By the end of this section, students should be able to identify the lymph node groups associated with specific body regions and their related clinical pathologies, especially in the context of palpable vs. nonpalpable lymphadenopathy seen in infection, inflammation, or malignancy.
Lymphatic drainage patterns are clinically important for diagnosing infections, inflammatory disorders, and metastasis. Palpable lymph nodes often suggest localized infections or malignancy, while deep or nonpalpable nodes require imaging for detection.
Lymph Node Drainage Table (with Clinical Correlations)
| Lymph Node Group | Area of Body Drained | Associated Conditions / Pathologies | Palpable? |
|---|---|---|---|
| Deep cervical | Head, neck, oropharynx | URTI, infectious mononucleosis, Kawasaki disease, head & neck malignancy | ✅ Yes |
| Mediastinal | Trachea, esophagus | Pulmonary TB (unilateral hilar), sarcoidosis (bilateral), lung cancer, granulomatous disease | ❌ No |
| Axillary | Upper limb, breast, skin above umbilicus | Mastitis, breast cancer metastasis | ✅ Yes |
| Hilar | Lungs | Lung carcinoma, sarcoidosis, TB | ❌ No |
| Celiac | Liver, stomach, spleen, pancreas, upper duodenum | Gastric or pancreatic malignancies | ❌ No |
| Superior mesenteric | Lower duodenum → splenic flexure | Intestinal infections, mesenteric lymphadenitis | ❌ No |
| Inferior mesenteric | Splenic flexure → upper rectum | Colorectal cancer, IBD | ❌ No |
| Para-aortic | Kidneys, testes, ovaries, uterus fundus | Testicular/ovarian metastasis | ❌ No |
| Internal iliac | Cervix, prostate, lower rectum (above pectinate line) | Cervical cancer, prostate cancer | ❌ No |
| External iliac | Body of uterus, superior bladder | Uterine or bladder malignancies | ❌ No |
| Superficial inguinal | Skin below umbilicus (except popliteal area), perineum, scrotum, vulva, distal vagina | STIs, cellulitis (medial foot/leg) | ✅ Yes |
| Popliteal (“pop-lateral”) | Dorsolateral foot, posterior calf | Cellulitis of lateral foot/leg | ✅ Yes |
| Epitrochlear | Hand, forearm | Secondary syphilis, skin infections | ✅ Yes |
| Submandibular / Submental | Oral cavity, anterior tongue, lower lip | Oral malignancy or infection | ✅ Yes |
| Supraclavicular | Right: right thorax; Left (Virchow): thorax, abdomen, pelvis | Thoracic or abdominal malignancies (esp. gastric via Virchow’s node) | ✅ Yes |
| Periumbilical (Sister Mary Joseph node) | Abdomen, pelvis | Gastric or ovarian cancer metastasis | ✅ Yes |
Major Lymphatic Ducts
| Duct | Drains | Clinical Note |
|---|---|---|
| Right lymphatic duct | Right thorax, right upper limb, right head/neck | Drains into right subclavian–internal jugular junction |
| Thoracic duct | Entire lower body + left thorax + left upper limb | Drains into left subclavian–internal jugular junction; rupture → chylothorax |
Key Points for USMLE Step 1
- Virchow’s node (left supraclavicular): sentinel node for abdoU01.02.003 Lymphatic drainage associationsminal malignancy (esp. gastric).
- Axillary lymphadenopathy: think breast cancer metastasis.
- Epitrochlear lymphadenopathy: consider secondary syphilis.
- Mediastinal & hilar nodes: associated with TB, sarcoidosis, and lung cancer.
- Para-aortic nodes: drain gonadal organs (testes, ovaries).
- Sister Mary Joseph nodule: periumbilical metastasis from intra-abdominal cancers.
