Table 3.

Results of the multivariate regression model analysis

Factor	Hazard ratio	95% confidence interval		p
		Lower	Upper
Perineural invasion	1.337	0.612	2.921	NS
Tumour site	1.151	0.881	1.502	NS
T stage	1.755	1.321	2.330	< 0.0001
Extracted lymph nodes	0.972	0.948	0.997	0.026
Preoperative Ca19-9 serum level	1	1.000	1.001	NS
Ca19-9 cut-off (3.5 IU/ml)	1.045	0.528	2.068	NS

NS = not significant