A patient, aged 45 years, presented to the office with complaints of a rash on her breast for four months.
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Paget disease of the breast is a malignant intraepithelial adenocarcinoma that typically presents as a scaly, erythematous, sharply circumscribed patch located at the nipple-areola complex.
Patients often report a history of persistent pruritus, pain, and burning at the site of the lesion, which is generally unilateral. More advanced disease may present with nipple discharge, ulceration, and nipple retraction. Paget disease is associated with underlying in situ or invasive carcinoma of the breast more than 80% of the time.
Paget disease of the breast typically affects women between 50 and 60 years of age. Paget disease is rare, affecting less than one percent of women in the United States.
The pathogenesis of Paget disease continues to be debated. The epidermotropic theory, which is more widely accepted, proposes that Paget cells are ductal carcinoma cells that have migrated from the breast parenchyma to the skin of the nipple. This theory is bolstered by the fact that Paget disease is often accompanied by underlying ductal carcinoma that often expresses similar molecular markers as the Paget cells.
Alternatively, the in situ transformation theory postulates that the Paget cells are independent malignant cells in the nipple epidermis. The in situ theory is supported by the small number of cases in which the mammary carcinoma is not located near the nipple-areola complex or there is no accompanying parenchymal cancer.
There is often a delay in diagnosis of Paget disease of the breast due to the often non-alarming appearance of the lesion. When Paget disease is suspected, a detailed history and physical should be performed, including evaluation of risk factors for hereditary breast cancer. Diagnosis is made by performing a full-thickness punch or wedge biopsy and finding intraepithelial adenocarcinoma cells on pathology.
An underlying palpable breast mass is found in more than half of cases of Paget disease. Mammography is also indicated, as 20% of patients without a palpable breast mass have mammographic abnormalities.
The differential diagnosis includes benign conditions such as contact dermatitis and eczema as well as malignancies such as Bowen disease (squamous cell carcinoma in situ) and superficial spreading malignant melanoma. Paget disease can be differentiated by biopsy.
Treatment approaches vary and are based on the presence of underlying breast carcinoma. Mastectomy was once considered the standard of care for Paget disease of the breast; however, some patients with Paget disease are candidates for breast conserving surgery and breast irradiation. Sentinel lymph node biopsy should be performed in cases of breast carcinoma to evaluate lymphatic metastasis.
The prognosis of noninvasive Paget disease of the breast is excellent with conservative surgery. However, patients with a palpable breast mass have a five-year survival rate of 35% to 51% and those with positive lymph nodes have a ten-year survival rate of 20 to 45%.
Megan Trainor is a medical student at Baylor College of Medicine.
Adam Rees, MD, a graduate of the David Geffen School of Medicine at UCLA, practices dermatology in Los Angeles.
- Ibrahim SF, Grekin RC, Neuhaus IM. (2012). “Chapter 121. Mammary and Extramammary Paget’s Disease.” Fitzpatrick’s Dermatology in General Medicine. New York, McGraw Hill.
- Usatine RP, Smith MA, Chumley HS, Mayeaux EJ. (2013). “Chapter 94: Paget Disease of the Breast.” The Color Atlas of Family Medicine. New York, McGraw Hill.
- Sakorafas GH, Blanchard K, Sarr MG, Farley DR. Paget’s disease of the breast. Cancer Treat Rev. 2001;27(1):9-18.