Inguinal Node Status by Ultrasound in Vulva Cancer

Abstract

Objective. The objective of this study was to determine the value of ultrasound in preoperative assessment of groin node status in vulva cancer.Materials and methods. Women with clinically uninvolved groins who were undergoing groin node dissection for vulva cancer in our department over an 18-month period were recruited into the study. A preoperative scan of each groin to be dissected was performed to identify any suspicious lymph nodes containing metastases. Suspicious nodes were defined by two sonographic criteria: short axis diameter (>8 mm) and a long axis/short axis ratio (L/S ≤ 2). Each suspicious node was sampled by ultrasound-guided fine-needle aspiration (FNA).Results. Twenty women, with an average age of 70 years, consented to the study. Seventeen had bilateral groin node dissection and three had unilateral groin node dissection. Six (16%) of the seventeen dissected groins contained metastases. Short axis had a better overall accuracy (89%) but failed to detect a singular micrometastasis. The L/S ratio identified all positive groins but had a high false-positive rate (62%) and an overall accuracy of 67%. The combination of both criteria did not improve the overall accuracy when compared with the individual criterion. FNA was not diagnostic in three, representative in two, and falsely negative in one.Conclusion. Although L/S ratio has a lower overall accuracy, it correctly identified all groins with metastases. This has a great impact on treatment and prognosis. Its high false-positive rate may be improved by more diagnostic FNA. These sonographic criteria show good potential for segregating those with groin metastases requiring surgical treatment from those with uninvolved nodes. This experience has to be expanded to prove its clinical effectiveness.