embolization theory in breast cancer
Last reviewed 01/2018
The embolization theory of the spread of breast cancer proposes that the primary tumour sends emboli of cells out via two independent routes:
- lymphatically
- haematogenously to distant sites
Consequently, the removal of all regional lymphatics will not necessarily remove the risk of dissemination of breast cancer. If there is clinical nodal involvement, already there may be distant spread. This is supported by the fact that radical nodal resection has no influence on survival; however, it is good at controlling recurrence within the axilla. A corollary or this theory is that micrometastatic spread may have occurred in the absence of clinical axillary nodal involvement.
Despite the embolization theory, the extent of axillary nodal spread does seem to offer a good index of the likelihood of distant spread of tumour. Therefore, this provides support for the practice of axillary nodal sampling or clearance at the time of definitive surgery with a view to obtaining prognostic information that may guide later treatment.