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Squamous cell carcinoma of the skin classification

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Roukoz A. Karam, M.D.[2]

Overview

Classification

Category Criteria
T – Primary tumor
TX Primary tumor cannot be assessed
Tis Carcinoma in situ
T1 Tumor ≤ to 2 cm
T2 Tumor > 2 cm, and ≤ to 4 cm
T3 Tumor > 4 cm or minor bone erosion or perineural invasion or deep invasion
T4 Tumor with gross cortical bone/marrow, skull base invasion and/or skull base foramen invasion
T4a Tumor with gross cortical bone/marrow invasion
T4b Tumor with skull base invasion and/or skull base foramen involvement
N – Regional lymph nodes
NX Regional lymph nodes cannot be assessed
N0 No regional lymph node metastasis
N1 Metastasis in a single ipsilateral lymph node, tumor size ≤ 3 cm, and no extranodal extension
N2
  • Metastasis in a single ipsilateral lymph node, tumor size ≤ 3 cm, and presence of extranodal extension; or
  • Tumor size > 3 cm but ≤ 6 cm without extranodal extension; or
  • Metastasis in a single ipsilateral lymph node, tumor size ≤ 3 cm, and presence of extranodal extension; or
  • Metastases in multiple ipsilateral lymph nodes, tumor size ≤ 6 cm without extranodal extension; or
  • In bilateral or contralateral lymph node(s), tumor size ≤ 6 cm without extranodal extension
N2a
  • Metastasis in a single ipsilateral lymph node, tumor size ≤ 3 cm, and presence of extranodal involvement; or
  • Single ipsilateral node larger, tumor size > 3 cm and ≤ 6 cm, without extranodal extension
N2b Metastases in multiple ipsilateral nodes, tumor size ≤ 6 cm, and without extranodal extension
N2c Metastases in bilateral or contralateral lymph node(s), tumor size ≤ 6 cm, and without extranodal extension
N3
  • Metastasis in a lymph node, tumor size > 6 cm, and without extranodal extension; or
  • In a single ipsilateral node, tumor size > 3 cm, and presence of extranodal extension; or
  • Multiple ipsilateral, contralateral, or bilateral nodes with any extranodal exension; or
  • Single contralateral node of any size with any extranodal extension
N3a Metastasis in a lymph node, tumor size > 6 cm, and absence of extranodal extension
N3b
  • Metastasis in a single ipsilateral node, tumor size > 3 cm, and in presence of extranodal extension; or
  • Multiple ipsilateral, contralateral, or bilateral nodes, with any extranodal extension; or
  • Single contralateral node of any size and with any extranodal extension
M – Distant metastasis
M0 No distant metastasis
M1 Distant metastasis

References


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