The young woman with a breast lump is a common presentation in primary care. The majority of such cases are benign in nature, with key possibilities being fibroadenomas, fibrocystic disease, ductal ectasia, intraductal papillomas, phyllodes tumors, trauma, and infection.
However, the possibility of a malignancy should never be disregarded, especially if there is a family history of breast cancer at a younger age; and the initial approach should be similar to that of any other breast lump, i.e., via the "triple test" – clinical evaluation, imaging, and pathological studies.
Here, the patient's family history is negative for breast malignancies, while examination shows the lump to be discrete, smooth, rubbery, and widely mobile. These findings favor a benign etiology. In particular, the high mobility of the lump is suggestive of a fibroadenoma.
Imaging should be the next step. Given her age, breast ultrasound is preferable. Here, this shows the lump to be oval, well-circumscribed,
with a sharp and smooth contour, and uniformly hypoechogenic. These findings are further suggestive of a fibroadenoma.
Note that breast tissue tends to be highly dense in young women. This tends to limit the usefulness of mammography. Furthermore, magnetic resonance imaging (MRI) of the breast is expensive, and in this clinical context, unlikely to yield additional information of diagnostic value.
Pathological studies are the final step. Core needle biopsy is a suitable option in this regard. This provides histological confirmation that the mass is a fibroadenoma, clinching the diagnosis. The biopsy also shows this to be a simple fibroadenoma
Since this is a simple small fibroadenoma, she can be managed via watchful waiting. However, the option to excise the lump should also be offered, and her wishes respected. Mastectomy is completely unnecessary. The is no role for hormone therapy in her management.
Fibroadenomas are the most common benign tumor of the breast. While they can occur at any age, most cases are encountered in adolescents and young women between 20-30 years of age.
Fibroadenomas arise from the the terminal duct-lobular units; and are thus composed of both epithelial and stromal elements. They are believed to be a result of aberrant breast growth – i.e., they are hyperplastic lesions rather than true neoplasms. They usually first form during menarche, as this is a time where both stromal and epithelial cells proliferate.
Fibroadenomas are stimulated by estrogen and progesterone. They can fluctuate in size throughout the menstrual cycle; they often become larger during pregnancy and lactation; and they tend to undergo atrophic changes during menopause. Malignant transformation is rare, with a reported incidence of just 0.002-0.0125%.
Genetic factors have not been linked to the development of fibroadenomas. The age of menarche, age of menopause, and use of hormonal therapy have not been implicated as risk factors either. Interestingly, increased parity and a higher body mass index (BMI) appear to be protective.
Most fibroadenomas are detected incidentally, either during breast self-examination or routine clinical examination. They present as solitary breast lumps that are non-tender, discrete, clearly defined, smooth, rubbery, and highly mobile. Between 10-25% of these women develop multiple fibroadenomas, which may present simultaneously, or be discovered over a period of several years.
As with any other breast lump, the evaluation of these patients should follow the triple test. This involves clinical evaluation, imaging, and pathological studies.
Most guidelines agree that women <30 years of age should undergo breast ultrasound, as the density of breast tissue in this age group limits the utility of mammography. Most guidelines also agree that mammography is preferable in women ≥40 years of age. In women between 30-39 years of age, different guidelines recommend either ultrasound alone; mammograpy alone; or either of these.
Both fine needle aspiration cytology (FNAC) and core needle biopsy are suitable pathological studies. Both provide sufficient information for diagnosis. However, core needle biopsy provides additional histological information, allowing for determination as to whether the fibroadenoma is simple or complex.
Histologically, a fibroadenoma is said to be "complex" if any of the following pathological features are present: epithelial calcifications, papillary apocrine metaplasia, sclerosing adenosis, or cysts >3 mm in size. Complex fibroadenomas are associated with an elevated risk for breast cancer.
A significant minority of fibroadenomas resolve spontaneously. Therefore, many authorities recommend that simple small (<2 cm in diameter) fibroadenomas be managed via watchful waiting. These patients should be followed up at regular intervals (between 6 months to 2 years).
Fibroadenomas that are >2 cm in size, which show rapid growth, which show complex histological features, or which are encountered in women ≥35 years of age should be excised. Even otherwise, excision should be performed if the patient wishes to have the lump removed.
Open surgery has been the traditional method of excision, although endoscopic lumpectomy is also performed. Cryoablation is an alternative for simple fibroadenomas.