Microglandular Adenosis of the Breast
Differential Diagnosis
Tubular Carcinoma | Microglandular Adenosis |
---|---|
Stellate, infiltrating | Nodular or diffuse |
Round to oval ducts with pointed ends and gaping lumens | Uniform small round ducts with small lumens |
Frequent apical snouts | No apical snouts |
Empty lumens | Eosinophilic secretion present in at least some lumens |
Larger cells, polarized to lumen | Cells smaller, flatter |
Round nuclei | Nuclei may be flat, parallel to base |
EMA positive | EMA negative |
Basement membrane absent | Basement membrane variable |
Sclerosing Adenosis | Microglandular Adenosis |
---|---|
Prominent myoepithelial cells | No myoepithelial cells |
Cellular, sclerotic stroma | Stroma collagenous or adipose |
Lobular | Haphazard |
Compressed lumens | Uniform round glands |
Apocrine Adenosis | Microglandular Adenosis |
---|---|
Myoepithelial layer present, may be hyperplastic | No myoepithelial cells |
Variable size and shape of glands | Uniform round glands |
Apocrine lumenal differentiation and in some cases squamous metaplasia present | No squamous or apocrine metaplasia |
EMA and GCDFP15 positive | EMA and GCDFP15 negative |
Microglandular Adenosis | Tubular Adenosis |
---|---|
Uniformly round lumens | Predominantly tubular |
Cytoplasm frequently clear | Cytoplasm eosinophilic |
No myoepithelial layer | Myoepithelial cells present |
Secretion eosinophilic | Secretion eosinophilic or basophilic |
Microglandular Adenosis | Tubular Adenoma |
---|---|
Poorly circumscribed pattern | Circumscribed |
Surrounds normal elements | Mass displaces normal elements |
No myoepithelial cell layer | Myoepithelial cell layer present |
Haphazardly scattered tubules | Densely packed tubules |
Abundant fibrous or fatty stroma | Scant stroma |