Superficially invasive stage IA vulvar squamous cell carcinoma-therapy and prognosis

Superficially invasive stage IA squamous vulvar cancer (VSCC) is defined as a single lesion measuring ≤2 cm with a depth of invasion of ≤1.0 mm (FIGO stage IA). This article examines the natural course and prognosis of superficially invasive VSCC.

This is a retrospective case series of 46 patients (median age 58 years) with superficially invasive stage IA VSCC receiving wide local excision between January 1996 and November 2014 in the University Medical Center Hamburg-Eppendorf.

Median tumor size was 4 mm. In 39/46 (84.8%) patients peri-tumoral high-grade intraepithelial neoplasia (HSIL) and/or lichen sclerosus (LS) of the vulva were histologically detected: 34 (74.0%) usual type high-grade vulvar intraepithelial neoplasia (uVIN, HSIL), 4 (8.7%) LS with simultaneous VIN (3 uVIN, 1 differentiated VIN (dVIN)), 1 (2.2%) with LS only. 37/46 (80.4%) patients had a R0 resection; in 2 (4.3%) a high-grade VIN was detected in the margin and in 7 (15.2%) the resection status was unknown. The mean follow-up was 58 (range 10-185) months. Four patients (8.7%) suffered from an invasive recurrence after 4, 17, 40, and 54 months, three in the vulva and one in the groin. All local recurrences occurred in women with LS in a combination with high-grade VIN (3 uVIN, 1 dVIN). Two were treated surgically again including inguino-femoral lymphadenectomy (ifLAE) (no regional lymph node metastasis histologically) as invasion depth exceeded 1 mm. The third patient refused treatment. Inguinal recurrence was treated with a bilateral ifLAE, revealing one positive lymph node, followed by adjuvant radiotherapy (groins, pelvis). None of these patients had experienced further recurrences at last follow-up.

Superficially invasive VSCC is characterized by having a very good prognosis. Sole surgical therapy is highly effective. Patients with LS might benefit additionally from intensified surveillance and adequate maintenance therapy in specialized centers.