Table 3. Overall survival (OS) in subgroups.

Subgroup	PBT	OS (95% CI) [years]	p (log rank test)
Age < 60	no	7.03 (6.25–7.81)	<0.001
	yes	2.98 (1.71–4.24)
ASA1 & 2	no	6.93 (6.22–7.64)	0.365
	yes	5.01 (2.55–7.48)
Normemic patients	no	7.35)6.64–8.07)	0.017
	yes	4.16 (2.95–5.38)
p16-positive HNSCC	no	6.04 (5.47–6.62)	0.042
	yes	3.80 (2.71–4.89)
pT1 & 2	no	6.93 (6.27–7.59)	<0.001
	yes	3.31 (2.36–4.26)
pN0-2a	no	6.97 (6.36–7.59)	0.029
	yes	4.23 (3.29–5.17)