Remember Patrick Holford? Well, he’s still going. Here is the latest post on his blog. There are some interesting comments on lifetime risk of cancer and on five- and ten-year survival rates. Let’s start with Cancer Research UK though.
Five-year age-standardised net survival for all cancers combined in England and Wales has increased from 25% during 1971-1972 to a predicted survival of 49% during 2010-2011 in men […] In women, five-year survival has increased from 34% to 59% over the same time period…
Ten-year survival has followed the same trend as one- and five-year survival since the early 1970s. Ten-year age-standardised net survival for all cancers combined in England and Wales has increased from 20% during 1971-1972 to a predicted survival of 46% during 2010-2011 in men, and from 28% to 54% over the same time period in women…
The figures appear, to my untrained eyes, to be rather impressive. Particularly as the ten-year survival rate has increased so much. I note that CRUK label their data carefully (giving ICD codes, geographic area, period of time etc) and give links to further information and definitions of terms, e.g. here and here.
This rise since the 1970s is due to a combination of factors. Most important, are the decrease in all-cause mortality (i.e. increasing life expectancy); and the increase in cancer incidence. The increase in cancer incidence is due to many factors including changes in lifestyle, screening detecting more breast cancers and Prostate Specific Antigen (PSA) testing detecting more prostate cancers.
My bold. While Patrick Holford refers to lifestyle factors and earlier diagnosis in his post, he doesn’t mention increasing life expectancy as a factor in the rise.
Here’s what Patrick boldly proclaims:
Despite the billions of pounds spent on cancer research, raised by well meaning people running millions of collective miles to honour their prematurely dead relatives, things aren’t getting better. They are getting worse.
We’ve seen impressive increases in survival stats and the increase in lifetime risk is, as Patrick Holford fails to tell us, partly because we are living longer.
Holford then gives figures for lifetime risk and five-year survival rates (which he claims have increased from 49% to 54%). Unfortunately, unlike CRUK, he doesn’t tell us anything about these figures. Were the survival rates age-standardised net survival figures? If not, why not? What country or countries do these figures relate to? The hook for his blog post is an announcement about a cut in funds for an English fund but several comments in his post relate to the USA.
You can download a spreadsheet from the CRUK page on survival rates that shows the five-year figures for men, women and adults. If he is using the same data as CRUK, perhaps Holford has confused men in 2010-11 (49%) with adults in 1971-72 (30%)? He has the correct figure for adults in 2010-11 (54%) but that could be a coincidence.
He also claims that “…earlier diagnosis means more survive 5 years. If you take a look at 10 year survival rate it doesn’t look good.” Well the 10-year survival rate I’ve seen looks pretty impressive. I have no idea what data Holford is looking at to come to his conclusion.
In the final two paragraphs, the media nutritionist, pill salesman and author steers us towards diet, vitamin C… and his book about cancer. I do hope the information in his book is more clearly described than that in his blog post.