Clinically identifying women with vulvar lichen sclerosus at increased risk of squamous cell carcinoma: a case-control study.

OBJECTIVE To identify clinical factors that might identify women with vulvar lichen sclerosus who are at increased risk of developing squamous cell cacinoma. STUDY DESIGN A retrospective, case-control study compared 46 women presenting between 1992 and 2000 with clinical and histologic evidence of squamous cell carcinoma of the vulva arising in a background of lichen sclerosus and 213 new referrals with vulvar lichen sclerosus during the same period. RESULTS The ages of the patients and presence of clinical hyperplasia were the only differences between the 2 groups. CONCLUSION Women presenting with vulvar cancer arising within a background of lichen sclerosus are significantly older than women presenting with lichen sclerosus. In addition, clinical evidence of squamous hyperplasia is independently associated with vulvar carcinoma. Neither the presence nor duration of symptoms nor the loss of vulvar architecture is a useful indicator of potential cancer risk.