Evaluation of preoperative lymphoscintigraphy and sentinel node procedure in vulvar cancer

Objective: To assess the value of preoperative lymphoscintigraphy, and to evaluate the validity and feasibility of the sentinel node (SN) procedure in vulvar carcinoma. Study design: Retrospective clinical and histopathological review of 77 patients with invasive squamous cell carcinoma in vulva who were treated at Karolinska University Hospital Stockholm, Sweden, from 2000 to 2007. The patients underwent SN mapping preoperatively with radioactive tracer and blue dye (n = 60) or only blue dye (n = 17). The SN was removed separately followed by complete inguinofemoral lymphadenectomy. Results: The relation between SNs detected on the scintigram and those found during surgery showed good agreement using weighted kappa. The detection rate of SN was 98% for radioisotope plus blue dye, and 94% for blue dye alone. Two cases of false negative SN (false negative rate 2.7%) were found, both with large midline tumors. Conclusion: Preoperative scintigram is a valuable help to identify and localize the SNs and gives the best estimate of the accurate number but cannot determine if unilateral or bilateral groins should be explored in cases of midline tumors. Our results are in favor of using radioisotope and blue dye to identify the SNs. This study support previous reports that the method is not recommended for tumors larger than 40 mm to optimize detection of SN and minimize the false negative detection rate.