THE PATHOLOGY OF SUPERFICIALLY INVASIVE, THIN VULVAR SQUAMOUS-CELL CARCINOMA

Abstract

Cases (36) of vulvar squamous cell carcinoma, .ltoreq. 5 mm in thickness, were studied, and potential predictors of lymph node metastases were evaluated. Tumor thickness and depth of stroma invasion were measured. Inguinal lymph node metastases were present in 6 (17%) cases, all of which had primary neoplasms > 3 mm thick. The most superficial lesion to have lymph node metastasis was 3.2 mm thick and had 1.6 mm of stromal invasion. Nonetheless, depth of stromal invasion of < 3 mm was associated with statistically fewer lymph node metastases (7%) than that of neoplasms with .gtoreq. 3 mm stromal invasion (50%). Although lymphatic or blood capillary invasion was present in 4 (11%) cases, this feature had no statistically significant association with lymph node metastasis. There was no relationship between clinical stage, surface diameter, or histological grade of the lesion and lymph node metastasis. A significant percentage of cases had either carcinoma in situ (31%) or atypical hypertrophic dystrophy (19%) in the epithelium adjacent to the infiltrating carcinoma. Koilocytotic atypia suggestive of human papilloma virus infection was present in the adjacent epithelium in 47% of the cases. Thickness of the neoplasm apparently is a valid predictor for the presence or absence of lymph node metastasis in vulvar squamous cell carcinoma; it may be more useful than neoplastic depth of invasion in this regard.