Extramammary Paget disease (EMPD) of the skin is a rare intraepidermal adenocarcinoma that is believed to originate from the apocrine glands. It is characterized by the presence of large, multinucleated epithelial cells that are seen histologically. It is most commonly found in the perianal and perineal areas, as well as in the genital, axillary and inguinal regions.
Diagnosis of EMPD is made by clinical examination and histopathological examination of biopsy specimens. On physical examination, EMPD lesions generally appear as red, scaly patches that may have an eczematous or crusted appearance. Histologically, EMPD is characterized by atypical cells with large, pleomorphic, multinucleated epithelial cells that are arranged in a pagetoid pattern.
EMPD must be differentiated from other skin conditions, such as psoriasis, eczema, and seborrheic dermatitis. Additionally, it must be distinguished from other types of skin cancer, such as basal cell carcinoma, squamous cell carcinoma, and melanoma.
Treatment of EMPD is generally surgical excision of the affected area, although in some cases topical chemotherapy, photodynamic therapy, and radiation therapy may be used.
The prognosis for EMPD is generally good, with most patients having a complete remission of their disease following treatment. However, the prognosis may worsen in cases of advanced or recurrent disease. Additionally, EMPD can have a higher mortality rate in older or immunocompromised patients.