A prospective study of sentinel lymph node detection in vulval carcinoma: is it time for a change in clinical practice?

ABSTRACT

OBJECTIVES: To determine the accuracy of sentinel lymph node (SLN) detection in vulval carcinoma and to report the reliability and safety of this procedure. METHODS/MATERIALS For a period of 6 years, we recruited women undergoing surgery for vulval carcinoma. All women had a preoperative biopsy confirming the depth of invasion greater than 1 mm. Sentinel lymph node detection was performed using the combined method (Tc-99m and methylene-blue dye). The standard management included complete inguinofemoral lymphadenectomy. When inguinofemoral lymph nodes were found grossly to be enlarged, these nodes were debulked, and the women subsequently treated with radiotherapy with or without chemotherapy. During the last 2 years of the study, a selected group of women had an SLN dissection alone. The SLNs were ultrastaged when they were negative on routine hematoxylin and eosin examination. RESULTS: Among 60 women undergoing SLN detection, SLN was detected in 59 women (98.3%) with combined method. Blue dye did not detect an SLN in 3 women resulting in a 93.3% detection rate. The median SLN count was 2 nodes (range, 1-9). Of the 60 women, 41 had inguinofemoral lymphadenectomy, 4 had only enlarged inguinofemoral nodes debulked, and 15 had the SLN only removed. The non-SLN count was 9 nodes (range, 3-17). There were no false-negative SLNs. Twenty-one women (35%) had positive nodes on final histology. Ultrastaging increased detection of metastases in 6.9% of nodes relative to routine hematoxylin and eosin examination and upstaged 12% of women. The median follow-up was 24 months (range, 2-66 months). CONCLUSIONS: Sentinel lymph node detection is safe and accurate in assessing lymph node status in women with vulval cancer undergoing staging. The combined method using Tc-99m and methylene blue dye injection for SLN detection has the best detection rate. Routine ultrastaging of negative SLN improves the detection of nodal metastases.