Sentinel lymph nodes mapping in ovarian cancer- preliminary results from single cancer center study

Ovarian cancer is the most fatal of all gynecologic cancers. The need and role of pelvic and para-aortic lymphadenectomy in ovarian cancer patients with clinically normal nodes remains debated.

To assess the accuracy of sentinel lymph node (SLN) mapping in patients with ovarian carcinoma.

This is a single cohort quality improvement study conducted from May 1, 2020 to Dec. 31, 2022 at a single institution. Patients undergoing surgery for newly diagnosed ovarian carcinoma of all stages were eligible. All patients were injected with methylene blue into the bilateral ovarian cortex, uterine horns and infundibulopelvic ligaments by the same surgeon, SLN mapping was performed followed by an immediate back-up systematic pelvic and para-aortic lymphadenectomy. Ultrastaging was performed on all SLNs that were negative on original H&E slides. Descriptive statistics were used.

Twenty-nine patients were enrolled. The overall detection rate of SLN in ovarian cancer was 100%, sensitivity was 85.7%, false negative rate was 14.3%, and negative predictive value was 95.7%. The median number of SLNs removed per patient was 8 (range, 1-20) and the median total of lymph nodes removed was 34 (range, 6-66). SLNs were identified in the supra-mesenteric para-aortic basin in 90 (34%) and in the infra-mesenteric para-aortic basin in 86 (32.5%).

In this preliminary study with a small sample size of 29 patients, intraoperative SLN mapping using methylene blue injection demonstrated a high detection rate and promising feasibility and accuracy for identifying lymph node metastases in ovarian cancer.