Table 3 TNM classifications of OSCC in the 7 ^th and 8 ^th edition.

TNM, 7 th edition		TNM, 8 th edition
		p16-negative		p16-positive
T		T		T
c/p T1	≤2 cm	c/p T1	≤2 cm	c/p T1	≤2 cm
c/p T2	>2 cm, ≤4 cm	c/p T2	>2 cm, ≤4 cm	c/p T2	>2 cm, ≤4 cm
c/p T3	>4 cm without extension to the lingual epiglottis	c/p T3	>4 cm without extension to the lingual epiglottis	c/p T3	>4cm without extension to the lingual epiglottis
c/p T4a	Infiltration of the larynx, outer tongue muscles, hard palate, mandible	c/p T4a	Infiltration of the larynx, outer tongue muscles, hard palate, mandible, lamina med. pterygoid process	c/p T4	Infiltration of the larynx, outer tongue muscles, lamina med./lat. pterygoid process, hard palate, mandible, lateral pterygoid muscle, skull base, ACI, lateral nasopharynx
c/p T4b	Infiltration of the lateral pterygoid muscle, skull base, ACI	c/p T4b	Infiltration of the lateral pterygoid muscle, skull base, ACI
N		cN		cN
c/p N0	No regional lymph node metastases	cN0	No regional lymph node metastases	cN0	No regional lymph node metastases
c/p N1	Ipsilateral, solitary ≤3 cm	cN1	Ipsilateral, solitary ≤3 cm	cN1	Ipsilateral, solitary or multiple, ≤6 cm
c/p N2a	Ipsilateral, solitary, >3-6 cm	cN2a	Ipsilateral, multiple, >3-6 cm	cN2	Contralateral or bilateral, ≤6 cm
c/p N2b	Ipsilateral, multiple, ≤6 cm	cN2b	Ipsilateral, multiple, ≤6 cm
c/p N2c	Bilateral, contralateral ≤6 cm	cN2c	Bilateral, contralateral ≤6 cm
c/p N3	Metastases >6 cm	cN3a	Metastases >6 cm	cN3	Metastases >6 cm
		cN3b	ECS
		pN		pN
		pN0	No regional lymph node metastases	pN0	No regional lymph node metastases
		pN1	Ipsilateral solitary ≤3 cm	pN1	≤4 affected lymph nodes
		pN2a	Ipsilateral solitary, ≤3 with ECS or ≤6 cm without ECS	pN2	≥5 affected lymph nodes
		pN2b	Ipsilateral multiple ≤6 cm, without ECS
		pN2c	Bilateral, contralateral ≤6 cm without ECS
		pN3a	Metastases >6 cm, no ECS
		pN3b	Metastases >3 cm with ECS or contra-/bilateral with ECS