Mediastinal lymph nodes
Nodi lymphoidei mediastinales
Lymphatic & immuneLymphaticsThorax
- What it is
- Nodes clustered around the windpipe and its fork in the middle of the chest: right and left paratracheal chains, tracheobronchial nodes at the carina, subcarinal nodes beneath it and prevascular nodes in front of the great vessels behind the thymus. 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
- Receive lymph from the lungs (via the hilar nodes), heart, oesophagus and thymus and pass it to the bronchomediastinal trunks.
- Size
- About 20-40 nodes of 5-15 mm
- Clinical note
- Spread of lung cancer to these nodes (N2 disease) usually rules out simple surgery. Symmetrical enlargement of hilar and mediastinal nodes on a chest X-ray is the classic picture of sarcoidosis.