This BBC article:
http://news.bbc.co.uk/2/hi/health/7510121.stm   (or here)
claims that:

"The US had the highest five-year survival rates for breast cancer at 83.9% and prostate cancer at 91.9%...  The UK had 69.7% survival for breast cancer... and 51.1% for prostate cancer."

Those numbers would seem to means that in the UK breast cancer patients are almost twice as likely to die within 5 years, and prostate cancer patients are six times as likely to die within 5 years, compared to the USA.

However, the BBC’s prostate cancer numbers require some explanation, because PSA tests are much more widely used in the USA than in the UK, which changes the meanings of some of the statistics.

I did some checking, and found better numbers for prostate cancer in the US and UK.  The bottom line is that if you contract prostate cancer in the UK you are much more likely likely to die from it than if you contract prostate cancer in the USA.  But the difference is closer to 2x rather than 6x.

Let’s compare the two countries:


United Kingdom:

UK Population (2006): 60.588 million 
UK Population (2007): 60.975 million
http://www.woodlands-junior.kent.sch.uk/customs/questions/population.html

UK population male v. female (from 2001 census):
  total: 60,270,708
  male: 29,782,086 = 49.41%
  female: 30,488,622 = 50.59%
http://en.wikipedia.org/w/index.php?title=Demography_of_the_United_Kingdom&oldid=304515305

UK Male population (2006) (calculated as 49.41% of total): 29.939 million
UK Male population (2007) (calculated as 49.41% of total): 30.130 million

UK new prostate cancer cases (2006): 35,515   
  Rate per 100,000 male population (given): 97.1
  Rate per 100,000 male population (calculated):  118.6
UK prostate cancer deaths (2007): 10,239
  Rate per 100,000 male population (given): 24.6
  Rate per 100,000 male population (calculated): 34.0
http://info.cancerresearchuk.org/cancerstats/types/prostate/


United States:

US Population (2008 est.): 304,059,724
  male: 49.3%
  female: 50.7%
http://quickfacts.census.gov/qfd/states/00000.html
US Male population (2008) (calculated as 49.3% of total): 149.901 million
= 4.98 times  the UK's 2007 male population

US new prostate cancer cases (2009 projected): 192,280
  "Age-adjusted rate" per 100,000 male population (given): 159.3
  Rate per 100,000 male population (calculated from 2008 population): 128.3
US prostate cancer deaths (2009 projected): 27,360
  Rate per 100,000 male population (calculated from 2008 population): 18.2
http://seer.cancer.gov/statfacts/html/prost.html

(Yes, I realize that conflating "2009 projected" diagnosis and mortality numbers with 2008 population numbers introduces some error, as does comparing 2008/2009 numbers in the USA with 2006/2007 numbers in the UK, but the errors are small.)


Observations: 

1. The US diagnosis rate is about 9% higher than the UK diagnosis rate, presumably because PSA tests are used much more widely in the USA.  Adjusting for that difference would reduce the BBC's reported 6:1 ratio in 5yr prostate cancer survival rates to about 5.5-to-1.

2. The wider use of PSA tests in the USA probably results in earlier diagnosis of prostate cancer, which means that "5 years from diagnosis" the disease has not progressed as far for the average US patient as for the average UK patient.  A better measure would be length of survival from date of disease onset, but that is impossible to know.

3. The US prostate cancer fatality rate is much lower than UK's, but not by nearly the BBC's reported 6:1 ratio.  With only 20% of US male population, the UK nevertheless has about 37.4% as many prostate cancer deaths as the US.  Coincidentally, that's almost exactly the same as the 1.9x ratio which the BBC reported for breast cancer, but much smaller than the 6x difference in 5 year death rates which the BBC reported for prostate cancer.

Now, prostate cancer is a disease which exclusively strikes the elderly, and I think that the UK population is somewhat older than the US population, which probably accounts for some small part of that difference, but it certainly can't account for all of it.  The bottom line is that someone who contracts prostate cancer in the UK is nearly twice as likely to die from it as someone who contracts prostate cancer in the USA.

The difference has been noted elsewhere, such as this article:
http://www.medicalnewstoday.com/articles/104261.php   (or here)
which says, in part:

"The decline in mortality from prostate cancer in the USA is striking in comparison to the UK, but we can only continue to speculate about the relative contributions of differences in detection and treatment..."

and:

"in both countries, mortality rates were at their highest in the early 1990s and were at almost the same rate. The divergence occurs after this period, as the mortality rate decrease in the USA (4.17% per year) was about four times the rate in the UK (1.17% per year). Patients aged 75 or older in the USA saw the largest and longest lasting decline in mortality rates, but rates had stopped declining in this group in the UK by the year 2000."

In other words, in the UK the elderly are hardest hit by the differences between the two countries -- which is exactly the result you should expect from British-style healthcare rationing, which results in much less aggressive treatment (especially of of slowly progressing cancers like prostate cancer) in people aged 75 and older.


It would be a mistake to use the BBC's numbers to support a claim that prostate cancer is 6x as likely to be fatal in the UK than in the US.  However, it is safe to say that both breast cancer and prostate cancer have much higher fatality rates in the UK than in the US.

 

Dave Burton

7/28/2009

http://www.burtonsys.com/email/