Coaxial technique: Approach to breast core biopsies

PURPOSE: To assess the feasibility of the coaxial core breast biopsy technique performed under stereotactic and ultrasound (US) guidance in vitro and in vivo. MATERIALS AND METHODS: Biopsies were performed in vitro and in vivo with a coaxial technique. In vitro, the true needle-tip deviation was measured with a breast phantom on a stereotactic device 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 (patient in the sitting position, n = 67; patient in the prone position, n = 82) guidance. In addition, the coaxial system was used for preoperative localization. Surgery and histologic work-up were performed in all eases. RESULTS: In vitro, the true needle-tip deviation was found to be less than indicated on the stereotactic device. A factor was introduced to correct this error. For US guidance, angulation or rotation of the coaxial needle within the lesion proved to be the best technique to increase the size of histologic specimen. Of the 210 lesions, 112 were benign and 98 were malignant. Agreement between biopsy results and final postsurgical histologic analysis was found in 205 cases (98%). CONCLUSION: The coaxial breast biopsy technique is an accurate, simple, and time-saving method performed under stereotactic or US guidance.