Risk of occult inguinofemoral lymph node metastasis from squamous carcinoma of the vulva

Purpose: This study was undertaken to correlate preoperative primary tumor size and American Joint Committee on Cancer and International Federation of Gynecology and Obstetrics categories with the risk of subclinical metastases from squamous carcinoma of the vulva to inguinofemoral nodes in patients with a palpably negative groin preoperatively. Methods and Materials: Clinical notes, operative reports, and pathology reports from 1955 to 1990 were reviewed to assign retrospectively 1969 American Joint Committee on Cancer No and N-1 and 1988 International Federation of Gynecology and Obstetrics T categories. Results: Of 446 patients with primary carcinoma of the vulva, 226 had a groin without features indicative of lymph node metastasis. Occult groin node metastases were detected in 15.2%, 30.0%, 24.5%, and 0% of patients with T-1, T-2, T-3, and T-4 cancers, respectively. Subclinical node metastases were found in 7.0%, 22.2%, 26.9%, 34.1%, and 20.0% of patients with primary cancers measuring 1.0 cm or less, 1.1 to 2.0 cm, 2.1 to 3.0 cm, 3.1 to 5.0 cm, and larger than 5 cm, respectively. Conclusions: Efficacy assessment for elective groin node irradiation and quantitative description of the radiation dose-control relationship for subclinical disease should be based on estimates of the risk of subclinical disease within the target volume. This study may help to assess the effectiveness of current therapies. (C) 2003 Elsevier Inc.