BACKGROUND: The histological resemblance between extramammary Paget disease and Bowen disease has been described since Bowen's original article was published in 1912. METHODS: We herein describe a case of vulval primary extramammary Paget disease in a 61-year-old women with the histological features of Bowen disease. RESULTS: Histological examination of a biopsy specimen showed acanthosis with full-thickness cellular atypia, focal hyperkeratosis and parakeratosis in the epidermis, and no characteristic Paget cells were observed. However, histological examination of an operative specimen revealed areas characteristic of Paget disease and Bowen disease. Overall, the areas characteristic of Bowen disease and Paget disease occupied 6% and 32% of the total operative specimen, respectively. The two areas were sharply separated. Immunohistochemical findings showed carcinoembryonic antigen to be expressed in areas containing Paget cells, but not in the areas characteristic of Bowen disease. Cytokeratin 7 (CK7) (OV-TL 12/30) and CK8 (35betaH11) were strongly expressed in both of these areas. The staining for high-molecular-weight cytokeratins was negative in both of these areas. CONCLUSIONS: Our findings indicated that primary extramammary Paget disease and squamous cell carcinoma in situ arose multifocally from a common cell in the epidermis.
BACKGROUND: The histological resemblance between extramammary Paget disease and Bowen disease has been described since Bowen's original article was published in 1912. METHODS: We herein describe a case of vulval primary extramammary Paget disease in a 61-year-old women with the histological features of Bowen disease. RESULTS: Histological examination of a biopsy specimen showed acanthosis with full-thickness cellular atypia, focal hyperkeratosis and parakeratosis in the epidermis, and no characteristic Paget cells were observed. However, histological examination of an operative specimen revealed areas characteristic of Paget disease and Bowen disease. Overall, the areas characteristic of Bowen disease and Paget disease occupied 6% and 32% of the total operative specimen, respectively. The two areas were sharply separated. Immunohistochemical findings showed carcinoembryonic antigen to be expressed in areas containing Paget cells, but not in the areas characteristic of Bowen disease. Cytokeratin 7 (CK7) (OV-TL 12/30) and CK8 (35betaH11) were strongly expressed in both of these areas. The staining for high-molecular-weight cytokeratins was negative in both of these areas. CONCLUSIONS: Our findings indicated that primary extramammary Paget disease and squamous cell carcinoma in situ arose multifocally from a common cell in the epidermis.