Abstract P3-03-38: Sentinel lymph node biopsy procedure: using surgical pliers eliminate radiation exposure risk
Authors: Tunon de Lara C , Rois M , Caron J , Herit S , Stein P , Lortal B , Cazeau AL , Godbert Y 
Published: May 2019

Introduction

The use of radioactive compounds for sentinel lymph node biopsy (SLNB) is now generally accepted for surgical treatment of breast cancer albeit the risk of radiation exposure to the surgeon. The purpose of our study was to compare the theoretical maximal radiation dose (TMRD) at the injection site of the breast versus fingers radiation dose (FRD) of the surgeon performing SLNB.

Patients, Material and Methods

This is a monocentric, prospective study on a single surgeon performing SLNB with different dosimetric measurements. Periareolar intradermal injections of technetium-99m colloidal rhenium sulphide (Nanocis® of Curium Laboratory) were administered in the nuclear medicine unit. For one and two day protocols, the activity was 25 MBq and 40 MBq ± 10%, respectively. During surgery, the nodes in the axilla were visualized with the injected blue dye and by a hand-held gamma probe. During surgery, the absorbed dose to the surgeon's right (dominant) and left hands were recorded using thermoluminescent dosimetry in a ring form From Landauer Laboratory. This lithium fluoride dosimeter enables monitoring equivalent skin dose “Hp007” with a minimum dose threshold of 0.1 mSv. On the hands, one ring was placed on each thumb under the surgical glove and another dosimeter on the nipple of the breast, covered in two thin surgical gloves. The radiation exposure to the hands of the surgeons (FRD) and injection site of the breast (TMRD) were measured by the rings' dosimeters from incision to the cutaneous stitch.

Results

Between 02-01-2018 and 04-30-2018, a total of 38 SLNBs were included in this study: 9 mastectomies, 28 lumpectomies and 1 sentinel node alone were performed by the same surgeon. The mean patient age was 57 years (range, 31-81). For one day protocol, 36 patients received 22.8 MBq (range, 15-26), and for the last two patients in the 2 day protocol, the activity was 39 and 40 MBq.

The mean exposure time was 57 min (range, 19-73) and the overall time of exposure was 33 h and 31 min. In our study, the TMRD is around 8.8 mSv for 3 months and represents approximatively 35 mSv per year for a breast surgeon. The FRD is similar between right and left hand, 0.16 and 0.15, respectively for 3 months and about 0.6 mSv per year.

Discussion

It is evident that the surgeon received the highest radiatiodose in the operating theatre, the 3 months TMRD was 8-fold higher in injection site than the FRD, 35-fold per year. Nevertheless, the maximal dose at the injection site was below the critical dose (150 mSv) recommended by the French Nuclear Safety authority (ASN). Surgical techniques using tools such as pliers significantly decrease the dose on surgeon's finger (8.8 vs 0.15mSv for 3 months). According to a French Directive, workers exposed to radiations must be monitored if the effective extremity's annual dose is likely to exceed 50 mSv. Radioactivity in operating room is systematically monitored at our institute. We encourage young surgeons to perform surgery using surgical pliers to manipulate the radioactivity injection site of in the breast, to minimize exposure to radioactivity.

Citation Format: Tunon de Lara C, Rois M, Caron J, Herit S, Stein P, Lortal B, Cazeau AL, Godbert Y. Sentinel lymph node biopsy procedure: using surgical pliers eliminate radiation exposure risk [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-03-38.