Large differences in patterns of breast cancer survival between Australia and England: A comparative study using cancer registry data

Abstract

Survival from breast cancer in the UK is lower than in other countries in Western Europe, the USA and Australia. However, these international differences have not yet been examined in relation to tumor characteristics, treatment, screening history or other prognostic factors. We calculated relative survival by age, period of diagnosis, category of unemployment and extent of disease for women diagnosed with breast cancer during the period 1980–2002 in New South Wales (Australia) and West Midlands (England). National cancer registry data for each country for the period 1990–1994 were also examined. The excess hazard ratio was modeled as a function of prognostic covariables. Survival in Australia and New South Wales was higher than in England and West Midlands, respectively. In both regions, survival was lower for more deprived women and for the elderly. These differences were greater in West Midlands. Survival from localized and regional disease in New South Wales was higher than in West Midlands, but survival from metastatic disease was similar. Differences in breast cancer survival are unlikely to be entirely due to differences in data quality or to limitations of the analyses, although the measure of extent of disease used may not have been adequate to elucidate the effect of stage fully. One possible causal explanation is that the management of breast cancer differs between these regions. Further research should acquire better data on stage and investigate the effect of comorbidity and of patterns of care upon the difference in breast cancer survival between England and Australia. © 2008 Wiley‐Liss, Inc.

Impact of deprivation on breast cancer survival among women eligible for mammographic screening in the West Midlands (UK) and New South Wales (Australia): Women diagnosed 1997–2006

“…Survival amongst affluent women whose cancer was diagnosed via screening was very high (97% 4 years after diagnosis) and very similar in West Midlands and New South Wales. This is the only study to have shown a group of Australian women with similar survival to a group of UK counterparts; previous studies have all shown a large and persistent survival disadvantage for all groups of women diagnosed in the UK . This was, however, the only group of women in which survival was similar.…”

“…In each region, all tumour records were linked to an ecologically defined deprivation category based on the quintile of the regional distribution of the percentage of unemployment in their small area of residence. We used unemployment because it is an internationally comparable measure of deprivation and because we have previously shown that differences in survival by deprivation assessed with the unemployment rate are similar to those measured with two highly validated and locally defined deprivation measures . We used the smallest geographic areas available for the 2001 census to maximise the accuracy of the ecological data in each country.…”

Are international differences in breast cancer survival between Australia and the UK present amongst both screen‐detected women and non‐screen‐detected women? survival estimates for women diagnosed in West Midlands and New South Wales 1997–2006

“…Examining survival by screening status has the potential to shed further light on whether international differences are more likely to be due to tumour or patient factors or to other factors relating to the healthcare women receive. We have previously identified these as possible explanations for socioeconomic differences, but they also may explain international variations in survival …”

Breast cancer survival and stage at diagnosis in Australia, Canada, Denmark, Norway, Sweden and the UK, 2000-2007: a population-based study

“…Population-based comparisons of breast cancer survival by stage have generally been limited to pair-wise contrasts between countries with similar registration processes (Christensen et al , 2004; Jensen et al , 2004; Woods et al , 2009), or ‘high-resolution' studies that abstract stage from the medical records of large, representative samples of patients from cancer registries (Sant et al , 2003; Allemani et al , 2013). International high-resolution studies are costly and time-consuming, and dependent on the accessibility of medical records.…”