A Review of the Aetiopathogenesis and Clinical and Histopathological Features of Oral Mucosal Melanoma

Table 2

American Joint Committee on Cancer (AJCC) TNM staging of mucosal melanoma [1–3, 35].

T: primary tumour		N: regional lymph node	M: distant metastasis
T3: mucosal disease		NX: regional lymph nodes that cannot be assessed	MO: no distant metastasis
T4a: moderately advanced disease involving deep soft tissues, bone, and overlying skin		NO: no regional lymph node metastasis	M1: distant metastasis present
T4b: very advanced disease involving brain, dura, skull base, lower cranial nerves (IX, X, XI, and XII), masticator space, paravertebral space, or mediastinal structures		N1: regional lymph node metastasis present
Different clinical stages of oral mucosal melanoma
Stage	T	N	M
Stage III	T3	NO	MO
Stage IVa	T4a	NO	MO
	or T3-T4a	N1	MO
Stage IVb	T4	Any N	MO
Stage IVc	Any T	Any N	M1