Although I have already written a blog in regards to this story, more information is becoming available almost daily. Here’s some more on the breast screening controversy:
Cancer Research UK have since published information regarding breast screening and the review that was carried out into its effectiveness. The article that is found on there website describes reasons behind the study as well as an overview of the benefits and disadvantages on the method is a nicely balanced fashion.
In order to produce a fair and balanced review of the situation, both Cancer Research UK and the Government set up a panel of independent individuals to review the pros and cons of breast screening. The panel was made up of a breast cancer patient who was experienced in representing cancer patients and experts in medical statistics, medical research and breast cancer treatment, all headed by the world renowned statistician Sir Michael Marmot. The entire list of panel members can be found on the Cancer Research website here.
- Cancers can be picked up at a very early stage. They then have the highest possibility of being treated successfully.
- Some cancers will inevitably not be treated successfully but the screening does produce a higher number of successful cases than unsuccessful.
- Possibly the most talked about con: slow growing cancer do not necessarily cause any harm to the patient if left alone.
- Breast Screening does incur an exposure to a small amount of radiation; increases your risk of cancer no matter how small the dose (3-6 people in every 10,000)
- Emotional issues; if the patient is then called back to further screening sessions and found to be clear of cancer then the anxiety they must have been through is entirely unnecessary (1 in 25 will be called back and 1 in 5 of those called back will have breast cancer)
The biggest issue being discussed is over-diagnosis. The idea of having to experience treatment for breast cancer that would have either not harmed you or needed only half of the treatment you were actually exposed to is a frightening thought. The much feared side effects of treatment would occur completely unnecessarily to the patient, something which can cause a lot of physical as was as psychological harm to the individual. Chemotherapeutic agents have always been known for their adverse effects on healthy tissue and unfortunately the grim reality is that they themselves can damage tissue so much to cause an entirely new cancer themselves. Psychological disorders such as depression or anxiety can occur to the individual as well as general distress from going through the treatments – again, something that puts fear into anyone.
What did they find?
After looking into both randomised studies (e.g. half are screened, half are not) as well as observational studies, what was found was definitely something to draw attention to.
Out of the 1,998,225 women screened in the UK between April 2009 and March 2010;
- 15,517 women were diagnosed with cancer
- 1,300 cancer deaths are prevented through screening
- 4,000 are over-diagnosed (~1 in 4)
They have made it very clear that the evidence they based their over-diagnosis figures on is quite unreliable and there isn’t much of it. The panel also came to the conclusion that breast screening should continue considering the positive effect it has on the country as a whole.
The problem with this situation is the fact that the individual has to make their own choice and this is more than likely what is causing so much controversy over the issue. This is not to say that there usually isn’t a choice but unfortunately the screening process for the moment is the best we have and, based on the figures represented in the panel’s investigation, people will be subject to over-diagnosis and unnecessary treatment. This puts the onus upon the individual to decide whether to have the screening that can result in successful treatment or be overdiagnosed as well as not being screened and risk having a shorter life than possible. It is a horrible limbo situation that people will find themselves in and is usually the kind of choice an individual will have when offered treatment for the disease rather than a standard breast screen.
On a final note, Cancer Research supplied some simplified numbers to aid with the decision to be screened or not:
“After 20 years, out of 1,000 women who have screening, 75 will be diagnosed with breast cancer and have treatment. Out of these 75 women:
- 16 will die from breast cancer
- 59 will be successfully treated and survive their breast cancer
Whereas, after 20 years, amongst 1,000 women who have not had screening, 58 will be diagnosed with breast cancer. Of these 58 women:
- 21 will die from breast cancer
- 37 will be successfully treated and survive their breast cancer
So for every 1,000 women screened there are 5 lives saved at the expense of 17 women being diagnosed and treated for a cancer that would never have caused them any problem.”
The best thing to come out of this is progress towards a more effective method of screening. As I mentioned in my previous blog, there are other methods already out there. Unfortunately these are not currently mainstream methods so people will continue to find themselves with this difficult choice for at least a little while longer.
The Cancer Research article called ‘What the Breast Screening Review Means’: http://www.cancerresearchuk.org/cancer-help/about-cancer/cancer-questions/what-the-breast-screening-review-means
Video courtesy of YouTube.