Definition of Regional Lymph Nodes Flashcards
cNx
Regional lymph nodes cannot be assessed
cN0
No regional lymph node metastasis
cN1
Metastasis in a single ipsilateral lymph node, 3 cm or smaller in greatest dimension and ENE(-)
cN2
Metastasis in a single ipsilateral lymph node larger than 3 cm but not larger than 6 cm in greatest dimension and ENE(-) or metastases in multiple ipsilateral lymph nodes, none larger than 6 cm in greatest dimension and ENE(-) or in bilateral or contralateral lymph nodes, none larger than 6 cm in greatest dimension, ENE(-)
cN2a
Metastasis in single ipsilateral or contralateral node larger than 3 cm but not larger than 6 cm in greatest dimension and ENE(-)
cN2b
Metastasis in multiple ipsilateral nodes, none larger than 6 cm in greatest dimension and ENE(-)
cN2c
Metastasis in bilateral or contralateral lymph nodes, none larger than 6 cm in greatest dimension and ENE(-)
cN3
Metastasis in a lymph node larger than 6 cm in greatest dimension and ENE(-); or metastasis in a single ipsilateral node ENE(+) or multiple ipsilateral, contralateral, or bilateral nodes, any with ENE(+)
cN3a
Metastasis in a lymph node larger than 6 cm in greatest dimension and ENE(- )
cN3b
Metastasis in a single ipsilateral node ENE(+) or multiple ipsilateral, contralateral, or bilateral nodes, any with ENE(+)
pNx
Regional lymph nodes cannot be assessed
pN0
No regional lymph node metastasis
pN1
Metastasis in a single ipsilateral lymph node, 3 cm or smaller in greatest dimension and ENE(-)
pN2
Metastasis in a single ipsilateral or contra lateral ymph node, 3 cm or smaller in greatest dimension and ENE(+); or larger than 3 cm but not larger than 6 cm in greatest dimension and ENE(- ); — N2a or metastases in multiple ipsilateral lymph nodes, none larger than 6 cm in greatest dimension and ENE(-); — N2b or in bilateral or contralateral lymph nodes, none larger than 6 cm in greatest dimension, ENE(-) — N2c
pN3
Metastasis in a lymph node larger than 6 cm in greatest dimension and ENE(-) — N3a or metastasis in a single ipsilateral node larger than 3 cm in greatest dimension and ENE(+) or multiple ipsilateral, contralateral, or bilateral nodes, any with ENE(+) — N3b
Level IA boundaries
Superior: symphysis of mandible
Inferior: body of hyoid
Anterior (medial): anterior belly of contralateral digastric
Posterior (lateral): anterior belly of the ipsilateral digastric
Level IB boundaries
Superior: body of the mandible
Inferior: posterior belly of the digastric
Anterior (medial): anterior belly of the digastric
Posterior (lateral): stylohyoid m.
Level IIA boundaries
Superior: skull base
Inferior: horizontal plane defined by the inferior border of the hyoid
Anterior (medial): stylohyoid
Posterior (lateral): vertical plane defined the spinal accessory nerve
Level IIB boundaries
Superior: skull base
Inferior: horizontal plane defined by the inferior border of the hyoid bone
Anterior (medial): vertical plane defined by the spinal accessory nerve
Posterior (lateral): lateral border of the SCM
Level III boundaries
Superior: horizontal plane defined by the inferior border of the hyoid
Inferior: horizontal plane defined by the lower border of the cricoid cartilage
Anterior (medial): lateral border of SCM
Posterior (lateral): lateral border of SCM or sensory branches of the cervical plexus
Level IV boundaries
Superior: horizontal plane defined by the inferior border of the cricoid cartilage
Inferior: clavicle
Anterior (medial): lateral border of SCM
Posterior (lateral): lateral border of SCM or sensory branches of the cervical plexus
Level VA boundaries
Superior: apex of the convergence of SCM and trapezius
Inferior: horizontal plane defined by the lower border of the cricoid cartilage
Anterior (medial): posterior border of SCM or sensory branches of the cervical plexus
Posterior (lateral): anterior border of trapezius
Level VB boundaries
Superior: horizontal plane defined by the lower border of the cricoid cartilage
Inferior: clavicle
Anterior (medial): posterior border of SCM
Posterior (lateral): anterior border of trapezius
Level VI boundaries
Superior: hyoid bone
Inferior: suprasternal notch
Anterior (medial): common carotid artery
Posterior (lateral): common carotid artery
Level VII boundaries
Superior: suprasternal notch
Inferior: innominate artery
Anterior (medial): sternum
Posterior (lateral): trachea, esophagus, and prevertebral fascia
Submental lymph nodes (sublevel IA)
Lymph nodes within the triangular boundary of the anterior belly of the digastric muscles and the hyoid bone. These nodes are at greatest risk for harboring metastases from cancers arising from the floor of mouth, anterior oral tongue, anterior mandibular alveolar ridge, and lower lip.
