Malignant Melanoma

TNM 7 classification

TNM 6 classification

1. Rules for Classification

There should be histological confirmation of the disease.

The following are the procedures for assessing N and M categories:

N categories. Physical examination and imaging
M categories. Physical examination and imaging

2. Regional Lymph Nodes

The regional lymph nodes are those appropriate to the site of the primary tumour. See .

3. TNM Clinical Classification

3.1. T - Primary Tumour
The extent of the tumour is classified after excision, see pT, pT - Primary Tumour.


3.2. N - Regional Lymph Nodes

NX. Regional lymph nodes cannot be assessed
N0. No regional lymph node metastasis
N1. Metastasis in one regional lymph node

N1a. only microscopic metastasis (clinically occult)
N1b. macroscopic metastasis (clinically apparent)

N2. Metastasis in two or three regional lymph nodes or intralymphatic regional metastasis

N2a. only microscopic nodal metastasis
N2b. macroscopic nodal metastasis
N2c. satellite or in-transit metastasis without regional nodal metastasis

N3. Metastasis in four or more regional lymph nodes, or matted metastatic regional lymph nodes, or satellite or in-transit metastasis with metastasis in regional lymph node(s)


Note: Satellites are tumour nests or nodules (macro- or microscopic) within 2 cm of the primary tumour. In-transit metastasis involves skin or subcutaneous tissue more than 2 cm from the primary tumour but not beyond the regional lymph nodes.


3.3. M - Distant Metastasis

MX. Distant metastasis cannot be assessed
M0. No distant metastasis
M1. Distant metastasis

M1a. Skin, subcutaneous tissue or lymph node(s) beyond the regional lymph nodes
M1b. Lung
M1c. Other sites, or any site with elevated serum lactic dehydrogenase (LDH)

4. pTNM Pathological Classification

See also: Additional site-specific recommendations for pT and pN


4.1. pT - Primary Tumour

pTX. Primary tumour cannot be assessed*
pT0. No evidence of primary tumour
pTis. Melanoma in situ (Clark level I) (atypical melanocytic hyperplasia, severe melanocytic dysplasia, not an invasive malignant lesion)

pT1. Tumour 1 mm or less in thickness

pT1a. Clark level II or III, without ulceration
pT1b. Clark level IV or V, or with ulceration

pT2. Tumour more than 1 mm but not more than 2 mm in thickness

pT2a. without ulceration
pT2b. with ulceration

pT3. Tumour more than 2 mm but not more than 4 mm in thickness

pT3a. without ulceration
pT3b. with ulceration

pT4. Tumour more than 4 mm in thickness

pT4a. without ulceration
pT4b. with ulceration

4.2. pN - Regional Lymph Nodes
The pN categories correspond to the N categories.

pN0. Histological examination of a regional lymphadenectomy specimen will ordinarily include 6 or more lymph nodes. If the lymph nodes are negative, but the number ordinarily examined is not met, classify as pN0. Classification based solely on sentinel node biopsy without subsequent axillary lymph node dissection is designated (sn) for sentinel node, e.g., pN1(sn). (See in the Introduction.)

4.3. pM - Distant Metastasis
The pM categories correspond to the M categories.

5. Stage Grouping

Stage 0 pTis N0 M0 Stage I pT1 N0 M0 Stage IA pT1a N0 M0 Stage IB pT1b N0 M0 pT2a N0 M0 Stage IIA pT2b N0 M0 pT3a N0 M0 Stage IIB pT3b N0 M0 pT4a N0 M0 Stage IIC pT4b N0 M0 Stage III Any pT N1. N2. N3 M0 Stage IIIA pT1a-4a N1a. 2a M0 Stage IIIB pT1a-4a N1b. 2b, 2c M0 pT1b-4b N1a. 2a, 2c M0 Stage IIIC pT1b-4b N1b. 2b M0 Any pT N3 M0 Stage IV Any pT Any N M1

6. Summary

Skin Malignant Melanoma pT1a ≤1 mm, Level II or III, no ulceration pT1b ≤1 mm, Level IV or V, or ulceration pT2a >1-2 mm, no ulceration pT2b >1-2 mm, ulceration pT3a >2-4 mm, no ulceration pT3b >2-4 mm, ulceration pT4a >4 mm, no ulceration pT4b >4 mm, ulceration N1 1 node N1a microscopic N1b macroscopic N2 2-3 nodes or satellites/in-transit without nodes N2a 2-3 nodes microscopic N2b 2-3 nodes macroscopic N2c satellites or in-transit without nodes N3 ≥4 nodes; matted; satellites/in-transit with nodes