Sentinel lymph node biopsy for early stage vulvar squamous cell carcinoma

Background: Patients with regional lymph node involvement from squamous cell carcinoma (SCC) of the vulva have a 48% 5-year relative survival. Recently, sentinel lymph node (SLN) biopsy has become a viable alternative to inguinofemoral lymphadenectomy. We sought to identify risk factors for predicting a positive SLN in patients with vulvar SCC.

Methods: A retrospective review of 29 patients with vulvar SCC was performed from 2016 to 2021 at a tertiary care center. Clinicopathologic data were collected in addition to SLN status, including number of lymph nodes removed.

Results: The average depth of invasion was 7.9 mm, average tumor size was 1.8 cm, 3 of 23 patients had perineural invasion, and 4 of 23 patients had lymphovascular invasion. One patient who did not map on lymphoscintigraphy and five patients with recurrent vulvar SCC were excluded from final analysis. The average number of SLNs removed was two. One patient had a positive SLN: the depth of invasion was 17 mm, tumor size was 5.1 cm, and lymphovascular invasion was present.

Conclusions: Most patients with early stage vulvar SCC had a negative SLN biopsy. Further study is needed to determine the patient subset that could avoid SLN biopsy altogether.