SEER Logo

SEER Training Modules

Lymph Node Involvement

N (Regional Lymph Nodes)

Code Description
NX Minimum requirements to assess lymph nodes cannot be met
N0 No evidence of regional node involvement
N1, N2, N3, N4 Increasing abnormality of lymph nodes (size, characteristics, location)

N Categories

  1. No Involvement / Involvement

    Absence or presence of regional lymph node metastases. Assigns N element simply by the presence of lymph node metastases, regardless of size, number, or location.

    1. Esophagus
    2. Small intestine
    3. Liver
    4. Ampulla of Vater
    5. Bone
    6. Soft tissues
    7. Skin
    8. Cervix
    9. Corpus uteri
    10. Ovary
    11. Fallopian tube
    12. Vagina
    13. Prostate
    14. Eyelid (carcinoma)
    15. Conjunctiva, uvea (melanoma)
    16. Retinoblastoma
    17. Orbit (sarcoma)
    18. Lacrimal gland
    19. Wilms' tumor
    20. Neuroblastoma
    21. Pediatric soft tissue sarcoma
  2. Size, Number, and/or Location of Involved Nodes
    1. Number and size of nodes involved. Pathologist must count the number of lymph nodes positive or measure the size of the involved node(s), or both.
      1. Colon and rectum (number only)
      2. Pancreas
      3. Testis
      4. Bladder
      5. Kidney
      6. Renal pelvis, ureter
      7. Urethra
    2. Laterality and size of nodes involved. Attending physician must identify whether the involved nodes are on the same side of the body as the primary tumor (ipsilateral) or on the opposite side (contralateral). Pathologist must measure the size of the involved node(s). Both criteria apply for some sites.
      1. Lip and oral cavity
      2. Pharynx
      3. Larynx
      4. Paranasal sinuses
      5. Salivary glands
      6. Melanoma (size and location)
      7. Breast (pN)
      8. Penis
      Laterality Only
      1. Thyroid
      2. Vagina
      3. Vulva
    3. Specific lymph node chains. N element criteria include names of specific lymph node chains as part of staging.
      1. Anal canal
      2. Gallbladder, bile ducts
      3. Lung
      4. Pleural mesothelioma
  3. Not Applicable

    The N element is not used for staging of the following sites:

    1. Brain (no scheme available in TNM)
    2. Hodgkin's disease and Non-Hodgkin's lymphoma