Groin Recurrences in Node Negative Vulvar Cancer Patients After Sole Sentinel Lymph Node Dissection

This study aimed to evaluate the recurrence rates after sole sentinel dissection in vulvar cancer and describe characteristics of groin recurrences.

All vulvar cancer cases between 2008 and 2014 were reviewed. Inclusion criteria were restricted to lymph node-negative patients, sole sentinel lymph node dissection (SLND), and tumor diameter less than 4 cm. In all patients, Tc-99m nanocolloid was used for preoperative SLN imaging. Regularly, planar lymphoscintigraphy and single-photon emission computed tomography with computed tomography were performed. Ultrastaging was routinely conducted on all negative lymph nodes.

Of 140 vulvar cancer cases, 30 node-negative patients underwent sole SLND and met inclusion criteria. Keratinizing squamous cell carcinoma was determined in final histology in 20/30 (66.7%) patients and the mainly diagnosed tumor stage was pT1b (21/30, 70%). Three perioperative complications occurred. On average, 4.6 (1-9) SLNs were dissected per patient and 2.5 (1-6) per each groin, respectively. During a median follow-up of 43.5 (4-75) months, 5/30 (16.7%; 95% confidence interval, 7.3%-33.6%) local recurrences occurred. In addition, 2/30 (6.6%; 95% confidence interval, 1.9%-21.3%) groin recurrences were identified within a period of 12 months after the primary surgery. Both patients had large (>2 cm) midline tumors. Despite surgical as well as adjuvant treatment of the recurrent disease, both patients with groin recurrences died.

Sentinel lymph node dissection is a safe and feasible alternative in early vulvar cancer. But false-negative sentinel carry a high risk of mostly fatal groin recurrences. Especially, midline tumors larger than 2 cm have to be treated with caution, because they are mostly found in cases with groin recurrences after sole SLND.