Accuracy and feasibility of SentiMag technique for localization of non-palpable breast lesions.

Background: Non-palpable breast lesions are more frequent now than in the past due to the attention toward the mammary pathology and the screening diffusion; the marking of such lesions is very important for a successful surgery. The SentiMag System uses a magnetic marker that is inoculated transdermal in the breast through an 18-gauge needle.

Methods: Between April 1^st and June 30^th, 2018, 16 patients with non-palpable breast lesions were selected and subjected to surgery using the SentiMag System in our Unit. They were women with a mean age of 52 years (range 30-84 years). Seven of 16 (43.7%) had a borderline preoperative histological or cytological diagnosis (C3/B3), and nine (56.3%) a diagnosis of carcinoma (C5/B5). Six (37.5%) were marked on ultrasound guidance and 10 (62.5%) on a mammography stereotaxic guide.

Results: The time for the marker positioning ranged from 2 to 10 minutes. The radiological control of the surgical specimen always showed the presence of both the lesion and the marker, both centered within the specimen and intact. The pathology revealed seven benign lesions, one in-situ, and eight infiltrating carcinomas.

Conclusions: The SentiMag represents a fast and safe preoperative marking system of non-palpable breast lesions, cutting the radio exposure for personnel and patients. The marker is not displaced over time and it is rapid to place and easy to locate intraoperatively, allowing a clear dissection plane around the lesion. Thus, this reduces the amount of gland removed, improving the aesthetic result mostly in small breasts.