Laparoscopic Typical and Atypical Locations of Sentinel Node Mapping with Indocyanine Green: Comparison of 2 Near-Infrared Fluorescence Systems

Abstract

Study objective: To present our minimally invasive laparoscopic approach for sentinel lymph node (SLN) mapping with indocyanine green (ICG) using 2 fluorescence systems.

Design: A step-by-step video description of the technique showing the most frequent typical and atypical location of SLNs (educational video).

Setting: Lymph node staging in apparent confined endometrial cancer.

Patients: Women underwent SLN mapping in a minimally invasive setting.

Interventions: Laparoscopic SLN mapping before comprehensive staging including simple hysterectomy, bilateral salpingo-oophorectomy, and pelvic and aortic bilateral lymphadenectomy in case of unilateral or no identification of SLNs. The PINPOINT 0 degree HD S1 SPY camera (PINPOINT Endoscopic Fluorescence Imaging System; NOVADAQ, Mississauga, ON, Canada) or the Full HD Image 1S with ICG camera (Karl Storz Endoscopy, Tuttlingen, Germany) were used for SLN detection [1,2]. The ICG powder was diluted to a final solution of 1.25 mg/mL of fluorescent dye. After the induction of general anesthesia, a total of 4 mL of the ICG solution was injected into the cervix at the 3 and 9 o'clock positions. Attention to the technical details is crucial to correctly identify SLNs that sometimes are located in atypical locations [3].

Conclusion: Both fluorescence systems are valid and applicable for SLN mapping in the case of apparent confined endometrial cancer. In our experience, the PINPOINT system seems to allow surgeons easier and faster nodal staging of the SLNs, particularly with the color-segmented fluorescence function activated, which can better discriminate between the lymphatic channels and the real SLNs [4,5].

Keywords: Indocyanine green; Laparoscopy; Real-time fluorescence; Sentinel lymph node mapping.