Breast Lump in a 19-Year-Old Woman
A 19-year-old woman with a breast lump should undergo breast ultrasound as the initial and primary imaging evaluation, without mammography, unless ultrasound findings are suspicious or the clinical examination is highly concerning for malignancy. 1, 2
Initial Imaging Approach
Breast ultrasound is the first-line imaging modality for women younger than 30 years presenting with a palpable breast mass. 1, 2
Mammography is not indicated initially in this age group because most benign lesions are not visualized on mammography, breast tissue is typically dense in young women (limiting mammographic sensitivity), and there is theoretical increased radiation risk with very low breast cancer incidence (<1%) in women under 30. 1, 2, 3
The ultrasound should be a diagnostic ultrasound (not screening ultrasound) that specifically targets the palpable area with direct clinical correlation between the physical finding and imaging. 2
Management Based on Ultrasound Findings
If Ultrasound Shows Clearly Benign Features
Clinical follow-up alone is appropriate if ultrasound definitively identifies a benign entity such as a simple cyst, benign lymph node, lipoma, or hamartoma. 1, 2
No further imaging or tissue sampling is needed. 1
If Ultrasound Shows Probably Benign Features (BI-RADS 3)
Short-interval ultrasound follow-up is reasonable for palpable solid masses with benign sonographic features (oval/round shape, well-defined margins, homogeneous echogenicity, parallel orientation to chest wall, no posterior shadowing) if the clinical examination also suggests benign etiology. 1
These lesions are most commonly fibroadenomas, and the likelihood of malignancy is extremely low (0.3% in one study of women under 25 years). 1
Image-guided core biopsy may be performed instead of follow-up in specific circumstances: high-risk patients, patients awaiting organ transplant, patients with known synchronous cancers, patients trying to get pregnant, or situations where biopsy would alleviate extreme patient anxiety. 1
If Ultrasound Shows Suspicious Features (BI-RADS 4-5)
Ultrasound-guided core biopsy is warranted immediately except in rare circumstances (e.g., comorbidities contraindicating biopsy). 1
Diagnostic mammography may be appropriate before or after biopsy even in this young age group to evaluate for additional lesions, assess extent of disease, identify calcifications or architectural distortions not seen on ultrasound, and provide prebiopsy assessment if cancer is strongly suspected. 1
Core biopsy is superior to fine-needle aspiration in terms of sensitivity, specificity, correct histological grading, and allows evaluation of tumor receptor status. 1, 3
If Ultrasound is Negative but Clinical Examination is Highly Suspicious
Mammography should be performed if clinical findings remain concerning despite negative ultrasound. 1
Tissue sampling with core biopsy or surgical biopsy is warranted if both mammography and ultrasound are negative but physical examination remains highly suspicious for malignancy. 1
Physical examination findings should never be overruled by negative imaging alone. 2, 3
Critical Principles
Complete imaging workup should be performed before biopsy because biopsy-related changes (hematoma, architectural distortion) will confuse and limit subsequent image interpretation. 1, 3
Correlation between imaging and the palpable area is essential to ensure the imaged finding corresponds to the clinical concern. 1
Any highly suspicious mass detected by palpation should be biopsied, irrespective of imaging findings. 1
What NOT to Do
Do not order MRI, PET (FDG-PEM), or molecular breast imaging (Tc-99m sestamibi MBI) as these have no role in the initial evaluation of palpable breast masses in young women. 1, 2, 3
Do not proceed directly to biopsy without imaging evaluation. 3
Do not use screening ultrasound instead of diagnostic ultrasound. 2
Do not rely on mammography alone in this age group as the initial modality. 1