Robotic Sentinel Lymph Node Technique in Apparent Early-Stage Ovarian Cancer

To demonstrate the feasibility and technical aspects of robotic sentinel lymph node (SLN) biopsy using indocyanine green (ICG) in a patient with apparent early-stage ovarian cancer, highlighting critical steps to optimize lymphatic mapping and node detection.

The procedure was performed at Hospital La Fe, a tertiary referral center with expertise in minimally invasive gynecologic oncology and robotic-assisted surgery.

A 52-year-old woman diagnosed with grade 3 endometrioid ovarian carcinoma after a previous adnexectomy, clinically staged as FIGO IA, was referred for surgical restaging, including sentinel lymph node mapping.

A single tracer, indocyanine green (ICG), was injected into the stumps of the infundibulo-pelvic and utero-ovarian ligaments to map the para-aortic and pelvic lymphatic fields, respectively [1,2,3]. Low-volume injections (0.2-0.5 mL at 1.25 mg/mL) were used at each point, subperitoneally, at a depth of less than 0.5 cm [1,3]. Near-infrared fluorescence imaging, integrated into the Da Vinci robotic system, enabled intraoperative lymphatic mapping and real-time identification of SLNs. The node was detected 30 minutes after the injection in both areas. SLNs were successfully identified in both regions, including a pelvic node on the external iliac vessels and two para-aortic nodes in the para-caval area. Key technical considerations to minimize tracer extravasation and ensure accurate node detection are highlighted, including careful needle manipulation, aspiration to avoid vascular puncture, and sealing of the injection site. The planned standard staging surgery was then completed: hysterectomy, contralateral adnexectomy, omentectomy, peritoneal citology and pelvic and para-aortic lymphadenectomy. Lymphadenectomy was performed from the obturator nerves and vessels (depth limit) until the renal vein (upper limit). SLN was confirmed at definitive pathology analysis performing ultrastaging protocol [3], without identifying metastases in this case.

This case supports the feasibility of robotic SLN biopsy in ovarian cancer using ICG. This approach may offer a less invasive alternative to systematic lymphadenectomy in these patients, if further studies are able to demonstrate SLN diagnostic accuracy compared with standard procedure. VIDEO ABSTRACT.