Outline Image Guided Percutaneous Breast Procedures Hong P. Pham, M.D. Los Angeles Kaiser Permanente Medical Center

• • • • • •

Benefits of Percutaneous biopsy technique Stereotactic guided core biopsy Ultrasound guided core biopsies Fine Needle Aspiration/Cyst Aspiration MRI guided biopsy Rad-Path Correlation

Your Role

Percutaneous Biopsy

Patient

• Large core needle biopsy – 9 G to 14 G – In past, smaller gage and open biopsy

• US / Mammography / MRI Physician

Technologist

Pathologist

– Spring loaded – Vacuum Assisted

• Modality that best depicts lesion Equipment

Advantages of Percutaneous Biopsy • • • •

No cosmetic deformity; fast recovery Minimal mammographic alteration Minimal time for biopsy and result Cost reduction of 25-50% vs surgical biopsy • Decreased physician visits • Standard of Care

Disadvantages Percutaneous Biopsy • Inadequate samples: – 2% – 6% – 9%

Cains. AJR 1994; 163:317 Dronkers. Radiology 1992; 183:631 Parker. Radiology 1990; 176:741

• Problem of the past – Small gauge and non spring loaded, non vacuum etc

• Now with larger spring loaded and vacuum assisted devices=surgical biopsy – 92-99% sensitive and 94-100% specifity

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Contraindications • Inability of the patient to cooperate for the procedure • Inability of the patient to consent for the procedure • Allergy to local anesthetic • Coagulopathies, including: – Hematologic disorders – Drug induced

• Inaccessible location

Complete diagnostic work up

Before Biopsy: Complete Work up • Diagnostic Mammogram and/or US required – Screening call back? – Palpable concern?

• BIRADS 4 or 5 • Contra-indications or difficulities? • Patient intolerance?

Lesions that should not undergo biopsy include: • BI-RADS 2: benign • Lesions better assessed with shortterm, e.g. six month, follow-up – Abscess – Mastitis – BIRADS 3

CC

ML

BI-RADS 3: Probably Benign • < 2% likelihood of malignancy – short interval (6 month) follow up / 2 yr stability – Biopsy results in a low positive predictive value for biopsy recommendation and inappropriately inflates the cost of screening.

• Needle biopsy can be useful in patients with a high anxiety level or unlikely or unable to undergo follow-up.

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BI-RADS 4: Suspicious • Percutaneous biopsy is most useful for these lesions – differentiate those requiring surgery from those which are definitely benign

• If benign and concordant with imaging – 6 mt f/u – Potential sampling error – Appropriate followup for this group after benign biopsy has been controversial. – Studies suggest poor patient compliance with a 6 month followup recommendation. Goodman. AJR 1996; 170:89

BI-RADS 5:Highly suggestive of malignancy • Percutaneous biopsy still useful – Surgical planning • Staging; lumpectomy vs mastectomy • axillary lymph node dissection

– Treatment options for chemotherapy • Receptor status

Complications • • • • • •

Very rare 0-3% Hematoma infection, Pneumothorax Vasovagal Implant rupture

Consent • • • •

Infection rare Bruising expected Bleeding rare; typically self limited Sampling error; need to still go on to surgical excision • Consent for clip

Complications • Tumor spread during biopsy? – Tumor cell displacement – Up to 1/3 show displacement on biopsy – No increased rate of recurrence after appropriate treatment • Outside of tumor environment • Host immune response • Radiation/chemotherapy

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Stereotactic Core Biopsies • • • •

Sweden 1977 stereotactic guide FNA USA first stereo unit 1986 First core needle biopsy 1990 Indications – Suspicious BIRADS 4/5 calcifications – Nonpalpable masses, Architectural distortion, Asymmetry on one view

Stereo Technique • • • • • •

Prone table; breast compression Scout; stereo pairs Localization X, Y, Z planes and transmitted Needle calibrated Skin cleansed, anesthesia, skin nick Needle advanced in front of lesion (pre-fire), fire (post-fire) • Sample, specimen radiograph • Clip and post clip stereo and mammogram

Stereo Targeting

Accurate pre-fire position

Accurate post-fire position

Errors in Targeting

Errors in Targeting

X-axis error: needle is to the right of lesion

Y-axis error: needle is inferior to lesion Left Stereo

Right Stereo

Left Stereo

Right Stereo

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Errors in Targeting

Errors in Targeting

X +Y axis error

Z-axis error: need is too proximal to lesion

Lateral view Left Stereo

Right Stereo

Left Stereo

Number of samples? • 9 gage vacuum assisted device • 8-12 samples – good to get calcs, but tissue around calcs • Concentrate on areas of concern 12

Right Stereo

Clip Placement • Typically place clip to mark most biopsies • Possibility of total removal of the lesion. • Follow up or localization for treatment

4 Lateral view

Post-clip Mammogram • After compression is released, relationship of the clip to the biopsy site can be altered. • Relationship of the clip to the biopsy site should be documented with a post-biopsy mammogram at the end of the biopsy procedure. • Was lesion sampled? • Post-biopsy changes on the mammogram are transient, often vanishing with days.

Asymmetry and Architectural Distortion • Difficult to localize – Small field of view of stereotactic window – Localizing identical site on stereo pairs may be more difficult without calcs or defining marker

• Some areas of distortion may be best visualized sonographically. • These lesions might be most accurately diagnosed with wire localization and surgical biopsy.

