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 |
|
| N2a |
|
| 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 |
|
| N3a | Metastasis in a lymph node, tumor size > 6 cm, and absence of extranodal extension |
| N3b |
|
| M – Distant metastasis | |
| M0 | No distant metastasis |
| M1 | Distant metastasis |
References
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