Detection and credibility of sentinel node in vulvar cancer: a single institutional study and short review of literature

Abstract

To evaluate the detectability and credibility of sentinel lymph node (SLN) in vulvar cancer. With Tc99m-nanocolloid and methylene blue, we identified SLNs in 34 patients. In 27 cases both tracers were used, while in 7 only blue dye was used. Completion lymphadenectomy was performed in all patients. SLNs and non-SLNs were sent separately for pathologic evaluation. At least one SLN was identified in all patients. Detection rate per groin was not significantly higher in the combined versus blue dye only technique (42/50 vs. 10/14, p = 0.43). 99m-Tc was not superior to blue dye in detecting SLN (42/50 vs. 50/64, p = 0.65). Midline location of the tumor did not seem to negatively affect the procedure. Four false negatives were observed in three patients with tumors >4 cm. Negative predictive value of SLN was 100% for grade I tumors ≤ 4 cm in patients ≤ 71 years. Tc-99m does not seem to be superior to methylene blue in the detection of SLN in vulvar cancer. Patients of younger age with small, well-differentiated tumors appear to be the most suitable candidates for lymphatic mapping.