A case of Paget's disease of the vulva is presented which, over a period of 6 years, was characterized by local recurrences and metastases to the bone marrow. Detailed examination of multiple sections of the primary tumor and of the bone marrow biopsy specimen failed to demonstrate an underlying adenocarcinoma in any of the sites. The routine histologic staining and immunohistochemical staining demonstrated that the metastatic cells strongly correlated with cells from the vulvar lesion. Specifically, immunohistochemical staining of the specimens from the primary and metastatic sites was positive for the gross cystic disease fluid protein-15, which has been associated with extramammary Paget's disease uncomplicated by underlying malignancies. Finally, during several years of close follow-up, no other primary site of Paget's disease declared itself clinically or was found by radiographic studies or analysis of serum tumor markers.