Page 24 - Oct - Dec 2023 Edition

SCREENING

By Dick Stockley

When I was working in The Surgery we were members of a CME site and most days every
doctor read a health education article. Old habits don’t die and I still do. This week I read a
report from a meta analysis study that had shocked the writer, a popular American health
education contributor: cancer screening had no effect on overall mortality.
It can’t be true. Can it? When a 50-year-old sees their family doctor in USA the first thing they
will look at is when was your last mammogram? When was your last colonoscopy? The figures
however from something like 18 separate trials were clear. Those screened were not living
longer than those that were not.
Now of course early detection of breast cancer from routine mammography, and early
detection of cervical cancer by Pap smears, and early detection of cancerous polyps on
colonoscopy saves lives from those cancers. However most of those screened don’t have
cancer. The number of lives saved might be thousands but looking at the whole population is
relatively few, and they all went on to die from something else. Those populations that were
screened did not live any longer than those who were not. The conclusion was that the family
doctor would have done more good measuring their waist circumference and asking the
50-year-old about obesity and processed food.
SO, DOES SCREENING MATTER?
After a big storm a man was on the seaside throwing stranded starfish back into the sea. His
friend said why bother there are millions of starfish, a few washed up on the beach don’t
matter. It matters to that one he said as he threw it back. For the woman with early detection
of breast cancer it matters. She might live another 20 years. Or she might die from a heart
attack after 6 months because of obesity, alcohol and lack of exercise.
To be effective screening must be easy, safe, and targeted towards those who will benefit
most. It must also be simple and cheap enough to be accessible by everyone. I remember a
debate many years ago on colonoscopy: in USA they recommended routine colonoscopy for
everyone over 40 as it was the most effective procedure for finding early cancer. The standard
UK screening for colorectal cancer was checking stool samples for fecal occult blood. I
commented that the English didn’t get an empire by pushing hosepipes up each others’
bottoms. But seriously more lives were saved from the easy simple fecal smear because most
over 50’s was happy to bring in a stool sample. Far fewer were willing to go through the hassle
of colonoscopy.
The point of the article though was priorities. Doctors were so fixated on high tech expensive
screening for cancers affecting a few percent of their patients, that they ignored the big issue:
over 30% of their patients are obese and eating their way to an early death. They might save a
handful of cancer deaths each year from prioritising screening but hundreds of them will die
early from a bad diet.

22