A pilot study was conducted to determine whether 3-monthly groin ultrasonography could eliminate groin dissection after a negative bilateral groin ultrasound in three groups of patients: (i) Those with a unifocal stage 1B squamous cell carcinoma of up to 20 mm in diameter. (ii) Those with an ipsilateral squamous cell carcinoma of any size which extended to within 1 cm either side of the midline. These patients underwent ipsilateral inguinofemoral lymphadenectomy and ultrasonic surveillance of the contralateral groin. (iii) Patients with multifocal invasive lesions with the largest individual focus 20 mm or less in diameter. Three additional patients were added because they either refused groin dissection or were considered unfit for surgery. All ultrasonically positive nodes were confirmed histologically. Thirty-two patients were entered, and no patients were lost to follow-up. Forty-three groins were followed. With a median follow-up of 37 months, three positive nodes (9.4%) were detected. One patient died of her recurrence (3.1%), and 39 groins (90.7%) were preserved. The overall sensitivity of ultrasonic surveillance was 100% (95% CI: 44-100%), with a specificity of 97% (95% CI: 83-99%) and a negative predictive value of 100% (95% CI: 88-100%). This pilot justifies a larger study on serial ultrasonography in lieu of groin dissection in selected patients with vulvar cancer.
Keywords: groin dissection; ultrasonic surveillance; vulvar cancer.