Lymphatic System Drainage Table
The lymphatic system is organized as a hierarchical vascular tree with region-specific drainage patterns that are anatomically predictable, though individual variation exists. 1
Major Lymphatic Regions and Their Drainage
| Lymphatic Region/Node Station | Anatomical Structures Drained | Clinical Notes |
|---|---|---|
| Superficial Inguinal Nodes | Penile skin, prepuce, shaft skin [2,3] | Crossover to contralateral nodes can occur at presymphyseal lymphatics [3] |
| Deep Inguinal Nodes (Femoral Triangle) | Glans penis, deep penile structures [2,3] | Sentinel nodes most commonly in Dassler's superomedial segment [2,3] |
| External Iliac Nodes | Bladder (primary drainage) [2] | Part of regional bladder drainage |
| Obturator Fossa Nodes | Bladder [2] | Part of regional bladder drainage |
| Internal Iliac Nodes | Bladder (extends beyond primary drainage) [2] | Drainage extends up to uretero-iliac crossing [2] |
| Common Iliac Nodes | Bladder (secondary drainage) [2] | May extend to inferior mesenteric artery level [2] |
| Paraesophageal Nodes (Station 20) | Esophagus at diaphragmatic hiatus [4] | Regional nodes for gastric tumors invading esophagus [4] |
| Lower Thoracic Paraesophageal (Station 110) | Lower thoracic esophagus [4] | Regional nodes for gastroesophageal junction tumors [4] |
| Supradiaphragmatic Nodes (Station 111) | Separate from esophagus [4] | Distant metastasis for gastric cancer unless esophageal invasion [4] |
| Posterior Mediastinal Nodes (Station 112) | Separate from esophagus and hiatus [4] | Distant metastasis for gastric cancer [4] |
| Infradiaphragmatic Nodes (Station 19) | Along subphrenic artery [4] | Part of gastric lymphatic drainage [4] |
| Hepatoduodenal Ligament (Station 12) | Along hepatic artery, portal vein, bile duct [4] | Regional gastric nodes [4] |
| Paraaortic Nodes (Stations 16a1, 16a2, 16b1, 16b2) | Variable levels from diaphragmatic hiatus to aortic bifurcation [4] | Distant metastasis for gastric cancer [4] |
| Pancreatic Head Nodes (Station 13,17) | Posterior and anterior pancreatic head [4] | Regional gastric nodes [4] |
| Superior Mesenteric Vein Nodes (Station 14v) | Along superior mesenteric vein [4] | Regional gastric nodes [4] |
| Middle Colic Nodes (Station 15) | Along middle colic vessels [4] | Distant metastasis for gastric cancer [4] |
Central Lymphatic Structures
| Structure | Function/Drainage | Clinical Significance |
|---|---|---|
| Cisterna Chyli | Collects lymph from lower body and abdomen [4] | Visualized in 1.7% of noncontrast CT scans [4] |
| Thoracic Duct | Main lymphatic trunk draining to left subclavian vein [4,5] | Visualized in 55% of CT scans [4]; injury causes chylothorax [4] |
| Right Lymphatic Duct | Drains right upper body to right subclavian vein [5] | Smaller trunk than thoracic duct [5] |
Lymphatic System Organization
The lymphatic vascular tree is organized hierarchically from peripheral to central compartments: 6
- Initial lymphatics (lymphatic capillaries): Blind-ended vessels where lymph formation occurs from interstitial fluid 5, 7
- Precollectors: Intermediate vessels connecting initial lymphatics to collecting vessels 5
- Collecting lymphatics: Segmented vessels with unidirectional valves; each segment (lymphangion) has intrinsic pumping mechanism 5, 7
- Lymph nodes: Filter lymph and house immune cells 6
- Lymphatic trunks: Large vessels (thoracic duct, right lymphatic duct) connecting to subclavian veins 5, 6
Organs with Most Active Lymphatic Drainage
The most metabolically active lymphatic drainage occurs in organs exposed to the external environment: 6
- Skin: Extensive superficial lymphatic network 6
- Gastrointestinal tract: Dense lymphatic plexus 6
- Lungs: Active afferent lymphatic system 6
Key Clinical Principles
Lymphatic drainage patterns are anatomically specific but subject to individual variation and pathologic alteration: 1
- Tumor cells enter lymphatics through lymphatic saccules and travel by embolization through afferent lymphatics 1
- Tumor cells may lodge in regional nodes or bypass nodes via alternative channels 1
- Disease, injury, or surgical treatment can alter normal drainage pathways 1
- Efferent lymphatics from nodes coalesce into collecting ducts with many alternative smaller venous communications 1