To screen or not to screen

Breast screening is in the news again: at the same time as we see that deaths from breast cancer have reached the lowest point for nearly 30 years we also see a report which says that some women are being treated needlessly for breast cancer and this is due to over-diagnosis – largely due to the screening programme.

Some of the facts are simple but the consequences are less so. Over-diagnosis happens when a cancer grows so slowly or it stays the same or disappears so that the patient dies of other causes. As it is not possible to distinguish between dangerous and harmless breast cancers, treatment is offered for all detected cancers.

One of these is a condition called Ductal Carcinoma in Situ (DCIS). This is what is loosely referred to a pre-cancerous condition and until the screening programme it was often not diagnosed until it had spread or produced symptoms. It is clear that there are women with DCIS which will not progress, they will not have symptoms and they will die with it rather than of it. However, there are also women (we believe around 30–50 per cent) whose DCIS will progress into invasive breast cancer and could spread beyond the breast and, if untreated, lead to death.

For me it is quite simple: we cannot identify who falls into which group. So, for me personally, it is Russian roulette - do you spin the barrel and take a chance that you will be one of the lucky ones or do you go through the misery of treatment in case you are one of the unlucky ones.

DCIS is a complex area and Breast Cancer Campaign is funding research looking trying to understand why some cases of DCIS turn into invasive breast cancer and others don’t so that we can avoid unnecessary treatment in the future.

The screening programme is not a perfect tool but it is what we have until our research gives us something better and as long as women have the information to understand the risks and benefits it should be up to them to make their choice. I have been part of the screening programme for some time and I have never missed an appointment. I was also given the opportunity to take part in a clinical trial which is testing alternative forms of screening for ovarian cancer and I am doing that and – this may be too much information - have just received my letter to take part in the bowel cancer screening programme and will be doing that as well.