Breast Biopsy Techniques

Stereotactic core biopsy:
Pt cooperation is necessary to obtain needle guided core biopsy.
Pts breast must be compressed for 20-40 minutes
Factors which will prevent the ability to achieve adequate samping are
- inability to lie prone
- chronic cough or anxiety
- BMI - tables can generally only accomodate ~300lbs
- breasts too thin

Ultrasound guided core biopsy:
alternative for lesions that can be visualized by this technique
avoids the need for breast compression
ideal for:
- lesions close to chest wall
- superficial breast lesions
- near the nipple

Correlation of radiographic findings with pathologic diagnosis is essential to avoid missed cancers.
- 23% of non-diagnostic specimens are found to be malignant
- 10-20% of pts with DCIS diagnosed by a 14G core biopsy will have foci of invasive disease at surgery

Indications for Surgical Biopsy:
- discordance between imaging findings and pathologic diagnosis
- atypical hyperplasia, ductal or lobular (risk of adjacent intraductal or invasive ca 20-50%)
- lobular carcinoma in situ (increased risk of adjacent disease)
- papillary lesions (core cannot differentiate between benign and malignant)
- phyllodes tumor (core cannot differentiate between benign and malignant)
- radial scar (cannot differentiate between fragments of radial scar and well-differentiated carcinomas)

Needle-track seeding:
- it is not necessary to resect the core biopsy needle track.
- 42% of pts <15 days after core biopsy will have needle track seeding.  However this decreases to 15% after 28 days.  This suggests that these cells are not viable and that over time they will not survive.

Complications:
- risk of hematoma and infection: 2/1000 each
- mild bruising, mild tenderness
- pneumothorax possible but extremely rare