US-guided breast biopsy with an automated cutting needle

The authors report their experience on the use of a biopsy gun for histological sampling in the field of breast lesions. The use of cytological sampling by (FNAB) fine needle aspiration biopsy has been preferred so far, because it has been thoutht to be simpler, less risky and reliable. Nevertheless, the cytological sampling shows a number of drawbacks such as the need for passes to get sufficient cellular material, frequent problems in diagnosing benign lesions and the decisive influence of the operator's skill. By using a biopsy gun for histological sampling these disadvantages are eliminated. In this case, in fact, the validity of the sample is not influenced by the operator's skill; fewer passes are necessary and their validity does not depend on the nature of the lesion. The personal series of cases involves 91 patients subjected to histological sampling for suspected lesions. Two different kinds of needles were used with one an 18 G diameter and a 23-mm extension of the sytlet, as well as a sampling window 17 mm; the other with the same diameter and extension of the stylet, as as a sampling window 8 mm. The first needle was used in all 91 patients, and the second only in 30. The results were not influenced by the employ of the different kinds of needles. A total of 268 samples were made and 110 lesions were discovered, 79 of which were malignant and 31 benign (fibroadenoma, fibrocystic change and epitheliosis). Three carcinomas were not found (3 false-negative) and one specimen was inadequate. The values of sensibility, specificity and diagnostic accuracy of the method were, respectively, 96.2%, 100% and 97.2%, with 3.8% false-negative due to three cases where the lesion was not centred for guidance mistake.