Paget's disease in an epidermal cyst.

Area of Science:

• Dermatopathology
• Oncology

Background:

• Paget's disease typically affects the nipple epidermis.
• Epidermal cysts can be involved in various skin conditions.

Observation:

• A rare case of Paget's disease involving both nipple epidermis and an adjacent epidermal cyst was observed.
• Immunohistochemistry was performed to analyze the infiltrating cells.

Findings:

• Infiltrating cells in both the nipple epidermis and epidermal cyst showed similarities.
• These cells were also similar to those of the underlying mammary adenocarcinoma.

Implications:

• This case highlights that epidermal cysts can be affected by widespread epidermal diseases.
• Thorough histopathological examination is crucial to avoid overlooking such conditions in epidermal cysts.