Breast cancer in Wales: time trends and geographical distribution

Abstract

Background: Breast cancer is the second commonest malignancy in the world. In 2012, approximately 522,000 women died of breast cancer across the world. The aim of this study is to provide an up-to-date analysis of time trends in incidence, geographical distribution, survival and mortality from breast cancer in Wales.

Methods: Breast cancer cases registered between 1985 and 2012 were identified from the Welsh Cancer Intelligence and Surveillance Unit (WCISU). A Poisson regression model was fitted to assess temporal trends and rate ratios (RR) and 95% confidence intervals (CI) were determined and compared in relation to age, geographical distribution and mortality across time periods.

Results: A total of 60,227 women diagnosed with breast cancer were registered with the Welsh cancer registry between 1985 and 2012. The age-standardised incidence rate of breast cancer was 113.4 per 100,000 populations over the entire study period. There has been a significant increase in the incidence of breast cancer over the study period, although a slight decline was recorded towards the end of the study. There is a considerable regional variation in incidence, with a higher incidence rate in the rural areas compared to urban areas (P<0.001). One- and five-year relative survival improved from 83.3 and 64.2 respectively in 1985-1989 to 91.1 and 78.8 respectively in 2000-2004. There has also been a considerable improvement in relative survival across all age groups. Mortality has improved over the study period with the most dramatic decline in the age groups 45-54 and 55-64 years (P<0.001).

Conclusions: There has been a significant increase in the incidence of breast cancer in Wales over the last three decades, which is likely to be partly due to the introduction of the National Health Service Breast Screening Programme. Breast cancer incidence is higher in rural areas than urban areas and lower incidence was seen in more deprived areas. There was a considerable decline in mortality rate across almost all age groups, especially in recent years. However, women over the age of 65 years had poorer outcome throughout the study period.

Keywords: Breast cancer; Wales; incidence; mortality; survival.

Figure 1

Time trends in incidence rates of breast cancer in Wales, 1985-2012.

Figure 2

Time trends in breast cancer by age in Wales, 1985-2012.

Figure 3

One- and five-year relative survival from breast cancer in Wales.

Figure 4

One-year relative survival across age groups in Wales.

Figure 5

Five-year relative survival across age groups in Wales.

Figure 6

European age-standardised mortality rates per 100,000 populations in Wales.

Figure 7

Time trends in mortality by age in Wales, 1985-2012.