Core Needle—to the Heart of the Matter

A core needle biopsy uses a really big needle (bor-
rowed from the veterinarian?) to withdraw a core
specimen of tissue. The core can be taken with
stereotactic guidance or by ultrasound guidance. A
stereotactic biopsy is usually used when the mam-
mogram shows a microcalcification cluster. The ul-
trasound guidance is usually used when a lump is
felt or seen on a mammogram. In either case, the
core biopsy gives the pathologist actual tissue, not
just a few cells as with an aspiration. Sure, you get
a local anesthetic, but the process is very exacting,
takes an hour or more, and is generally uncomfort-
able.
The stereotactic biopsy requires you to lie on your stomach with your breast hanging
through a hole in the table. What’s more, you must remain perfectly still for the du-
ration. Using computers and x-ray pictures, the radiological technologist, whose exper-
tise is using x-ray equipment, locates the spot to be
biopsied. Then the radiologist inserts the needle and
an attached suction pump withdraws the cores, usu-
ally several. A Steristrip closes the quarter-inch cut
where the needle was inserted, you’re sent home
bound up like a mummy, and a nurse reminds you to
use ice packs for the next 24 hours to limit bleeding
and/or swelling and general discomfort.