Paget’s Disease of the Breast
~Introduction
Paget’s disease of the breast is a rare type of breast cancer that primarily affects the nipple–areola complex. It was first described in 1874 by Sir James Paget, a British surgeon, who noticed a relationship between eczematous changes of the nipple and underlying breast malignancy. Although it appears initially as a skin condition, Paget’s disease is almost always associated with an underlying carcinoma of the breast, either ductal carcinoma in situ (DCIS) or invasive ductal carcinoma.
Paget’s disease of the breast accounts for 1–4% of all breast cancers. It commonly affects women over the age of 50, but it can also occur in men, though very rarely. Early diagnosis is often delayed because the disease mimics benign skin conditions such as eczema or dermatitis. Understanding its pathology, clinical features, diagnosis, and management is essential for improving patient outcomes.
~Definition
Paget’s disease of the breast is defined as a malignant condition characterized by the presence of Paget cells in the epidermis of the nipple, usually associated with an underlying breast carcinoma.
~Epidemiology
Accounts for 1–4% of all breast cancers
More common in women, but can occur in men
Usually affects individuals aged 50–70 years
Rare in younger patients
Most cases are associated with ductal carcinoma
~Etiology and Pathogenesis
The exact cause of Paget’s disease of the breast is not fully understood. However, two main theories explain its development:
1. Epidermotropic Theory (Most Accepted)
Malignant cells originate from an underlying ductal carcinoma
These cancer cells migrate through the lactiferous ducts
They spread into the epidermis of the nipple
These malignant cells are called Paget cells
This theory explains why most patients have an underlying breast tumor.
2. In Situ Transformation Theory
Cells in the epidermis of the nipple undergo malignant transformation
Occurs independently of an underlying carcinoma
This theory explains rare cases without detectable breast tumors
~Pathology
Gross Pathology
Red, scaly, crusted, or ulcerated nipple
Thickened or flattened nipple
Possible serous or bloody discharge
Underlying breast mass may or may not be palpable
Microscopic Pathology
Presence of Paget cells in the epidermis
Paget cells are:
Large
Round or oval
Pale cytoplasm
Large nuclei with prominent nucleoli
Cells are usually found singly or in small clusters
Associated with DCIS or invasive ductal carcinoma
Immunohistochemistry
Paget cells are typically:
HER2/neu positive
CK7 positive
EMA positive
Negative for melanocytic markers (helps differentiate from melanoma)
~Clinical Features
Paget’s disease often presents with nipple changes, which may be mistaken for benign skin disorders.
Early Symptoms
Itching or tingling of the nipple
Redness and scaling
Mild irritation
Burning sensation
Progressive Symptoms
Persistent eczema-like lesion
Crusting or ulceration of the nipple
Bloody or serous nipple discharge
Flattening or retraction of the nipple
Pain or tenderness
Associated Findings
Palpable breast mass (in ~50% of cases)
Axillary lymph node enlargement (if invasive cancer present)
~Differential Diagnosis
Paget’s disease must be differentiated from other nipple conditions, including:
Eczema
Contact dermatitis
Psoriasis
Nipple adenoma
Melanoma
Bowen’s disease
Failure of symptoms to respond to topical treatment should raise suspicion of Paget’s disease.
~Diagnosis
Clinical Examination
Careful inspection of nipple–areola complex
Palpation of both breasts and axillary lymph nodes
Imaging Studies
1. Mammography
May show underlying mass
May reveal microcalcifications (DCIS)
Normal mammogram does not exclude disease
2. Ultrasound
Useful in detecting underlying lesions
Helps guide biopsy
3. MRI
Highly sensitive
Useful when mammography is normal
Helps assess disease extent
Biopsy
Definitive diagnosis requires biopsy
Types:
Punch biopsy of nipple skin
Wedge biopsy
Excisional biopsy
Histological confirmation of Paget cells is diagnostic.
~Staging
Paget’s disease itself is not staged separately. Staging depends on the associated breast carcinoma, using the TNM staging system.
~Treatment
Treatment depends on:
Presence or absence of underlying carcinoma
Tumor size
Lymph node involvement
Patient preference
Surgical Management
1. Mastectomy (Traditional Treatment)
Simple or modified radical mastectomy
Includes removal of nipple–areola complex
Sentinel lymph node biopsy is performed
2. Breast-Conserving Surgery
Wide local excision of nipple–areola complex
Removal of underlying tumor
Followed by radiotherapy
Suitable for selected patients
Axillary Management
Sentinel lymph node biopsy
Axillary lymph node dissection if nodes are positive
~Adjuvant Therapy
Radiotherapy
Given after breast-conserving surgery
Reduces local recurrence
Chemotherapy
Used if invasive carcinoma is present
Depends on tumor grade and stage
Hormonal Therapy
Given if estrogen or progesterone receptor positive
Examples: Tamoxifen, Aromatase inhibitors
Targeted Therapy
HER2-positive tumors treated with Trastuzumab
~Prognosis
Prognosis depends mainly on the underlying breast cancer.
Good Prognostic Factors
No palpable mass
DCIS only
Negative lymph nodes
Poor Prognostic Factors
Invasive carcinoma
Lymph node involvement
Large tumor size
Overall survival rates are similar to those of other breast cancers when matched by stage.
~Complications
Local recurrence
Surgical complications
Lymphedema
Psychological impact
Treatment-related side effects
~Paget’s Disease in Men
Extremely rare
Often diagnosed late
Worse prognosis compared to women
Managed similarly to female patients
~Prevention and Early Detection
Awareness of persistent nipple changes
Early medical consultation
Regular breast screening
Biopsy of non-healing nipple lesions
~Conclusion
Paget’s disease of the breast is a rare but important manifestation of breast cancer. Although it presents as a skin lesion of the nipple, it is usually associated with an underlying carcinoma. Early diagnosis is challenging due to its resemblance to benign skin conditions, leading to delayed treatment in many cases. A high index of suspicion, timely biopsy, and appropriate imaging are essential for diagnosis.
Advances in breast-conserving surgery, imaging, and targeted therapies have significantly improved outcomes. Prognosis depends largely on the presence and extent of underlying malignancy. Awareness among clinicians and patients plays a crucial role in early detection and better survival.
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