Patients apply topical imiquimod cream to a target vulvar lesion 3 times weekly. Treatment continues for up to 12 weeks in the absence of disease progression or unacceptable toxicity. If the lesion is still present after completion of 12 weeks of imiquimod therapy, the patient undergoes surgical excision of the target lesion (and any other progressive lesions suspicious for evolving adenocarcinoma) at week 16.