Introduction/Background Sentinel lymph node biopsy (SLNB) is a technique to assess lymph node status in various cancers to avoid systematic lymphadenectomy and limit morbidity. However, its feasibility and accuracy in early stage epithelial ovarian cancer (EOC) is still unclear. This study aimed to evaluate the role of SLNB in EOC using a combination of radioactive tracer and blue dye.

Methodology This prospective observational study included 29 patients with suspected stage I and II EOC who underwent SLNB followed by systematic lymphadenectomy. The tracer was injected subperitoneally at the utero-ovarian and infundibulopelvic ligaments at their attachment to ovary. Sentinel lymph nodes (SLNs) were identified using a gamma probe and visual inspection for the method methylene blue. This was followed by systematic pelvic and paraaortic lymphadenectomy. SLNs were subjected to ultrastaging with immunohistochemistry using pancytokeratin AE1:AE3. Detection rate, sensitivity, specificity, positive and negative predictive values and diagnostic accuracy of SLNB was calculated.

Results SLN detection was performed using combination of tracers for 10 cases while SLN detection was performed using methylene blue alone for 19 cases. The SLN detection rate was 100% using both tracers while it was 89.5% using methylene blue alone. Detection rate was 37.9% in the para-aortic region alone, 20.7% in the pelvic region alone and 34.5% in both. There were 21 cases with malignant histology while there were 4 cases each of benign and borderline histology. In the latter only SLN localisation was done (N=8).The overall sensitivity, specificity, positive predictive value, and negative predictive value of SLNB were 100%. Ultrastaging detected isolated tumor cells (ITC) in five cases. No complications related to SLNB were observed.

Conclusion SLNB is a feasible and accurate technique to assess lymph node status in EOC using a combination of radioactive tracer and blue dye. Ultrastaging detected ITCs, however their clinical implication is yet unknown.

Disclosures None.