Axillary lymph nodes
Nodi lymphoidei axillares
Lymphatic & immuneLymphaticsThoraxLeft and right
View left in 3D View right in 3D
- What it is
- Twenty to thirty nodes embedded in the fat of the armpit, arranged in five groups: pectoral (anterior, along the chest wall), subscapular (posterior), humeral (lateral, beside the axillary vein), central and apical, the last passing lymph to the subclavian trunk. Each node is a bean-shaped filter 5-15 mm long with a fibrous capsule, an outer cortex of B-cell follicles, a T-cell paracortex and an inner medulla. Several afferent lymphatics enter its convex surface; one or two efferents leave at the hilum.
- Function
- Drain the whole upper limb, the breast and the chest and upper back wall down to the navel.
- Size
- 20-30 nodes of 5-15 mm
- Clinical note
- About 75 % of breast lymph drains here, so a "sentinel node" biopsy of the first axillary node is used to stage breast cancer; clearing all the nodes can cause chronic swelling of the arm (lymphoedema).