Table 1.
TNM Staging Categories for Cutaneous Melanoma
| Classification | Thickness (mm) | Ulceration Status/Mitoses |
|---|---|---|
| T | ||
| Tis | NA | NA |
| T1 | ≤ 1.00 | a: Without ulceration and mitosis < 1/mm2 b: With ulceration or mitoses ≥ 1/mm2 |
| T2 | 1.01-2.00 | a: Without ulceration |
| b: With ulceration | ||
| T3 | 2.01-4.00 | a: Without ulceration |
| b: With ulceration | ||
| T4 | > 4.00 | a: Without ulceration |
| b: With ulceration |
| N | No. of Metastatic Nodes | Nodal Metastatic Burden |
|---|---|---|
| N0 | 0 | NA |
| N1 | 1 | a: Micrometastasis* |
| b: Macrometastasis† | ||
| N2 | 2-3 | a: Micrometastasis* |
| b: Macrometastasis† | ||
| c: In transit metastases/satellites without metastatic nodes | ||
| N3 | 4+ metastatic nodes, or matted nodes, or in transit metastases/satellites with metastatic nodes |
| M | Site | Serum LDH |
|---|---|---|
| M0 | No distant metastases | NA |
| M1a | Distant skin, subcutaneous, or nodal metastases | Normal |
| M1b | Lung metastases | Normal |
| M1c | All other visceral metastases | Normal |
| Any distant metastasis | Elevated |
Abbreviations: NA, not applicable; LDH, lactate dehydrogenase.
*
Micrometastases are diagnosed after sentinel lymph node biopsy.
†
Macrometastases are defined as clinically detectable nodal metastases confirmed pathologically.