axillary lymphatic metastasis
Last reviewed 01/2018
Axillary lymph nodes are the most important site for regional spread of breast cancer. The presence of metastasis is the single most important prognostic index of breast cancer - see submenu.
The larger the primary tumour, the greater is the risk of metastasis to axillary nodes:
- primary less than 2cm diameter - incidence of spread is 15-20%
- 2-5cm diameter - incidence 30-40%
- >5cm diameter - incidence >45%
However, there are two practical problems:
- clinical assessment of axillary nodes yields a high false positive and false negative rate
- histological identification of nodes and tumour within nodes is highly operator-dependent