Submandibular lymph nodes (sublevel IB)
Lymph nodes within the boundaries of the anterior and posterior bellies of the digastric muscle, the stylohyoid muscle, and the body of the mandible. These include the preglandular and the postglandular nodes and the prevascular and postvascular nodes. The submandibular gland is included in the specimen when the lymph nodes within the triangle are removed. These nodes are at greatest risk for harboring metastases from cancers arising from the oral cavity, anterior nasal cavity, skin, and soft tissue structures of the midface, as well as from the submandibular gland.
Upper jugular lymph nodes (level IIA and IIB)
Lymph nodes located around the upper third of the internal jugular vein and adjacent spinal accessory nerve, extending from the level of the skull base (above) to the level of the inferior border of the hyoid bone (below). The anterior (medial) boundary is stylohyoid muscle (the radiologic correlate is the vertical plane defined by the posterior surface of the submandibular gland) and the posterior (lateral) boundary is the posterior border of the stemocleidomastoid muscle. Sublevel IlA nodes are located anterior (medial) to the vertical plane defined by the spinal accessory nerve. Sublevel IlB nodes are located posterior lateral to the vertical plane defined by the spinal accessory nerve. (The radiologic correlate is the lateral border of the internal jugular on a contrast-enhanced CT scan.) The upper jugular nodes are at greatest risk for harboring metastases from cancers arising from the oral cavity, nasal cavity, nasopharynx, oropharynx, hypopharynx, larynx, and parotid gland.
Middle jugular lymph nodes (level III)
Lymph nodes located around the middle third of the internal jugular vein, extending from the inferior border of the hyoid bone (above) to the inferior border of the cricoid cartilage (below). The anterior (medial) boundary is the lateral border of the sternohyoid muscle, and the posterior (lateral) boundary is the posterior border of the sternocleidomastoid muscle. These nodes are at greatest risk for harboring metastases from cancers arising from the oral cavity, nasopharynx, oropharynx, hypopharynx, and larynx.
Lower jugular lymph nodes (level IV)
Lymph nodes located around the lower third of the internal jugular vein, extending from the inferior border of the cricoid cartilage (above) to the clavicle below. The anterior (medial) boundary is the lateral border of the sternohyoid muscle and the posterior (lateral) boundary is the posterior border of the stemocleidomastoid muscle. These nodes are at greatest risk for harboring metastases from cancers arising from the hypopharynx, thyroid, cervical esophagus, and larynx.
Posterior triangle lymph nodes (sublevels VA and VB)
This group is composed predominantly of the lymph nodes located along the lower half of the spinal accessory nerve and the transverse cervical artery. The supraclavicular nodes also are included in the posterior triangle group. The superior boundary is the apex formed by the convergence of the stemocleidomastoid and trapezius muscles; the inferior boundary is the clavicle; the anterior (medial) boundary is the posterior border of the stemocleidomastoid muscle; and the posterior (lateral) boundary is the anterior border of the trapezius muscle. Thus, sublevel VA includes the spinal accessory nodes, whereas sublevel VB includes the nodes following the transverse cervical vessels and the supraclavicular nodes, with the exception of the Virchow node, which is located in level N . The posterior triangle nodes are at greatest risk for harboring metastases from cancers arising from the nasopharynx, oropharynx, and cutaneous structures of the posterior scalp and neck.
Anterior compartment lymph nodes (level VI)
Lymph nodes in this compartment include the pretracheal and paratracheal nodes, precrjcoid (Delphian) node, and the perithyroidal nodes, including the lymph nodes along the recurrent laryngeal nerves. The superior boundary is the hyoid bone; the inferior boundary is the suprasternal notch; and the lateral boundaries are the common carotid arteries. These nodes are at greatest risk for harboring metastases from cancers arising from the thyroid gland, glottic and subglottic larynx, apex of the piriforrn sinus, and cervical esophagus.
Superior mediastinal lymph nodes (level VII)
Lymph nodes in this group include pretracheal, paratracheal, and esophageal groove lymph nodes, extending from the level of the suprastemal notch cephalad and up to the innominate artery caudad. These nodes are at greatest risk of involvement by thyroid cancer and cancer of the esophagus.
