breast cancer. Studies of the actions of EDCs in human breast cancer cells are aided by use of the conceptual framework of the hallmarks of cancer, and, acting by a variety of genomic and nongenomic mechanisms, EDCs have now been shown to enable all the hallmarks of cancer to develop in human breast cancer cells. Many studies report that hallmarks can develop at concentrations which are within the range of those measured in human breast tissues, especially when added as mixtures. The varied levels of different EDCs measured in individual breast tissue samples together with the overlapping and complementary mechanisms of action of the EDCs imply that thematic mechanisms will be driven inevitably by different chemical mixtures. Despite the complexity, EDCs do need to now be acknowledged as a risk factor for breast cancer in order for preventative strategies to include reduction in EDC exposure.

Disparities in breast cancer mortality trends between 30 European countries: retrospective trend analysis of WHO mortality database

OBJECTIVE

To examine changes in temporal trends in breast cancer mortality in women living in 30 European countries.

DESIGN

Retrospective trend analysis. Data source WHO mortality database on causes of deaths Subjects reviewed Female deaths from breast cancer from 1989 to 2006

MAIN OUTCOME MEASURES

Changes in breast cancer mortality for all women and by age group (<50, 50-69, and >or=70 years) calculated from linear regressions of log transformed, age adjusted death rates. Joinpoint analysis was used to identify the year when trends in all age mortality began to change.

RESULTS

From 1989 to 2006, there was a median reduction in breast cancer mortality of 19%, ranging from a 45% reduction in Iceland to a 17% increase in Romania. Breast cancer mortality decreased by >or=20% in 15 countries, and the reduction tended to be greater in countries with higher mortality in 1987-9. England and Wales, Northern Ireland, and Scotland had the second, third, and fourth largest decreases of 35%, 29%, and 30%, respectively. In France, Finland, and Sweden, mortality decreased by 11%, 12%, and 16%, respectively. In central European countries mortality did not decline or even increased during the period. Downward mortality trends usually started between 1988 and 1996, and the persistent reduction from 1999 to 2006 indicates that these trends may continue. The median changes in the age groups were -37% (range -76% to -14%) in women aged <50, -21% (-40% to 14%) in 50-69 year olds, and -2% (-42% to 80%) in >or=70 year olds.

CONCLUSIONS

Changes in breast cancer mortality after 1988 varied widely between European countries, and the UK is among the countries with the largest reductions. Women aged <50 years showed the greatest reductions in mortality, also in countries where screening at that age is uncommon. The increasing mortality in some central European countries reflects avoidable mortality.

Is the biology of breast cancer changing? A study of hormone receptor status 1984-1986 and 1996-1997

Using archived tumours, those from 1984–1986 and 1996–1997 underwent immunohistochemistry for hormone receptors and grade analysis. A significant shift towards more ER-positive and low-grade disease was found; this appears to reflect screening practices, but could still influence survival.

A 13-year follow-up of patients with breast cancer presenting to a District General Hospital breast unit in southeast England

The purpose of this clinical cohort study was to examine long-term survival in groups of screen-detected and symptomatic breast cancer patients attending a specialist breast unit, and to determine the factors affecting this survival. A total of 3239 breast cancer cases (1252 screen-detected and 1987 symptomatic) diagnosed between 1989 and 2002 were followed up until the end of 2002, and breast cancer-specific survival was examined in the screened and symptomatic groups, in relation to patient age, tumour size, nodal status and histological grade. Long-term survival in this clinical cohort was high. Relative survival values in the symptomatic group were similar to population-based estimates for southeast England derived from data held at the Thames Cancer Registry, whilst survival values in the screening group were 11-12 percentage points higher at 4 years after diagnosis and onwards. Ten-year relative survival estimates were 88% in the screening group and 77% in symptomatic cases. In groups of comparable age, the difference in breast cancer-specific survival at 10 years was 19 percentage points. Survival was significantly related to tumour characteristics (size, nodal status and grade), but not to morphological tumour type or deprivation score of the subject. After adjustment for other factors, the difference in survival between the two groups was much attenuated and became statistically non-significant. The higher survival seen in the screening group can be almost entirely accounted for in terms of the detection of early stage and lower grade tumours which screening provides.

Trends in breast cancer mortality in Asturias, Spain

While breast cancer mortality rates are subsiding or beginning to decline in many western countries, in Spain they are increasing. We have studied breast cancer mortality rates in Asturias (Spain) by using the age-period-cohort model for the period of 1975-1994. There was an increase in the adjusted rates. The increase of relative risk of death in the period 1990-1994, in relation to that in 1975-1979, was 43%. There is a tendency for successive cohorts to have higher age-specific rates than previous cohorts. Trends in breast cancer mortality rates have been driven predominantly by birth cohort rate trends over the last decades in Asturias, suggesting that the changes in breast cancer mortality have been largely influenced by changes in aetiological factors.