Table 2.

Univariate and multivariate analysis of factors associated with overall survival and recurrence-free survival after systemic therapy plus radiofrequency ablation of colorectal liver metastases.

Variables		No. of patients	Overall survival					Recurrence-free survival
			Univariate analysis			Multivariate analysis		Univariate analysis			Multivariate analysis
			Median months (95% CI)	5-years, % (95% CI)	p-value	HR (95% CI)	p-value	Median months (95% CI)	5-years, % (95% CI)	p-value	HR (95% CI)	p-value
Patient and tumor characteristics
Age					0.690					0.254
	≤ 60 years	21	21.9 (15.9-38.0)	15.7 (3.4-34.7)				7.0 (4.9-10.9)	14.3 (3.0-32.0)
	> 60 years	92	25.0 (20.9-31.0)	16.5 (9.5-25.0)				6.9 (5.0-9.0)	5.4 (2.7-10.9)
Gender					0.643					0.730
	Male	69	25.0 (18.0-31.1)	15.2 (7.4-25.1)				6.97 (5.0-9.9)	7.3 (2.4-14.5)
	Female	44	25.0 (18.1-36.0)	18.2 (8.3-30.8)				6.97 (4.9-9.0)	6.8 (1.6-16.0)
Primary tumor					0.527					0.505
	Colon	89	24.0 (18.0-31.1)	15.1 (8.2-23.6)				6.9 (5.0-8.9)	6.7 (2.5-12.8)
	Rectum	24	30.0 (22.0-36.9)	20.8 (7.3-38.9)				7.0 (5.9-10.9)	8.3 (0.8-22.3)
Node status					0.924					0.967
	Positive	79	28.0 (21.9-33.9)	14.4 (7.4-23.1)				6.9 (5.0-9.1)	7.6 (2.8-14.4)
	Negative	34	20.0 (16.0-31.9)	21.5 (9.1-37.4)				6.4 (4.9-10.0)	5.8 (0.6-16.1)
CLM					0.967					0.056
	Synchronous	24	25.5 (22.0-36.0)	13.9 (3.0-31.0)				9.5 (6.0-11.9)	4.2 (0.7-15.6)
	Metachronous	89	25.0 (18.0-33.0)	17.0 (9.7-25.7)				6.0 (4.9-7.1)	7.8 (3.2-14.3)
CEA level before RFA					<0.001	1.68 (1.10-2.57)	0.012			0.004
	≤ 100 ng/ml	71	31.1 (25.0-36.0)	21.5 (12.6-32.2)				8.9 (6.9-10.0)	9.8 (4.1-17.8)
	> 100 ng/ml	42	15.5 (11.1-25.0)	7.5 (1.5-17.6)				5.0 (4.0-6.0)	2.4 (0.6-9.1)
Maximum size of CLM					<0.001	1.78 (1.09-2.90)	0.022			<0.001	2.18 (1.36-3.48)	0.001
	≤ 3 cm	79	31.9 (24.0-36.0)	22.3 (13.6-32.5)				9.0 (6.9-10.0)	10.1 (4.5-17.7)
	3-5 cm	34	14.5 (10.0-22.0)	2.94 (2.0-11.1)				4.0 (3.0-5.0)	0 (.-.)
Number of CLM					<0.001	2.68 (1.62-4.46)	<0.001			0.012	1.99 (1.25-3.17)	0.004
	1-3	87	29.0 (23.0-35.0)	20.17 (12.3-29.3)				7.0 (6.0-9.0)	9.2 (4.1-16.1)
	4-5	26	13.5 (10.0-26.9)	0.00 (-)				4.5 (3.0-9.0)	0 (.-.)
Systemic therapy before RFA
Lines of therapy received					0.002	1.88 (1.21-2.92)	0.001			0.012	1.67 (1.10-2.55)	0.017
	1	66	31.9 (26.9-36.0)	18.2 (9.7-28.7)				9.0 (7.03-10.02)	6.1 (1.6-13.0)
	≥2	47	13.0 (10.0-17.9)	13.7 (5.3-25.2)				4.0 (3.02-5.03)	8.5 (2.3-18.1)
Oxaliplatin used in last line					0.482					0.160
	Yes	53	24.0 (18.0-35.0)	20.1 (10.4-31.9)				7.9 (5.0-10.1)	9.4 (3.2-18.6)
	No	60	26.0 (18.0-31.9)	12.6 (5.2-22.7)				6.0 (5.0-8.0)	5.0 (1.0-11.9)
Irinotecan used in last line					0.673					0.140
	Yes	42	25.0 (15.9-33.0)	13.2 (4.2-26.1)				5.5 (4.9-7.0)	7.1 (1.4-16.7)
	No	71	25.0 (18.0-34.0)	17.7 (9.7-27.5)				7.9 (5.9-9.9)	7.0 (2.3-14.1)
Bevacizumab used in last line					0.425					0.920
	Yes	24	23.0 (18.0-33.0)	24.1 (8.7-43.9)				6.0 (4.9-7.0)	12.5 (2.6-28.3)
	No	89	26.0 (18.0-33.0)	14.4 (7.8-22.6)				6.9 (5.0-9.9)	5.6 (1.8-11.3)
Cetuximab used in last line					0.236					0.126
	Yes	8	34.5 (22.0-38.5)	25.0 (3.1-58.4)				11.0 (6.0-12.0)	12.5 (0.2-42.3)
	No	105	25.0 (18.0-29.9)	15.6 (9.2-23.4)				7.0 (5.0-8.0)	6.7 (2.7-12.2)
Response to last line regimen					<0.001	5.28 (3.18-8.77)	<0.001			<0.001	3.30 (2.09-5.20)	<0.001
	Partial remission	63	36.0 (32.9-46.9)	29.1 (18.3-41.2)				10.0 (9.0-12.0)	12.7 (5.7-22.0)
	Stable disease	21	21.9 (15.9-25.0)	0.00 (.-.)				5.9 (4.9-7.0)	0 (.-.)
	Progressive disease	29	9.03 (8.0-10.9)	0.00 (.-.)				3.0 (2.9-4.0)	0 (.-.)

95% CI, 95% confidence interval; CEA, carcinoembryonic antigen; CLM, colorectal liver metastases; HR, hazard ratio; RFA, radiofrequency ablation.