Cervical lymph node (staging)

Cervical lymph node staging is important in a variety of tumours, especially squamous cell carcinoma refers to evaluating regional nodal metastasis from primary cancer of the head and neck.

 The following article reflects the 8th edition of the TNM nodal staging

Nodal staging issystem published by the sameAmerican Joint Committee on Cancer, which is used for staging starting January 1, 2018 ^1,2. This system applies for carcinomas (most commonly squamous cell carcinomas ofcarcinoma) of most regions of the upper aerodigestive tract of the head and neck, including those of the oral cavity,oropharynx,hypopharynx, and larynx, and unknown primary, with the exception of viral-related (EBV or HPV) cancers and mucosal melanoma.

Cervical nodal staging categorizes metastatic lymph nodes according to location, multiplicity, size measured in greatest dimension, and presence of extranodal extension (ENE). Nodal involvement can be evaluated clinically (cN) or pathologically (pN). The major difference between the two surrounds categorization of a node measuring 3 cm or less with extranodal extension. Clinically overt ENE in a node measuring 3 cm or smaller is cN3b but pathologic ENE in a similarly sized node would be pN2a, reflecting the higher bar to demonstrate clinically overt ENE.

Clinical determination of ENE requires unambiguous findings on physical examination and supporting radiological evidence; radiologic evidence is insufficient ³. These findings are skin invasion, muscular infiltration, dense tethering/fixation to adjacent structures, or neural invasion with dysfunction involving a cranial nerve, the brachial plexus, the sympathetic trunk, or the phrenic nerve.

Clinical nodal status (cN)

Clinical criteria apply for patients treated nonsurgically, without cervical lymph node dissection. Clinical evaluation synthesizes information from such sources as physical examination, imaging, and fine-needle aspiration.

• NxNX: nodes cannot be assessed
• N0: no regional nodalnode metastases
• N1: metastasis in single ipsilateral node, ≤3 cm, and no extranodal extension (ENE(−))
• N2
  • N2a: metastasis in single ipsilateral node, 3-6>3 cm and ≤6 cm, and ENE(−)
  • N2b: metastasis in multiple ipsilateral nodes, <6all ≤6 cm, and ENE(−)
  • N2c
    • : metastasis in bilateral nodal metastasesor
    • or contralateral nodal metastases <6nodes, all ≤6 cm
    , and ENE(−)
• N3
  • N3a: any nodal metastasis in a node, >6 cm, and ENE(−)
  • N3b: metastasis in a node with clinically overt ENE(+) (ENE_c)

  Size dependant

Pathologic nodal status (pN)

Pathologic criteria apply for patients treated surgically, with cervical lymph node dissection, for whom multiple whole lymph nodes are available for microscopic evaluation.

• mostNX: nodes shouldcannot be <10 mmassessed
• N0: no regional node metastases
• N1: metastasis in short-axis except:single ipsilateral node, ≤3 cm, and no extranodal extension (ENE(−))
• N2
  • submental/submandibularN2a: metastasis in single ipsilateral node, >3 cm and jugulodigastric: <15 mm≤6 cm, and ENE(−); or metastasis in single ipsilateral node, ≤3 cm, and ENE(+)
  • retropharyngealN2b: <8 mm metastasis in multiple ipsilateral nodes, all ≤6 cm, and ENE(−)
  • N2c: metastasis in bilateral or contralateral nodes, all ≤6 cm, and ENE(−)
• if usingN3
  • N3a: metastasis in a node, >6 cm, and ENE(−)
  • N3b: metastasis in single ipsilateral node, >3 cm, and ENE(+); or multiple ipsilateral, contralateral, or bilateral nodes any with ENE(+); or single contralateral node of any size criteria alone then there is a 10-20% error rateand ENE(+)

  The long-to-short axis ratio has also been proposed ² to help evaluate enlarged nodes in the setting of head and neck SCC. When nodes have a ratio of >2 (i.e. long and flat) 95% are benign. When the ratio <2 (i.e. rounder) then a similar proportion were malignant.

  Size independent criteria

  • loss of fatty hilum
  • focal necrosis
  • cystic necrotic nodes

  See also

  • lymph node enlargement
  • lymph node levels of the neck
  • cervical lymph node metastasis (radiologic criteria)