Breast biopsy

Specimen:

Fine needle aspirate biopsy, needle core or open surgical biopsy.

X-ray of excised tissue may also be required to confirm complete excision of the lesion and as an aid to tissue sampling.

Method:

Fresh tissue; frozen section is not usually indicated. Flow cytometry only if lymphoma suspected.

Fixed tissue: light microscopy, immunohistochemistry, image analysis, proliferation index. 

Core biopsy should be submitted in formalin, wide local excision/mastectomy specimens should ideally be submitted fresh on ice. However, if significant delay in specimen transportation is anticipated then formalin fixation is acceptable. 

Sentinel lymph nodes should be submitted fixed.

The surgical specimen should be orientated and marked by the surgeon with a description on the surgical request form of the protocol used.

Interpretation:

Tumour type, grade, size, vascular invasion, excision margins, extent of in situ disease and receptor status are important prognostic indicators. 

Levels of oestrogen and progesterone receptors in tumour tissue assist in prediction of the response to hormonal therapy. 

HER2 expression is used to predict likely response to trastuzumab (Herceptin) treatment. 

See Human epidermal growth factor receptor 2 and Breast biopsy ER and PR receptors.

Reference:

Rosai J. Rosai and Ackerman's Surgical Pathology. 10th Ed. Edinburgh: Elsevier, 2011; Chapter 20.

RCPA Cancer Protocols. Invasive breast cancer structured reporting protocol. Sydney: Royal College of Pathologists of Australasia, 2012. www.rcpa.edu.au