Fibroadenoma
The most common benign tumor of the female breast, typically occurring in women of reproductive age (15–35 years). It is an estrogen-sensitive, biphasic tumor.
1. Key Characteristics
| Feature | Description |
|---|---|
| Composition | Biphasic: proliferation of both stromal (fibrous) and glandular (epithelial) tissue. |
| Clinical Exam | Well-circumscribed, mobile, firm, painless mass; often called a “breast mouse.” |
| Hormonal Link | Size often fluctuates with the menstrual cycle; increases during pregnancy. |
2. Exam Must-Knows
- Diagnosis: Usually confirmed via ultrasound (well-defined, hypoechoic mass) or fine-needle aspiration.
- Comparison: Unlike breast carcinoma, fibroadenomas are mobile and lack fixity to the skin or chest wall.
- Phyllodes Tumor: A potential board-exam “trap.” Similar to a fibroadenoma, but larger and characterized by leaf-like projections. More common in older women and has malignant potential.
Pathology Board Hint: For test questions, remember: Fibroadenoma = reproductive age + mobile mass. If a vignette describes a “leaf-like” histology or a rapidly growing mass in an older patient, think Phyllodes tumor, not a simple fibroadenoma.