28 October 2019

Breast imaging - Dr Lisa Sorger answers your questions

28 October 2019

Breast imaging - Dr Lisa Sorger answers your questions

With years of experience as a radiologist with specialist training in breast imaging, Dr Lisa Sorger has guided innumerable women through their breast imaging procedures. She answers the common questions women often have about diagnostic testing for breast cancer.

1. What should I do if I find a breast lump?

If you find a breast lump then you must go to your GP to have the lump examined.  Your GP should examine your breasts and will usually refer you to a radiology clinic to have the lump assessed.  In women under the age of 35 the first diagnostic test is an ultrasound.   Mammograms are not usually needed unless the ultrasound finding is concerning or if the ultrasound finding does not match up with the lump (the clinical finding).  In women over the age of 35, usually both ultrasound and mammogram should be performed.  This is because mammograms are a better test as women get older.  When pregnant or breastfeeding, an ultrasound is usually the best test.  

After you have the diagnostic tests, the radiologist will often send you back to the doctor to have the lump rechecked.   If there is still a lump that your doctor is concerned about then you should have a biopsy.  This method of assessing breast lumps is called the “triple test”. 

2. My doctor has told me I need a biopsy - what should I expect? 

A biopsy is the removal of tissue from any part of the body to examine it for disease.

Most biopsies are performed with minimal preparation. You must tell your doctor if you might be pregnant or taking blood thinners, on herbal supplements or have any allergies.  Breast biopsies will be performed either under ultrasound guidance or x-ray guidance.  If a biopsy is done under x-ray guidance it is often called a stereotactic biopsy.  

A biopsy needle is generally several centimetres long and the barrel is about as wide as a large paper clip. The needle is hollow so it can capture the tissue cells. 

There are several types of needles that may be used:

• A ‘fine needle aspiration’ uses a tiny thin needle, to catch the cells inside a breast lump.

• A ‘core biopsy’ needle is a slightly bigger needle that uses a spring to catch a tiny thin piece of tissue inside the device. The piece of tissue is less than the thickness of a matchstick and about half a cm long, at most.  Some women say that it feels like a rubber band snapping when this device is used.  

• Sometimes we use the core biopsy device under a vacuum, to take out slightly more tissue under pressure.  This is often done to look for microcalcifications under x-ray (stereotactic) guidance.  Usually several tissue samples are taken, to ensure that the pathologist can make a correct diagnosis.  

Any imaging-guided procedure will not be able to be used unless the area of abnormality can be seen. Some lesions, such as clustered calcifications on mammography are not as clearly shown with ultrasound as they are with mammography. Therefore, stereotactic biopsy using a mammogram machine is usually used in breast imaging to biopsy calcifications.   Your radiologist will use the image guidance best suited to biopsy the area in question.

Usually the nurse or sonographer will bring you into the radiology room and explain the procedure, check your history and medications.  The site of the lump will be checked, then the radiologist will be called.  The radiologist will also explain the procedure and will give you time to ask any questions.  You can ask questions at any time or even stop the procedure if you want to.  

Then the skin is cleaned, and local anaesthetic is put in with a tiny needle.  The local anaesthetic can sting when it goes in, but after that it should make the pain go away.  You will probably still feel pressure or a pulling feeling, but it should not be a sharp pain.  A very small nick is made in the skin at the site where the biopsy needle is to be inserted.  Using imaging guidance, the radiologist will insert the needle through the skin, advance it to the site of the lump and take the sample.  Several samples are taken to make sure that a diagnosis can be made.   After the sampling, the needle will be removed.

If the lesion is small or is calcification, then a tiny inert metal marker clip will be inserted to mark the site of the biopsy.  This is like an “X” marks the spot and it is used to make sure that the area of the biopsy can be found again.  This is necessary as sometimes, especially with small lesions, the look of the lesion changes after the biopsy and it may not be able to be easily found.  If the biopsy turns out to show a cancer, it is important that we are able to find this area so that it can be completely surgically removed.  The metal marker clips are made of titanium and are completely inert and safe to stay in your body.  

Once the biopsy is complete, pressure will be applied to stop any bleeding and the opening in the skin is covered with a dressing. No sutures are needed, and you will be given an ice pack to ease any bruising or soreness.   

Any procedure where the skin is penetrated carries a risk of infection. The chance of infection requiring antibiotic treatment appears to be less than one in 1,000.  You can also get bruising and redness at the site of the biopsy that may last up to a week or so.

3. I have dense breasts - what does that mean? 

The breast is made up of 4 types of tissue

• breast glandular tissue (this produces the milk when breastfeeding)

• ducts (this tissue is where the milk passes through when breastfeeding)

• fibrous tissue 

• and the fat in between.  

The amount of the different tissue types varies between women.   Women with dense breasts have a lot more breast glandular and duct tissue than the other types.  The milk producing glandular tissue is very solid compared to the other types of tissue, as it contains lots of cells.  The large amount of glandular tissue stops the energy of the x-ray or ultrasound and causes the “dense”, solid appearance, as the mammographic x-rays do not pass through the glandular tissue.  Cancers are also solid with lots of abnormal cells and can hide in amongst the glandular tissue. As a result, sometimes cancers may not be detected in women with dense breasts on mammograms.  

If you have dense breasts, then other ways of checking the breast are needed. Your doctor may recommend an ultrasound or an MRI in addition to a mammogram to increase the detection rate of breast cancer. 

There is also early evidence that having dense breasts may increase the risk of breast cancer (maybe because there is more glandular type of tissue that is at risk of developing cancerous change).  

4. What is the breast triple test? 

The triple test refers to three diagnostic methods: 

- Clinical: medical history and clinical breast examination 

- Imaging: mammography and/or ultrasound 

- Biopsy:  core biopsy and/or fine needle aspiration (FNA) cytology

The triple test is the recommended way to ensure accurate diagnosis for any breast changes.  Any abnormal result in any part of the triple test requires referral to a breast surgeon or a breast physician (that is a specialised breast GP) and further testing. 

The chance of cancer increases if more than one component of the triple test is positive. For most women who have a negative result on all three components of the triple test, further investigation is not required as the risk of cancer is less than 1%.  If the triple test is followed, then more than 99.6% of cancers will be found.  

This means, that if you have a lump and the imaging is normal but your doctor, after re-examining you is still concerned, then you should still go on to have a biopsy.  

However, if symptoms persist or there are risk factors, such as strong family history or previous personal history of breast cancer, or if you remain concerned, then a specialist opinion may be needed.

 

Further information for women: please visit canceraustralia.gov.au/breastcancer

For practitioners: https://www.insideradiology.com.au/breast-imaging/ or access the RACGP Breast Guide here.