We evaluated p186Her2 overexpression and HER2 oncogene amplification in recurrent vulvar Paget's disease. We identified six patients with recurrent vulvar Paget's disease in our archives. The number of recurrences ranged from 1 to 11 over a time period of 1-168 months. Recurrences were evaluated immunohistochemically for p185Her2 overexpression with the HercepTest and for HER2 oncogene amplification with fluorescence in situ hybridization. p185Her2 overexpression was scored as 3 in two patients, as 2 in two patients, and as 1 in two patients. All patients with scores 2 and 3 showed HER2 oncogene amplification. Overexpression of p185Her2 and HER2 oncogene amplification appears to be common in recurrent vulvar Paget's disease.