Table I.
The 8th Edition of the American Joint Committee of Cancer (AJCC) Melanoma Staging System.
| T category | Tumor thickness | Ulceration |
|---|---|---|
|
| ||
| Tx -The thickness of the primary tumor cannot be assessed | Not applicable | Not applicable |
|
| ||
| T0 - No evidence of primary tumor | Not applicable | Not applicable |
|
| ||
| Tis - Melanoma in situ | Not applicable | Not applicable |
|
| ||
| T1 | ≤ 1.0 mm | Unknown/unspecified |
|
| ||
| T1a | < 0.8 mm | No ulceration |
| T1b | < 0.8 mm | With ulceration |
| 0.8–1 mm | With/without ulceration | |
|
| ||
| T2 | 1–2 mm | Unknown/unspecified |
|
| ||
| T2a | 1–2 mm | Without ulceration |
| T2b | With ulceration | |
|
| ||
| T3 | 2–4 mm | Unknown/unspecified |
|
| ||
| T3a | 2–4 mm | Without ulceration |
| T3b | With ulceration | |
|
| ||
| T4 | > 4 mm | Unknown/unspecified |
|
| ||
| T4a | > 4 mm | Without ulceration |
| T4b | With ulceration | |
|
| ||
| N category | The number of affected regional lymph nodes | |
|
| ||
| Nx | Lymph nodes cannot be evaluated | |
|
| ||
| N0 | No regional metastases detected | |
|
| ||
| N1 | Single lymph node metastases or transit/satellite metastases without lymph node metastasis | |
|
| ||
| N2 | Metastases in two or three nodes or metastases in transit/satellites with metastasis in one node | |
|
| ||
| N3 | Metastases in four or more lymph nodes or transit metastases/satellites with metastasis in two or more nodes or any number of lymph node metastases with/without transit/satellite metastases | |
|
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| M category | Anatomical location | |
|
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| M0 | No distant metastases detected | |
|
| ||
| M1 | Distant metastasis detected | |