Vulval squamous cell cancer - does precursor lesion margin status affect recurrence-free survival after optimal surgical resection for early-stage disease?

Objectives: Vulval cancer accounts for around 4% of all gynaecological malignancies and most tumours ( > 90%) are of a squamous cell histotype. Most lesions arise on a background of differentiated VIN (dVIN) or lichen sclerosus (LS). Surgical treatment has undergone a paradigm shift with less radical surgery being attempted to preserve vulval structure and function, without compromising oncological outcome. Material and methods: In this single site retrospective analysis, we consider the data from a tertiary oncology unit, to assess progression-free survival based on the presence of a precursor lesion at the margin of resection.123 patients with FIGO stage 1 vulvar SCC (n = 33 1A, n = 90 1B) were included. Results: One Hundred Five patients (85%) had an associated precursor lesion (dVIN and/or LS). Within the follow-up period, 33 patients (26.8%) had invasive recurrence, of which 24 (72.7%) had surgical resection margins which were positive for a precursor lesion. In patients with an acceptable microscopically clear invasive resection margin of > 2 mm the presence of a precursor lesion at the margin conveyed a higher risk of malignant recurrence when compared to those with completely clear margins (HR = 2.42; 95% CI 1.14-5.16). Conclusions: This study adds to the available literature emphasising the clinical significance of dVIN or LS at the surgical margin of optimally resected disease. In those who have marginal involvement of a precancerous lesion, increased surveillance should be considered. Future work should explore the need for additional adjuvant therapy in this cohort.