Hi 50Something,
There are lab tests (usealy blood)which can be done that can determine our levels of oestrogen in the body High/Low ect, but these are only normally carried out for reasons such as fertility issues,
We know that high levels of oestrogen do increase our cancer risk, but even haveing a test like this wouldnt be able to predict an idviduals likelihood of breast cancer as there are also many other factors at play.
Throughout our lives our hormone levels fluctuate, like during puberty , so its normal for our levels of oestrogen to rise sometimes, for example,it plays a role in breast development when we are young, it gives us a more mature curved figure, fuller hips, pubic and underarm hair ect .
Higher levels of oestrogen are also seen in women who are extremely overweight.and often seen in women who have high blood pressure or diabetes. Oestrogen levels also rise of course during pregnancy ,
Unfortuneately as others have said earlier , it is the tumour that is hormone positive and not the person ,so i suspect it would’nt ever be possible to devise a test that could predict which of the different people that use HRT ,would be at a greater or lower risk ,
It is possible like others have said for some people to not only have a er+ cancer but also a negative cancer at the same time ,and hormone status can also change sometimes with a reocurrence too .
About 15% of breast cancers are not hormone dependent ,so it is more common to have a er+ cancer, but for those of us that are er+ anything that increases our oestrogen levels such as the Pill/HRT ect realy wouldnt be advisable as we already know we have a hormone dependant cancer.
All these things are about increased “Risk” not “Cause” so there will be people who are on HRT/pill ect who will never get BC, just as there are people with none of the known risk factors that do get BC, But cancer by its very nature is a very complex desease so most likely has many different factors at play, The Known risk factors are Obesity,Alcohol,Enviroment ect, but more importantly genetics is thought to be at the root of all cancers whether they are hereditary or not,
As of yet, there is no single known definate cause of BC “just increased risks” so with all the many different factors involved we are not yet able to predict an individuals cancer risk or occurrence.
The good news is that with the completion of the Human Genome Project they have now been able to identify all the approximately 20,000-25,000 genes in human DNA, so it will soon be possible with the new technology to allow scientists to identify the faulty genes in individuals cancer,this will then allow everyones cancer treatment to be personalised, which will be a great leap forward for all of us, and for the future cancer .
Best Wishes
Linda (was Lindiloo) x