A core needle biopsy can also be done in several different ways:
Core needle biopsy for palpable growths: This procedure is similar to FNA for palpable growths except that that the needle used has a wider diameter and is equipped with a cutter that removes cores of tissue up to a Â½ inch long. A key advantage of this procedure is that the samples are larger than in FNA and thus enhance the possibility of making an accurate laboratory analysis.
Guided core needle biopsy for non-palpable growths: This procedure also uses a wide needle with a cutter that removes cores of tissue large enough to enhance the accuracy of laboratory analysis. However, because the growth is deep in the breast or otherwise not palpable, stereotactic imaging, ultrasound, or MRI is used to locate the growth.