Paget’s Disease

ICD-11

code of breast: XH3E21: extramammary: XH70F8

Epidemiology

Rare disease. 3% of all breast cancers.

Definition

Uncommon intraepidermal adenocarcinoma, arising from intraductal carcinoma in the breast (mammary Paget’s disease) Can also arise from apocrine sweat glands or underlying carcinomas e.g. rectum, prostate (extramammary Paget’s disease).

Aetiology & Pathogenesis

Associated breast cancer is of the intraduct variety.

Signs & Symptoms

Circumscribed, erythematous, sometimes scaly, increasingly infiltrated plaque. Nipple (unilateral), axilla, groin or perianal. Caution: for chronic dermatitis involving one nipple -> rule out Paget’s disease.

Localisation

Nipple, axilla, genitalia, lower abdomen, perianal.

Dermatopathology

Large clear intraepithelial tumour cells, PAS positive.

Course

Slowly and gradually spreads.

Complications

Association with intraductal carcinoma (Paget’s disease) or adenocarcinoma (extramammary Paget’s disease).

Diagnosis

Clinical features and histology.

Differential diagnosis

Nipple dermatitis, perianal dermatitis, psoriasis.

Prevention & Therapy

Surgical excision adjusted to tumour size and underlying disease, multidisciplinary approach.

3.3.3 Paget’s Disease