Outcomes of microwave versus radiofrequency ablation for hepatocellular carcinoma: A systematic review and meta-analysis

Table 2 Summary of the comparison of OS and local recurrence rates between microwave ablation versus radiofrequency ablation for intrahepatic hepatocellular lesions in both cohort studies and RCTs according to year of follow-up

Endpoint	Study design	No. of studies	OR	95%CI	P for significance	I2	P for heterogeneity
Overall survival – OR
1Y	Prospective	1	3.00	0.33-27.48	0.331	-	-
	Retrospective	11	1.19	0.71-1.99	0.513	0	0.72
	RCT	4	1.95	0.71-5.34	0.194	35.5	0.20
2Y	Retrospective	7	1.27	0.75-2.18	0.377	36.6	0.15
	RCT	1	1.84	0.54-6.28	0.333	-	-
3Y	Prospective	1	1.69	0.59-4.81	0.328	-	-
	Retrospective	9	1.14	0.75-1.73	0.554	58.1	0.01
	RCT	2	0.98	0.62-1.54	0.929	0	0.62
4Y	Retrospective	5	0.77	0.46-1.29	0.323	60.8	0.04
5Y	Prospective	2	1.49	0.31-7.22	0.620	71.2	0.06
	Retrospective	5	0.86	0.62-1.19	0.357	34.8	0.19
	RCT	2	0.79	0.50-1.15	0.197	0	0.76
Unspecified	Retrospective	4	1.54	1.15-2.05	0.004	0	0.50
	RCT	2	1.47	0.73-2.96	0.282	0	0.50
Local recurrence rate – OR
1Y	Retrospective	4	0.78	0.29-2.11	0.619	62.8	0.04
	RCT	3	1.09	0.39-3.05	0.872	0	0.40
2Y	Retrospective	4	1.00	0.40-2.45	0.992	76.2	0.06
	RCT	2	1.02	0.23-4.58	0.975	70.4	0.07
3Y	Retrospective	2	0.80	0.11-5.97	0.826	84.8	0.01
	RCT	1	0.73	0.30-1.8	0.493	-	-
4Y	Retrospective	2	2.14	1.12-4.07	0.021	0	0.86
5Y	Prospective	1	2.22	0.49-10.02	0.301	-	-
	RCT	1	0.52	0.30-0.91	0.023	-	-
Unspecified	Prospective	3	0.60	0.25-1.39	0.233	0	0.44
	Retrospective	20	0.67	0.51-0.87	0.002	37.2	0.05
		1	0.26	0.06-1.07	0.063	-	-

OS: Overall survival; OR: Odds ratio; CI: Confidence interval; RCT: Randomised controlled trial.