. Author manuscript; available in PMC: 2023 Oct 26.

Published in final edited form as: Otolaryngol Head Neck Surg. 2023 Jan 28;169(1):69–75. doi: 10.1177/01945998221116746

Table 3.

Post Hoc Cox Regression Analysis.^a

	Skin invasion		Bone invasion		PNI
	P value	HR (95% CI)	P value	HR (95% CI)	P value	HR (95% CI)
OS
2 y	.037^b	2.113 (1.046-4.270)	.064	2.792 (0.944-8.263)	.0001^b	6.049 (2.791-13.106
5 y	.018^b	2.224 (1.145-4.321)	.067	2.474 (0.938-6.523)	.0001^b	5.049 (2.529-10.082)
DFS
2 y	.142	1.664 (0.843-3.283)	.110	2.107 (0.845-5.255)	.0001^b	5.264 (2.562-10.812)
5 y	.069	1.838 (0.954-3.541)	.086	2.192 (0.894-5.371)	.0001^b	4.397 (2.251-8.588)

Abbreviations: DFS, disease-free survival; OS, overall survival; PNI, perineural invasion.

Post hoc Cox regression analysis to evaluate effect of skin invasion on survival while controlling for bone invasion and PNI. Lip cases were excluded (n = 58). When bone invasion and PNI are controlled for, skin invasion remained statistically significant with 2- and 5-year OS. When skin invasion and bone invasion are controlled for, PNI remains statistically significant for 2- and 5-year OS and 2- and 5-year DFS.

P < .05.