The increase of breast cancer incidence is due to mass screening programs, especially in situ forms of which microcalcifications can be an expression.

In a significant percentage of cases, the microcalcifications are associated with uncertain malignant potential forms (B3), which can exist or develop into carcinomas in situ. For a correct histological differentiation and treatment planning are necessary adequate tissue samples. The Breast Lesion Excision System (BLES, Intact medical corporation, Natick MA, USA) is the latest available biopsy tool for percutaneous removal of a single gross breast specimen. It is a radiofrequency resection procedure with needle 6 Gauge able to withdraw a single intact tissue sample and not fragmented, of 20x15 mm, containing in most cases the whole mammographic target, allowing more accurate histological assessments and a reduction of underestimation rates than to VABB devices (vacuum-assisted breast biopsy) from 7-11 Gauge of stereotactic currently in use. The cutting system used in the procedure is supplied by radio-frequency (RF) electrosurgical power, and haemostasis and clearing of the biopsy cavity is obtained by vacuum-assisted suction. The removal of an intact lesion with preserved architecture can increase the accuracy of pathologic assessment mainly in the case of pre-neoplastic lesions and low-grade in situ carcinoma. BLES has proved safe, with mostly minor complications and able to decrease the underestimation for atypical ductal hyperplasia (ADH) and ductal carcinoma in situ (DCIS). The absolute contraindications for using BLES are patients with cardiac pacemaker and other implantable electronic devices, because the radiofrequency cutting system may create some interferences with medical devices.

It’s not recommended to perform BLES in pregnant women and in patients with breast implants, and caution has to be given in patients with anticoagulation therapy and clotting disorders, as with other large needle biopsy systems. Complications of BLES include bleeding and haematomas, usually not requiring surgical intervention, and very few cases of wound infection, that resolve with antibiotic therapy. Our experience with BLES at Foundation National Institute for Cancer Research and Treatment in Milan, started in September 2010. At that time we used the BLES in patients candidate to stereotactic biopsy for individual clusters of microcalcifications extended up to 1 cm with the aim to assess the diagnostic performance of BLES in patients with small clusters of variably suspicious microcalcifications in terms of diagnostic underestimation, as well as of margins’ status and completeness of the excision, in order to possibly avoid further surgical excision in selected patients.

In 105 consecutive patients we evaluated the radical excision analyzing margins, defined as negative, positive (disease involving at least one edge) and "close" (a disease that comes to less than 1 mm from the resection margin) and the underestimation rate the BLES than VABB devices. Of the 41 malignant lesions found, 39 underwent surgery and in 19/39 cases no residual tumour was found confirm the radicalism of BLES procedure. In 32 DCIS detected at surgical specimen diagnostic underestimation BLES was 15.6% (5/32) compared to 26.5% of our previous experience with VABB on similar targets. The margins of the sample after BLES were negative in 17.1% (7/41) of the cases and in the remaining 82.9% (34/41) the margins were positive or "close". The result depends on the inherent limitations of the method and extent of DCIS that is often greater than visible microcalcifications.

Our results demonstrate the importance of a single intact tissue sample that allows to differentiate ADH and low grade DCIS, in order to program the proper therapeutic course. The BLES could be a viable alternative to VABB also for therapeutic purposes in borderline forms, as reported in literature in cases of ADH. In low-grade in-situ forms (G1-G2) with negative margins, BLES could be subjected to sufficient an active post-biopsy surveillance.

BLES is a good option for percutaneous stereotactic biopsy of suspicious microcalcifications, allowing better histological interpretation and lower underestimation than VAB systems. When assessing the BLES as therapeutic tool, able to completely remove the target lesion without the need of further excision, we have to acknowledge that BLES is significantly more handly and user-friendly than its precursors used in the 90s.

In conclusion we believe that the BLES is a viable option diagnostic and therapeutic in selected cases with a major impact on the management of non-palpable breast lesions. The BLES system proved sufficiently accurate and safe as a diagnostic tool able to substantially reduce underestimation of disease compared with traditional VAB devices. We hope that with growing experience and the availability of a bit larger probes, better results may be achieved. Larger prospective studies are needed to assess the validity of our inferences.