When your breast cancer cells are tested by the pathologist they will be tested to see if they have certain “receptors”. My basic non-medical understanding is that the existence of a receptor means that the cancer cells have a protein to which certain substances can attach and stimulate the cancer to grow. One of the receptors for which they test is HER2.
If your breast cancer has these proteins, you have what is called HER2 positive breast cancer (HER2+ve). The proportion of women with this diagnosis is fairly small (around 15% of breast cancer cases according to Macmillan).
Herceptin treatment (also known as Trastuzumab) is given to women with HER2 positive breast cancer. Here is my bullet point list of things to know about being HER2+ve and having Herceptin:
1. My oncologist told me NOT to google HER2+ve or Herceptin. Apparently Herceptin is a relatively new drug which is targeted to this type of cancer. Which is very good. But we don’t want to come across old information about this type of breast cancer that was written before this drug was available.
2. Herceptin is not a chemo drug. It is a “biological therapy”. This means that it targets the HER2+ve receptors on the cancer cells and destroys them that way.
3. For a year you will be given Herceptin every three weeks either by IV or a subcutaneous injection (which is an injection usually into the thigh and they alternate between the left and right thigh).
4. The injection is given slowly over the period of a few minutes. It can sting very slightly when it goes in whilst the drug is absorbed into the subcutaneous tissue of your thigh – but honestly, for me, it was completely fine and a little sting is nothing compared to everything else we have to go through. A nurse gives the injection so if it stings you can ask the nurse to slow the injection down.
5. Before you have your first Herceptin dose you have your heart checked out by having an echocardiogram. The chances are you will already have had one of these along your cancer road, but it if you haven’t then it is nothing to worry about – it is basically an ultrasound of your heart which is done by a nurse holding a sensor on your chest and looking at the image of your heart on a monitor . The reason for having your heart checked out is because there is a small chance of a side effect affecting your heart. This also means that for the year of Herceptin treatment you need to have an echocardiogram every 10 weeks.
6. The first time that you are given Herceptin you have to stay at the hospital for a few hours to be monitored for side effects. You may be given your first dose of Herceptin when you go in for one of your chemo cycles. Or your Herceptin treatment may start after your chemo treatment ends.
7. Herceptin is not like chemo in causing lots of side effects. There are some, which your oncologist will tell you about, but on the whole having the Herceptin injections is quick, painless and straightforward. I could drive myself to the hospital, have the injection, go home and carry on the day as normal. For information on the drug and possible side effects, take a look at the Breast Cancer Care website.
8. On some occasions (not all) the injection site on my leg raised up into a small lump, and then I had a red patch for a week or so. I felt no discomfort. the nurses told me that this was a common side effect and I shouldn’t worry about it. So I didn’t.
HELPFUL RESOURCES AND MORE INFORMATION
If you want to know how Herceptin works take a look at this page on the Cancer Research UK website.
The Breast Cancer Care booklet on Herceptin can be ordered or downloaded here.
For information on the drug and possible side effects, take a look at the Breast Cancer Care website.