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Too Thin/Deep {-----Z = 20 mm-----} 23 mm needle throw

Compression = 50mm Pull back needle 5 mm prefire

• Compresses too thin (negative stroke margin) – Create big wheal of anesthesia – Aim short and fire, advance – Reverse compression paddle

• Too Close to the skin – Use half sample

Stroke Margin=[50−20]−[23−5]=12

THIN BREAST OR VERY DEEP LESION

Close to Chest Wall

Sling for Arm Through Technique Lo Rad

Reversed Paddle

Ultrasound Guided biopsy • • • • • •

Spring Loaded US Biopsy Devices

Easy, quick, lower cost No radiation Real time visualization Better patient comfort/preference Spring load vs. Vacuum Assisted Physician only vs. Physician and Sonographer

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Ultrasound guided core biopsy Technique • Physician only vs. Physician and Sonographer • Patient position key to quick and smooth procedure • Never advance needle w/o visualizing the tip • Must align transducer and needle

Entry Site: Depends on lesion depth

False impression of needle tip

Elevate deep lesions/Parallel to Chest wall

Special scenarios • Tiny lesion – Your first biopsy maybe your best shot – Leave clip

• ? Correlates with mammographic abnormality – Leave clip and check post biopsy mammogram

• Hematoma – May have to reschedule and rebiopsy

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Number of Samples??

Fine Needle Aspiration • Large core needle biopsy preferred • Axillary lesions and lymph nodes • Cyst aspiration attempted but lesion is solid • Breast too thin to accommodate core biopsy probe • Differentiation of invasive vs in situ not important, e. g. recurrence post conservation • Cytologist or cytopathologist on site

• Risk of underestimation • US-guided 14-gauge Core-Needle Breast Biopsy: Results of a Validation Study in 1352 Cases Radiology 2008 – 5.9 SAMPLES

• Personally 4-6 samples

FNA Equipment • Small gauge needle (21-25 G) • Short, rapid, stabbing motion • Vacuum generated – 10 or 20 cc syringe – Some use IV tubing to connect syringe to needle or a gun adapter – Release before needle withdrawn from lesion

Aspiration: Fluid Analysis •

Cytology analysis – If red with new blood or rusty with old blood •

6782 aspirations only 5 papillomas

– If lesion has suspicious imaging pattern, e.g. intracystic papillary lesion

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Green, gray, clear, and white fluid contents are not associated with malignancy. – Risk for false positive and atypia Ciatto Acta Cyto 1989

MRI Guided Biopsy

MRI Guided Biopsy

• Newest and increasing used • Lesion detection different than Mammo/US – Detects neovascularity – Requires IV contrast

Hands-Free mounted

• Requires cooperation of mammography and MRI technologists

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MRI guided Biopsy

MRI guided biopsy

Identification of appropriate grid box

Identification of appropriate grid box

1. Identify lesion

1. Identify lesion 2. Mark lesion

Identification of appropriate grid box 1. Identify lesion 2. Mark lesion 3. Scroll to grid image

Identification of appropriate grid box 1. 2. 3. 4.

Identify lesion Mark lesion Scroll to grid image Relate vit E to appropriate box

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The cheat sheet

MRI guided biopsy

HEAD

NIPPLE

Vit E

CHEST WALL

FEET

Rad-Pathology Correlation • Concordance: Imaging adequate explained by pathologic findings • Benign Histology – Concordant: 6 month followup • 2% false negative (cancer at biopsy site within 2 yrs)

– Non-concordant: Repeat biopsy/surgical excision • Up to 64% incidence of carcinoma when rebiopsied

Rad-Pathology Correlation • Surgical biopsy indicated – ADH, lobular neoplasia (ALH), papillary lesions, phyllodes, radial scar, mucinous lesion. – Pathologist recommendation

• Repeat needle or surgical biopsy indicated – BI-RADS 5 non-concordant lesion – Missed lesion – Pathologist recommendation

Lee Radiology 1999

Summary • Percutaneous image guided biopsy is standard of care – Safe, cost effective and widely available

• Many options and modalities available • Success requires planning and cooperation of radiologist and technologist

CASES

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Core biopsy diagnosis is ductal atypia. Patient management recommendation is: 1. Routine mammogram in one year 48 year old woman with new breast mass on mammo. How would you biopsy?

2. Six month followup

1.

Aspirate fluid

2.

FNA mass

3. Refer for high risk screening

3.

Core mass under sono guidance

4.

Core mass under stereo guidance

4. Repeat core biopsy 5. Surgical biopsy

This 7 mm cluster of pleomorphic microcalcifications was recommended for biopsy. Patient refuses surgery. How should the biopsy be performed?

Core biopsy of this lesion is reported at DCIS. Is this diagnosis concordant? 1. Yes

2. No 3. Maybe

Screening mammo detected calcifications with mammo and stereo biopsy specimen radiograph

1.

Sono guided FNA

2.

Sono guided core

3.

Stereotactic core

4.

Stereotactic core with clip placement

5.

Patient should be convinced to have surgery

screening

mammo mag

sono

Histology of core: ductal hyperplasia How do you manage this patient? 1.

Routine followup in one year

2.

Six month followup

3.

Repeat core biopsy

4.

Surgical excision

Sono guided biopsy of this new, slightly spiculated mass is reported as fibrocystic change. How do you manage this patient? 1.

Routine annual followup

2.

Six month followup

3.

Repeat core biopsy

4.

Surgical biopsy

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