PURPOSE: To assess the feasibility of the coaxial core breast biopsy t
echnique performed under stereotactic and ultrasound (US) guidance in
vitro and in vivo. MATERIALS AND METHODS: Biopsies were performed in v
itro and in vivo with a coaxial technique. In vitro, the true needle-t
ip deviation was measured with a breast phantom on a stereotactic devi
ce with alteration of x and y axes. In vitro US studies were performed
to evaluate the optimal technique for harvesting sufficient material
for histologic work-up. In 205 patients, coaxial biopsy was performed
in 210 suspicious lesions under US (61 lesions) or stereotactic (patie
nt in the sitting position, n = 67; patient in the prone position, n =
82) guidance. In addition, the coaxial system was used for preoperati
ve localization. Surgery and histologic work-up were performed in all
eases. RESULTS: In vitro, the true needle-tip deviation was found to b
e less than indicated on the stereotactic device. A factor was introdu
ced to correct this error. For US guidance, angulation or rotation of
the coaxial needle within the lesion proved to be the best technique t
o increase the size of histologic specimen. Of the 210 lesions, 112 we
re benign and 98 were malignant. Agreement between biopsy results and
final postsurgical histologic analysis was found in 205 cases (98%). C
ONCLUSION: The coaxial breast biopsy technique is an accurate, simple,
and time-saving method performed under stereotactic or US guidance.