The aims of this work were to image and analyze the needle behavior at automated core biopsy, to investigate the clinical utility of an alternative core biopsy technique using a semiautomated gun in breast and axillary lesions, and also to compare core biopsy with surgical specimens in malignant breast lesions regarding histologic features and hormone receptor expression.

In two experimental studies, using butter and silicon phantoms, respectively, the needle pass was imaged and its dynamic behavior studied. It was shown that the needle took a curved course in phantoms. It deviated to the same side as where the tip lay, and the degree of the curvature increased with increasing hardness of the phantoms. Our experimental methods can be applied for imaging of needle behavior and thereby improvement of needle configuration.

In two clinical studies, a semiautomated gun was used for large needle core biopsy of breast and axillary lesions in two series of 145 and 21 patients, respectively. The sensitivity of the method for diagnosis of malignancy was 87% (108/124), and in 37% (31/83) of cases the full length of the needle notch was filled with specimen. No injury to the neurovascular structures of the axillary area was observed. It was concluded that the semiautomated gun can be used as an alternative to the automated gun when the size and location of the lesion render use of the automatic device uncertain or dangerous, e.g., in small breast lesions or lesions located in the axilla.

In a series of 129 cases of breast cancer, comparison of core biopsy and surgical specimens showed that core biopsy provided enough information on the histologic type and grade of the lesions. Also, there was moderate to high concordance between the two methods for assessment of progesterone receptors and estrogen receptors (Spearman`s kappa 0.67 and 0.89, respectively).