Lumps or abnormalities in the breast are often detected by physical examination, mammography, sonography or other imaging studies. However, it is not always possible to tell from these imaging tests whether a growth is benign or cancerous.
A breast biopsy is performed to remove some cells—surgically or through a less invasive procedure involving a hollow needle—from a suspicious area in the breast and examine them under a microscope to determine a diagnosis. Image-guided needle biopsy is not designed to remove the entire lesion, but most of a very small lesion may be removed in the process of biopsy.
Image-guided biopsy is performed when the abnormal area in the breast is too small to be felt, making it difficult to locate the lesion by hand (called palpation).