Extramammary Paget's disease

Extramammary Paget disease - high mag

Extramammary Paget's disease (EMPD) is a rare, slow-growing malignancy that typically affects areas of the body with apocrine glands, such as the genital, perianal, and axillary regions. It is similar in appearance and pathology to Paget's disease of the breast, but occurs outside the mammary glands.

Presentation

EMPD often presents as a red, scaly, and itchy rash that can be mistaken for benign skin conditions such as eczema or dermatitis. The affected area may also exhibit ulceration, bleeding, or a white plaque-like appearance. Due to its nonspecific symptoms, EMPD is frequently misdiagnosed, leading to delays in appropriate treatment.

Pathophysiology

The exact cause of EMPD is not well understood. It is believed to originate from the apocrine gland cells or from underlying malignancies such as adenocarcinoma. The disease can be classified into primary and secondary types. Primary EMPD arises de novo in the epidermis, while secondary EMPD is associated with an underlying malignancy.

Diagnosis

Diagnosis of EMPD is confirmed through a skin biopsy, which reveals characteristic Paget cells—large cells with abundant pale cytoplasm and prominent nuclei. Immunohistochemical staining is often used to differentiate EMPD from other skin conditions. Common markers include cytokeratin 7 (CK7), carcinoembryonic antigen (CEA), and gross cystic disease fluid protein-15 (GCDFP-15).

Treatment

Treatment options for EMPD include surgical excision, Mohs micrographic surgery, and topical therapies such as imiquimod or 5-fluorouracil. In cases where surgery is not feasible, radiation therapy or systemic chemotherapy may be considered. The choice of treatment depends on the extent of the disease and the presence of any underlying malignancies.

Prognosis

The prognosis for patients with EMPD varies. Localized disease has a better prognosis, while cases associated with underlying malignancies or metastasis have a poorer outcome. Regular follow-up is essential to monitor for recurrence or the development of secondary malignancies.

Related Pages

• Paget's disease of the breast
• Eczema
• Dermatitis
• Adenocarcinoma
• Mohs micrographic surgery
• Imiquimod
• 5-fluorouracil