Paget Disease of the Breast

Paget Disease of the Breast

PDB is a relatively uncommon clinical presentation of intraductal carcinoma of the breast. It occurs almost exclusively in postmenopausal women; men are rarely affected.
PDB accounts for 1% to 4% of breast cancers.
In more than half of the cases, there is no associated palpable breast mass, and mammography results are often normal.
PDB is often mistakenly diagnosed as a chronic eczematous condition.
Not infrequently, an elderly patient may be too embarrassed to mention the lesion to her family or clinician, thereby further delaying diagnosis and treatment.

Pathophysiology

PDB is an underlying intraductal carcinoma of the breast, with retrograde extension into the overlying epidermis through mammary duct epithelium.
The epidermis becomes infiltrated with characteristic Paget cells that cause thickening of the nipple and the areolar skin.

Clinical Manifestations

The PDB lesion is usually insidious and slow growing, and it is often asymptomatic.
Patients with PDB often present with a chronic unilateral eruption on the nipple, areola, or surrounding skin; less commonly, the lesion originates and remains on the nipple.
Typically, the lesion appears as a sharply marginated red plaque with an irregular border and eczema-like appearance (Fig. 31.47).
When the nipple is involved, it may become scaly, crusted, have a bloody nipple discharge, become deformed, or retracted.

Diagnosis

Punch, wedge, or excisional biopsy of the lesional skin of the nipple-areola complex, including the dermal and subcutaneous tissue for microscopic examination.

Differential Diagnosis

Atopic Dermatitis

In addition to various unusual neoplasms, atopic dermatitis of the nipples and areolae should be included in the differential diagnosis.
Atopic dermatitis often presents bilaterally (Fig. 31.48), but may present unilaterally.
Atopic dermatitis occurs in association with a personal or family history of atopy (seeChapter 13: Eczema and Related Disorders) and it should respond rapidly to topical corticosteroid therapy.