Breast biopsy methods and needles

Are there different types of breast biopsies?
Yes, biopsies can be done surgically (by an incision) or using various types of needles.

What is surgical breast biopsy?
During a surgical biopsy, a portion of the breast is removed for examination (incisional biopsy) or the entire breast mass may be removed (excisional biopsy, wide local excision or lumpectomy).

This type of biopsy is usually done in an operating room using sedation given through a vein and a local anaesthetic to numb your breast.1

What is needle breast biopsy?
Needle biopsy is a reliable method of obtaining tissue samples that can help diagnose whether a lesion in the breast is benign (non-cancerous) or malignant. A needle biopsy is less invasive than open and closed surgical biopsies, both of which involve a larger incision in the skin and local or general anesthesia.For this purpose a needle which can capture cells or tissue pieces during sampling can be used.2

What is the most common way to do breast biopsy?
Until the 1990: s surgical biopsies were used to analyse parts of breast tissue.3 Today needle biopsies are preferred whenever possible.4

The patient care advantages using needle biopsies are:5

  • Less invasive than surgery,
  • Does not deform the breast,
  • Causes minimal to no scarring on subsequent mammograms,
  • Can be performed quickly.

What determines if a biopsy should be taken?
The images from the mammography determine if a needle biopsy is needed.

How does the operator know where to insert the needle?
Biopsies can be safely performed with imaging guidance such as 

  • ultrasound, 
  • x-ray, 
  • computed tomography (CT), 
  • or magnetic resonance imaging (MRI). 

These types of imaging are used to determine exactly where to place the needle and perform the biopsy.The most commonly used image guidance is ultrasound guided visualisation. Sometimes also stereotactic biopsy may be considered.6 Stereotactic biopsy means that with the help of two mammography images taken from different angles, it is possible to calculate at what depth a lesion is located.7

Ultrasound-guided breast biopsy and different types of needles

Fine Needle Aspiration (FNA)

In an FNA biopsy, the doctor uses a very thin, hollow needle attached to a syringe to withdraw (aspirate) a small amount of tissue or fluid from a suspicious area. The biopsy sample is then checked to see if there are cancer cells in it.8

However, merely with a FNA it is almost impossible to determine whether a breast cancer is invasive or "in situ" (cells that resembles cancer but do not show signs of spreading). Neither is the information from FNA enough for deciding on appropriate medical treatment.1

Core Needle Biopsy (CNB)

The clear majority of ultrasound guided biopsies are made with a core needle. The CNB-needle consists of an inner and an outer part. The inner part has a sharp tip and a portion of the needle is gouged where the tissue sample gets caught when the outer sleeve is pushed over the inner needle.

Core needle biopsies have proven to be a good and reliable alternative to diagnostic surgery and the diagnostic accuracy of the CNB is generally high.3

One problem with core needles is the limited space for tissue and thereby an uncertainty as to whether the tissue sample is actually representative.3

Vacuum assisted biopsy (VAB)

Vacuum-assisted needle biopsy was presented in the 1990:s, to address the problems of with the core needle biopsies (CNB) (see above).

Similarly, to the CNB, the vacuum-assisted needle biopsy, VAB, uses two needle sleeves on top of each other. In the vacuum needle, however, the outer needle is hollow with a side opening and a fixed tip. The inner needle rotates and is moved in and out to draw tissue into a container. With vacuum tissue is sucked into the needle and the container attached to the needle. With a larger needle diameter, compared to CNB and FNA, the VAB yields a greater amount of tissue than a core needle. Several "suctions" can be done during the same needle insertion and thus guarantee better test results.3

The great benefit of VAB is that the amount of tissue during biopsy exceeds all other needle types. It offers the best possible histological sampling and helps to avoid unnecessary operations.9

The drawbacks with VAB are probably the increased risk of pain and bleeding both during and after the actual biopsy, but also an increased risk of bruising afterwards.9

The needle for needle biopsy catches cells or tissue pieces during the sampling.