Aim: The aim of this study is to evaluate the performances of a new prototype handheld gamma probe in a series of patients with infiltrative breast cancer justifying sentinel lymph node (SLN) excision.
Methods and patients: SLN excision was performed on nine patients being treated for infiltrative breast cancer. After preoperative radio-isotope injection and lymphoscintigraphy, individual removal of all radioactive nodes was performed after their localisation using a novel new prototype handheld gamma intraoperative probe named CarolIReS. The activity of SLN following resection has been measured by a gamma ray counter. The mean geometrical detection efficiency of this gamma ray counter has been obtained by Monte Carlo simulation.
Results: With respect to the total number of SLNs identified by the CarolIReS probe, the detection probability was 80% for the lymphoscintigraphy. A mean number of 2.2 (1-5) SLNs per patient was detected after the complete SLN procedure. Among the removed SLNs, 19 were axillary SLN, 17 were located in the level I of Berg, two were located in the Rotter area and one was an intramammary SLN (ISLN) located in the lower inner area of the breast. The detection efficiency of the CarolIReS probe ranged from 2.1 to 100.0cpskBq(-1) referred to the activity of the SLN at the time of the surgery.
Conclusion: This study shows that the CarolIReS probe is well adapted to the SLN detection and allows an efficient identification of both axillary and intramammary lymph nodes.