Chapter 1 - Diagnosis and Staging of Breast Cancer and Multidisciplinary Team Working
A CNB or a vacuum-assisted biopsy (VAB) is taken from the breast. The biopsy is frequently guided by ultrasonography, sometimes with mammography or magnetic resonance imaging (MRI). Sensitivity exceeds 98%. False-positive findings are rare.
The tissue material obtained with CNB and VAB usually allows detection of invasive tumour growth, histological typing of cancer and the carrying out of assays to determine tumour oestrogen receptor status, human epidermal growth factor receptor 2 (HER2) status and Ki-67 expression.
Fine needle aspiration cytology (FNAC) does not make a reliable distinction between invasive and in situ cancer. The specificity and sensitivity varies depending on the skill of the investigator. FNAC is useful in the diagnosis and treatment of breast cysts.
The axillary nodal status is considered the most important single prognostic factor, and may help in the selection of patients for adjuvant systemic treatments and radiation therapy.
Axillary ultrasonography is performed prior to starting cancer treatment. A needle biopsy is taken from the nodes suspicious of containing cancer at ultrasound.
A sentinel node biopsy is carried out when metastases are not detected at axillary ultrasound.
The sentinel node is the first node to receive lymph drainage from the tumour site in the breast. Sentinel node biopsy is currently the gold standard in nodal staging of patients without metastases at axillary ultrasound.
The sentinel nodes are usually detected following injection of a radioactive tracer and/or a blue dye at the tumour site in the breast.
Patients with axillary node metastases, detected before surgery, undergo axillary lymph node dissection (ALND). Until recently, ALND has also been the standard treatment for patients with sentinel node metastases. For this latter group, axillary radiotherapy or observation may also be an option, especially when adjuvant systemic therapy is offered.
Revision Questions
- What are the advantages of CNB when compared with FNAC?
- What methods are used for axillary nodal staging?
- What is the sentinel node?
