Table 5.

Multivariate survival results according to the presence or absence of bone metastases

	PFS		OS
Without bone metastasis	HR (95 CI)	p-value	HR (95 CI)	p-value
Opioid Using
Yes	NR		NR
No	NR		NR
Tramadol
No	Ref	0.027	Ref	0.231
Yes	2.260 (1.097-4.655)		2.577 (0.547-12.134)
Morphine
Yes	Ref	0.742	3.009 (0.756-11.98)	0.118
No	0.836 (0.288-2.427)		Ref
Fentanyl
Yes	1.725 (0.318-9.361)	0.527	1.53 (0.144-16.208)	0.724
No	Ref		Ref
Codein
No	Ref	0.572	Ref	0.39
Yes	1.963 (0.19-20.315)		3.865 (0.177-84.385)
With bone metastasis
Opioid Using
Yes	1.018 (0.045-23.128)	0.991	Ref	0.62
No	Ref		0.551 (0.052-5.823)
Tramadol
No	Ref	0.621	Ref	0.275
Yes	1.268 (0.495-3.251)		1.622 (0.68-3.86)
Morphine
Yes	Ref	0.719	Ref	0.844
No	0.739 (0.143-3.834)		0.86 (0.191-3.869)
Fentanyl
Yes	Ref	0.147	Ref	0.019
No	0.524 (0.219-1.256)		0.38 (0.169-1.854)
Codein
No	Ref	0.744	Ref	0.985
Yes	0.88 (0.408-1.896)		1.007 (0.456-2.224)

HR, hazard ratio; NR, not reached; OS, Overall survival; PFS, progression-free survival; Ref, reference; SCC, squamous cell carcinoma.