• endometrial cancer
• fluorescence imaging
• indocyanine green (ICG)
• robotic surgery
• sentinel lymph node mapping
• ultrastaging

OBJECTIVES Indocyanine green (ICG) with near-infrared (NIR) fluorescence imaging represents a new and promising tracer modality used for sentinel lymph node (SLN) mapping. This report outlines our initial experience using ICG for SLN mapping in a minimally invasive robotic-assisted laparoscopic approach in women with endometrial cancer by using Da Vinci Xi NIR fluorescence imaging system.
METHODS Patients with clinical stage I endometrial cancer were recruited from December 2015 to June 2016. All patients underwent simple robotic-assisted laparoscopic hysterectomy with pelvic lymphadenectomy and SLNs mapping by the use of Da Vinci Xi NIR fluorescence imaging system for the detection of fluorescence. An intracervical injection of ICG dye at the 3 and 9 o'clock positions was performed after the induction of general anesthesia. Histological examination of SLNs was compared with the histological definitive results of pelvic lymph nodes.
RESULTS A total of 7 patients were included in the study. The median age was 63 (50-76) and median BMI 26 (23-29). The median SLN count was 2 and median lymph node count was 15 (9-24). SLNs were located primarily in the common iliac 64.3% (9/14), followed by the external iliac node basin 21.3% (3/14), internal iliac 7.2%(1/14) and presacral 7.2%(1/14). The overall and bilateral detection rate was respectably 100% (7/7) and 100% (7/7). Positive SLNs with 1 micrometastasis were identified in 14.3% of patients (1/7), and in the final histological examination a metastatic disease was detected also in the pelvic lymph nodes of the same hemi-pelvis. There were no allergic reactions to the ICG. All procedures were successfully completed without conversion to open laparotomy and no intraoperative or postoperative complications occurred.
CONCLUSIONS In our preliminary experience NIR fluorescence imaging with ICG showed a high overall and bilateral detection rate for SLNs mapping in patients with endometrial cancer. The detection rate of micrometastasis in SLNs confirms the role of the method in detection of metastasis < 2mm. Statistical analyses were performed using SPSS software. The perfect agreement (Cohen’s Kappa=1) between the histological results of SNLs and the final histological results of pelvic lymph node, demonstrates the technique’s reliability. Therefore, the results obtained are promising for the validation of the method in our surgical center, making it possible to modulate the surgery on SNLs results. They could also allow the gradual introduction of new criteria for the planning of adjuvant therapy. Finally these results are promising to gain a surgical-anatomo pathological expertise in order to collaborate with multicenter randomized trials.