Biopsy
To determine whether a growth is cancerous, a biopsy (tissue sample) is used to extract cells or tissue for further testing. Biopsies are often used in diagnosing cancer when a lump is found during a mammogram, MRI, or other screening exam.
Biopsy procedures are guided by imaging technology, such as MRI or ultrasound, and can be performed by:
- Needle – Fine needle and core needle biopsies are used to extract cells or a small core of breast tissue.
- Stereotactic – Computer and x-ray technology are used to guide a needle to a precise spot where a tissue sample can be collected.
- Open or surgical – A sample of the growth, or entire growth, can be taken by making a small incision in the skin.

