Inside "Detection and Diagnosis":

@CancerQuest on Twitter:

Related to this page:

Test your knowledge on Detection and Diagnosis

Was this page helpful? | What did you like most? How can we make it better?

CancerQuest > Introduction to Patient Information > Introduction to Cancer Detection and Diagnosis > Core Needle Biopsy (CNB)

Core Needle Biopsy (CNB)

Biopsies are samples of tissue that are removed for closer examination.

Procedure
Core needle biopsy is similar to a fine needle aspiration (FNA), except that a larger (11-18 gauge) needle is used and the pathology report is different. Because the needle is larger than in a FNA, local anesthesia is used to numb the area before insertion. A small nick in the skin is made and the doctor inserts the needle through this nick. At least three, usually more, samples are taken from each breast mass to ensure an adequate sample. In most cases the doctor will use an imaging technique, such as ultrasound, to help guide the needle into the desired tissue. Steri-Strips™ are used to close the small cut and a larger bandage is placed on top to protect the wound.⁽¹⁾

Analysis
A core biopsy sample is studied differently than a FNA sample. The larger size of the sample allows the pathologist to look at the way groups of cells are organized instead of looking at individual cells. In CNB a trained pathologist looks for changes associated with a variety of diseases.⁽¹⁾ Because cancer cells are dividing in an abnormal fashion, they make the tissue around them appear disorganized. By examining collections of cells (tissue) instead of individual cells, pathologists get a good sense for the health of the organ from which the sample was removed. The study of tissues is called histology and the study of abnormal tissues is called histopathology.

Preparation and Side EffectsYou should limit alcohol consumption the day before and do not take any products containing aspirin 5 days before the procedure because alcohol and aspirin can thin the blood and result in excessive bleeding. After the procedure there may be discomfort, bruising, and bleeding. These will be short term and pain can be managed with pain medications (except aspirin). The bandages covering the wound will need to be changed and the wound cleaned.

View a table comparing Fine Needle Aspiration to Core Needle Biopsy

Go to the biopsy page to learn more and watch a documentary about biopsies, including FNA.

References for this page:

1. BD Florentine, CJ Cobb, K Rankle, T Greaves, SE Martin. Core needle biopsy. A useful adjunct to fine-needle aspiration in select patients with palpable breast lesions. Cancer Cytopathology. 1997; 81:33-39. [PUBMED]