Neoadjuvant chemotherapy for patients with resectable colorectal cancer liver metastases: A systematic review and meta-analysis

Table 2 Meta-analysis results

Outcome indicators	No. of study	Patients (n)			HR/OR/SMD (95%CI)	P value	Heterogeneity
		NAC	non-NAC				χ2	I²	P value
5-year overall survival	22	2580		4218	0.49 (0.39-0.61)	P < 0.01	14.38	0.00%	P = 0.853
5-year disease free survival	13	1643		2864	0.48 (0.36-0.63)	P < 0.01	5.68	0.00%	P = 0.931
Duration of surgery	8	1980		2396	0.41 (0.01-0.82)	P < 0.05	172.79	95.90%	P = 0.000
Number of liver metastases	12	1017		1096	0.73 (0.02-1.43)	P < 0.05	549.46	98.00%	P = 0.000
Blood loss during surgery	6	474		646	0.53 (-0.05-1.10)	P = 0.072	90.12	94.50%	P = 0.000
Length of hospital stay (d)	6	605		565	0.01 (-0.61-1.02)	P = 0.624	184.79	97.30%	P = 0.000
Size of largest metastases (cm)	13	1226		1539	0.03 (-0.31-0.30)	P = 0.980	168.39	92.90%	P = 0.000
Synchronous metastases	19	2355		2553	1.17 (0.90-1.58)	P = 0.221	43.91	65.80%	P = 0.000
Major liver resection	14	2780		3133	1.06 (0.97-1.22)	P = 0.143	5.21	0.00%	P = 0.970
Lymph node metastasis	16	1523		2128	1.24 (1.07-1.43)	P < 0.05	29.26	49.50%	P = 0.013
R0 liver resection	7	723		976	0.85 (0.61-1.18)	P = 0.336	6.29	4.60%	P = 0.391
Perioperative complications	17	2886		3161	1.00 (0.76-1.31)	P = 0.980	51.82	69.10%	P = 0.000
Bile leakage	10	2244		2364	1.10 (0.84-1.43)	P = 0.481	4.77	0.00%	P = 0.782
Surgical site infection	8	2065		2056	0.94 (0.76-1.16)	P = 0.571	9.68	27.70%	P = 0.208
Liver failure	7	2025		1939	1.04 (0.76-1.42)	P = 0.813	5.77	13.40%	P = 0.329
Blood transfusion	5	1805		1710	1.07 (0.90-1.29)	P = 0.438	5.95	32.80%	P = 0.203

NAC: Neoadjuvant chemotherapy group; non-NAC: No neoadjuvant chemotherapy group; HR: Hazard ratio; OR: Odds ratio; SMD: Standard mean difference.