Sentinel node mapping with indocyanine green and endoscopic near-infrared fluorescence imaging in endometrial cancer. A pilot study and review of the literature.

OBJECTIVES

Indocyanine green (ICG) with near-infrared (NIR) fluorescence imaging is a new tracer modality used for lymphatic mapping. We report our initial experience with ICG for SLN mapping in cervical and endometrial cancer using a new endoscopic fluorescence imaging system.

METHODS

We reviewed all patients who underwent primary surgery for early-stage endometrial and cervical carcinoma with SLN mapping using fluorescence imaging followed by pelvic lymphadenectomy from February to July 2014. Intracervical injection of ICG at 3 and 9 o'clock was performed in all cases. SLNs were ultrastaged on final pathology. Sensitivity and specificity values were calculated.

RESULTS

A total of 50 patients were included in the study (42 endometrial and 8 cervical cancers). The median age was 62 (24-88) and median BMI 29 (19-56). The median SLN count was 3.1 (0-7) and median lymph node count was 15 (2-37). The overall and bilateral detection rate was 96% (48/50) and 88% (44/50). Positive SLNs were identified in 22% of patients (11/50), including 8 isolated tumor cells (ITC), 2 micrometastasis and 1 macrometastasis. There was one side-specific false negative case. Sensitivity, specificity and NPV were 93.3%, 100% and 98.7% respectively per side. Paraaortic node dissection was performed in 22% of cases. Two had paraaortic node metastasis both in patients with positive pelvic SLN. There were no allergic reactions to the ICG.

CONCLUSIONS

Based on our pilot experience, NIR fluorescence imaging with ICG is an excellent and safe tracer modality for SLN mapping with a very high overall (96%) and bilateral (88%) detection rate.