Impact of perioperative blood transfusion on oncological outcomes in ampullary carcinoma patients underwent pancreaticoduodenectomy

Table 4 Univariable and multivariable Cox regression analyses of recurrence-free survival in ampullary carcinoma patients

Characteristic	Univariable analysis		Multivariable analysis
	HR (95%CI)	P value	HR (95%CI)	P value
Perioperative Blood Transfusion
No	Reference		Reference
Yes	0.886 (0.607-1.293)	0.531	0.983 (0.667-1.447)	0.929
RBC units
0	Reference
1-4 units	0.854 (0.579-1.261)	0.428
≥ 5 units	1.282 (0.550-2.989)	0.565
Sex
Male	Reference
Female	0.976 (0.665-1.431)	0.9
Age (yr)
≤ 60	Reference		Reference
> 60	0.422 (0.282-0.631)	< 0.001	0.886 (0.407-1.928)	0.760
Operation time
≤ 6 h	Reference
> 6 h	1.194 (0.780-1.829)	0.414
Tumor size (cm)
≤ 2.0 cm	Reference		Reference
> 2.0 cm	1.458 (0.998-2.129)	0.051	1.121 (0.745-1.687)	0.583
Differentiation
Well	Reference		Reference
Moderate	0.892 (0.586-1.358)	0.594	1.100 (0.702-1.723)	0.679
Poor	0.511 (0.294-0.889)	0.018	0.970 (0.499-1.884)	0.928
T stage
T1	Reference		Reference
T2	1.451 (0.757-2.784)	0.262	1.239 (0.611-2.514)	0.553
T3	3.092 (1.656-5.773)	< 0.001	2.284 (0.874-4.968)	0.098
N stage
N0	Reference		Reference
N1	2.201 (1.449-3.343)	< 0.001	1.636 (0.932-2.873)	0.087
N2	3.248 (1.488-7.089)	0.003	2.441 (0.935-6.372)	0.068
Blood vessel invasion
No	Reference		Reference
Yes	2.351 (1.548-3.573)	< 0.001	1.744 (1.077-2.824)	0.024
Postoperative complications
No	Reference
Yes	0.959 (0.643-1.431)	0.839
Adjuvant treatment
No	Reference		Reference
Yes	1.501 (0.999-2.256)	0.051	0.711 (0.420-1.205)	0.205