Survival rates for four major cancers are lower in the UK (excluding Scotland) than they are in Australia, Canada, Sweden and Norway, and on a par with those of Denmark, a pattern that reflects diagnosis and treatment differences of these countries, said researchers.
The study, from the International Cancer Benchmarking Partnership (ICBP), appears in the 22 December online issue of the The Lancet.
In their background information the authors explain that cancer survival rate is a key measure of the effectiveness of healthcare systems in a nation or region and highlighting differences is one way to stimulate change to raise standards and reduce inequalities.
For this study, the first in a series, a working group of ICBP researchers compared the cancer survival rates of four major cancers – breast, ovarian, colorectal, and lung – in 12 jurisdictions in six countries: Australia, Canada, Denmark, Norway, UK (England, Wales and Northern Ireland, but not Scotland) and Sweden.
The data covered 2.4 million adults diagnosed with primary colorectal, lung, breast (women), or ovarian cancer between 1995 and 2007, with follow-up to the end of December 2007.
The researchers prepared their estimates of 1 and 5 year relative survival rates in 252 “life tables” controlled for background mortality by age, sex and calendar year.
The findings show that:
- Relative survival for all four cancers improved in all countries during 1995 to 2007.
- However, it was persistently higher in Australia, Canada and Sweden.
- Survival was intermediate in Norway, and lower in Denmark and the UK (England, Northern Ireland, and Wales).
- For example, in the case of bowel cancer, there was more than 12% difference in survival rates between the lowest performer, the UK, and the highest performer, Australia.
- And in the case of lung cancer, only 8.8% of UK patients survived until 5 years after diagnosis compared with 18.4% in Canada.
- Differences in survival rates were particularly noticeable for the first year after diagnosis and for patients aged 65 years and older.
- For breast cancer the disparities were much narrower for all ages, but much less so or not at all for the other cancers (for breast cancer the international differences narrowed from about 9% to 5% for 1-year survival and from about 14% to 8% for 5-year).
- For colorectal cancer, the disparities narrowed only for patients aged 65 and over.
The researchers conclude that these “up-to-date survival trends show increases” but also “persistent differences” among countries.
“Trends in cancer incidence and mortality are broadly consistent with these trends in survival,” they write, and “data quality and changes in classifications are not likely explanations” for these disparities in survival rates.
“The patterns are consistent with later diagnosis or differences in treatment, particularly in Denmark and the UK, and in patients aged 65 years and older,” they add.
Lead author Professor Michel Coleman, of the London School of Hygiene and Tropical Medicine, told the media it is the overall pattern that matters when we are trying to get a clear picture of what is happening so we can improve systems.
It is not a case of looking at particular doctors and specialists, but “how people are channelled through” the healthcare system “to optimal treatment”, he explained.
Sara Hiom, of Cancer Research UK, told the BBC that while it was encouraging to see rates improving, we need to look more closely at the differences.
She said when the government reviews its cancer strategy it needs to keep focusing on early diagnosis and improving equitable access to treatment. Reliable and consistent data is crucial to helping understand the problem and pinpointing the cause of the gap between the UK and other countries, she added.
The study was funded by the Department of Health for England and Cancer Research UK.
“Cancer survival in Australia, Canada, Denmark, Norway, Sweden, and the UK, 1995-2007 (the International Cancer Benchmarking Partnership): an analysis of population-based cancer registry data.”
MP Coleman, D Forman, H Bryant, J Butler, B Rachet, C Maringe, E Tracey, M Coory, J Hatcher, CE McGahan, D Turner, L Marrett, ML Gjerstorff, TB Johannesen, J Adolfsson, M Lambe, G Lawrence, D Meechan ,EJ Morris, R Middleton, J Steward, MA Richards, the ICBP Module 1 Working Group.
DOI: 10.1016/S0140-6736(10)62231-3
Additional source: BBC News (“UK cancer survival rates lag behind other countries”, Dominic Hughes, 22 December 2010).
Written by: Catharine Paddock, PhD