Axillary lymph node surgery in breast cancer

What it is

Axillary surgery in breast cancer is one of two procedures, a sentinel lymph node biopsy or an axillary clearance, and both are described against the three surgical levels into which the pectoralis minor muscle divides the axilla.

• Level I: nodes lateral or inferior to pectoralis minor, including the lateral (scapular), central (axillary vein) and pectoral groups.
• Level II: nodes deep or posterior to pectoralis minor, including the central and interpectoral (Rotter's) groups and possibly portions of the subclavicular group.
• Level III: nodes medial and superior to pectoralis minor, including primarily the apical (subclavicular) group.

Sentinel node biopsy is the removal of the nodes which receive direct drainage from the tumour. A minimum of 2 nodes need to be removed, and these can be nodes from level I and maybe level II. Axillary node clearance is the wider procedure, and how much it removes is reported as most if not all level I, II and III nodes in one place and as levels I and II in another.