Extramammary Paget disease

Extramammary Paget disease, abbreviated EMPD, is a skin disease. As the name suggests, there is also a Paget disease of the breast.

There is also a Paget disease of the bone - just to make things confusing. This is dealt with in the bone article and has nothing (from a pathologic perspective) to do with the Paget disease discussed in this article

General

• Usually not associated with malignancy, unlike the Paget disease of the breast - important difference.
• Classically seen in the vulva.
• May afflict penis.

Microscopic

Features:

• Epitheliod morphology (round/ovoid).
• Cells nested or single.
• Clear/pale cytoplasm key feature - may also be eosinophilic.
• Large nucleoli.

Images:

• Paget disease - low mag. (WC).
• Paget disease - high mag. (WC).

DDx

• Benign Toker cell hyperplasia.
• Malignant melanoma.
• Bowen disease.
• Eccrine carcinoma.

IHC

Panel:

• CEA +ve (-ve in Bowen's disease, -ve in Toker cells).
• CK7 +ve. (???)
  • Toker cells CK7 +ve.
• S100 -ve, HMB-45 -ve (both typically +ve in melanoma).

Additional:

• HER2/neu - usually +ve.
• CK5/6 -ve.
  • Usu. +ve in squamous cell carcinoma.

See also

• Paget disease.