Breast Core Biopsy

Authors:  Dr Michelle Bennett*
                        A/Prof Liz Wylie*

What is a breast core biopsy?

Breast core biopsy is the optimal investigation used for obtaining definitive tissue samples from an area of previously determined abnormality in the breast.

Core biopsy uses a slightly larger needle (compared with fine-needle aspiration, (FNA)) to withdraw small cylinders of tissue rather than cellular material from an abnormal area. The needle is inserted into the breast typically three to six times to obtain adequate tissue samples.1 Core biopsies are consequently moderately more invasive than FNA, but the histological specimens from a core biopsy will lead to a more definitive diagnosis, because more tissue is available to the pathologist.1

What are the generally accepted indications for a breast core biopsy?

A core biopsy is the preferred sampling method to obtain a histological result from a suspicious breast imaging-detected lesion. This is in contrast to FNA, which provides only material for cytological assessment (See InsideRadiology: Breast FNA).

Indications include:

•  Lesions that are equivocal, benign or malignant on previous FNA.
• Impalpable, very small or calcified breast lesions.

What are the prerequisites for having a breast core biopsy done?

Clinical breast examination and the appropriate imaging investigations should have been carried out before a biopsy. If a biopsy is being carried out for an impalpable abnormality, the radiologist should have the imaging provided for review before carrying out the biopsy. This makes it easier to plan whether to use ultrasound, mammography or magnetic resonance imaging to locate the abnormality requiring biopsy.

What are the absolute contraindications for a breast core biopsy?

There are no absolute contraindications.

What are the relative contraindications for a breast core biopsy?

Anticoagulation is a relative contraindication for core biopsy. If the patient is taking warfarin, arrangements are usually made by the referring doctor to ensure the clotting parameters are within an acceptable range before the core biopsy. Biopsy is considered safe if the INR is <1.6, but is also feasible without complications when the INR is <3.

Vacuum-assisted core biopsy techniques provide larger specimens for histology and therefore bleeding may be more likely. If the patient is taking anticoagulants, the referring doctor should consult with the department or radiologist carrying out the procedure to ensure that the patient’s INR is in an acceptable range.

It is safe to carry out a core biopsy on a patient taking aspirin, although there may be less bruising if the aspirin is stopped 3 days before the biopsy.

Pregnancy is a relative contraindication for stereotactic (mammography-guided) biopsy, which would only be carried out in exceptional circumstances.

Morbid obesity: Prone tables used for stereotactic biopsies have a weight limit, usually approximately 150 kg. This limit varies according to the manufacturer. There is no weight limit for an ultrasound-guided core biopsy or a core biopsy on an upright stereotactic biopsy unit.

Lactation: If a woman is lactating, this is a relative contraindication for a core biopsy because of the very small risk of developing a milk fistula.

What are the adverse effects of a breast core biopsy?

Some bruising usually occurs at the biopsy site. On the rare occasion where there is bruising as a result of arterial bleeding, this usually settles with application of pressure to the breast.

There is a risk of infection; however, this is very uncommon.

A pneumothorax is a very rare complication, but may occur after biopsy of a lesion close to the chest wall.

Are there alternative imaging tests, interventions or surgical procedures to a breast core biopsy?

FNA is an alternative to a core biopsy, and a recommendation is usually made by the specialist carrying out the biopsy as to which method of biopsy is considered most appropriate. In brief, the advantages of FNA is that it is quick, low cost and only minimally invasive with good sensitivity and specificity. In contrast, core biopsy provides more specificity than FNA, with the additional advantage of ancillary tests and comment on the histopathological prognostic markers. This is especially true for the grey zone lesions of the breast.2

The main diagnostic alternative to percutaneous biopsy (i.e. FNA or core biopsy) is a diagnostic surgical biopsy. Percutaneous core biopsy is generally preferred because of comparatively minimal intervention with less scarring and deformity, and the ability to be carried out under local anaesthesia as an outpatient.

Although magnetic resonance imaging can further characterise breast lesions, this test does not obviate the need for biopsy of a lesion that is clinically suspicious or of concern on another imaging modality.

Further information about breast core biopsy:

Radiologists may need to place a tiny metal marker clip into the biopsied area at the end of the biopsy procedure. Marker clips will be used when an imaging-detected lesion has been totally or almost completely removed during the core biopsy process. Clipping is essential to allow accurate preoperative localisation of the lesion should surgical therapeutic or diagnostic excision be required. Marker clips may also be required when multiple lesions are present to differentiate between lesions. Post-biopsy mammography is required to demonstrate the position of the maker clip relative to the targeted lesion.

Useful websites about breast core biopsy:

Breast fine needle aspiration cytology and core biopsy: a guide for practice.

References:

1. Reynolds A. Stereotactic Breast Biopsy: A Review. Radiologic Technology May/June 2009; 80: 447–464.
2. Mitra S, Dey P. Fine-needle aspiration and core biopsy in the diagnosis of breast lesions: A comparison and review of the literature. CytoJournal 2016; 13: 18. doi: 10.4103/1742-6413.189637.

*The author has no conflict of interest with this topic.

Page last modified on 23/2/2024.