Irinotecan- vs oxaliplatin-based regimens for neoadjuvant chemotherapy in colorectal liver metastasis patients: A retrospective study

Table 1 Demographic and clinical characteristics of patients before propensity score matching

Patient demographic	All patients (n = 554)	Irinotecan group (n = 201)	Oxaliplatin group (n = 353)	P value
Age (yr)	57.1 ± 9.5	56.1 ± 9.6	57.7 ± 9.4	0.056
Sex ration (male:female)	193:361	62:139	131:222	0.137
Primary T stage				0.736
T1-2	64	22	42
T3-4	490	179	311
Primary N stage				0.036
N0	191	58	133
N1-2	363	143	220
Primary tumor location				0.613
Colon	322	114	208
Rectum	232	87	145
Primary tumor side				0.839
Right	75	28	47
Left	479	173	306
Timing of liver metastasis				< 0.001
Synchronous	482	157	325
Metachronous	72	44	28
Tumor number (median)	3 (1-10)	3 (1-9)	3 (1-10)	0.706
Tumor size (mm, mean ± SD)	27.6 ± 18.2	26.78 ± 17.2	29.0 ± 17.8	0.160
Localization of liver metastases				0.250
Unilobar	226	90	176
Bilobar	288	111	177
CEA level (ng/mL)	31.44 ± 85.3	24.93 ± 54.1	35.17 ± 98.65	0.175
CA 19-9 level (IU/mL)	215.4 ± 877.9	194.8 ± 232.8	227.4 ± 185.4	0.847
Extrahepatic metastasis				0.572
No	462	170	292
Yes	92	31	61
RAS mutation				0.174
Wildtype	332	128	204
Mutation	222	73	149
Biological agent				< 0.001
Cetuximab	118	57	61
Bevacizumab	187	97	90
No	249	47	202
Response				0.209
Complete response	5	0	5
Partial response	217	81	136
Stable disease	301	112	189
Progressive disease	31	8	23
Cycles	4 (1-16)	4 (1-12)	4 (1-16)	0.430
Concomitant ablation therapy	91	39	52	0.154
CRS
0-2	274	95	179
3-5	280	106	174
Resection				0.002
Simultaneous resection	145	41	104
Staged resection	409	160	249
Intraoperative blood loss (mL)	213 ± 198	204 ± 172	218 ± 212	0.437
Intraoperative RBC transfusion	24	10	14	0.289
Intraoperative RBC transfusion (U)	2 (1-12)	2 (1-6)	4 (2-12)	0.026
Operating time (min)	199 ± 74	190 ± 72	204 ± 76	0.039
Hepatic resection				0.357
Major resection	123	49	74
Minor resection	431	152	279
Margin status				0.308
Positive	72	30	42
Negative	482	171	311
Clavien-Dindo classification				0.057
I-II	164	53	111
II-V	32	7	25
Adjuvant chemotherapy				0.153
No	132	41	91
Yes	422	160	262

PSM: Propensity score matching; CEA: Carcinoembryonic antigen; CA 19-9: Carbohydrate antigen 19-9; RBC: Red blood cell; CRS: Clinical risk score.

Table 2 Demographic and clinical characteristics of patients after propensity score matching

Patient demographic	All patients (n = 350)	Irinotecan group (n = 175)	Oxaliplatin group (n = 175)	P value
Age (yr)	56.0 ± 4.2	56.2 ± 9.6	55.7 ± 10.1	0.632
Sex ration (male:female)	230:120	121:54	109:66	0.177
Primary T stage				0.433
T1-2	47	21	26
T3-4	303	154	149
Primary N stage				0.526
N0	104	51	53
N1-2	246	125	121
Primary tumor location				0.756
Colon	205	101	104
Rectum	145	74	71
Primary tumor side				0.745
Right	48	25	23
Left	302	150	152
Timing of liver metastasis				0.077
Synchronous	283	135	148
Metachronous	67	40	27
Tumor number (median)	2 (1-25)	2 (1-25)	2 (1-22)	0.422
Tumor size (mm, mean ± SD)	28.8 ± 18.9	29.2 ± 20.3	28.4 ± 17.5	0.681
Localization of liver metastases				0.493
Unilobar	190	98	92
Bilobar	160	77	83
CEA level (ng/mL)	27.81 ± 64.87	24.26 ± 55.81	31.36 ± 72.81	0.307
CA 19-9 level (IU/mL)	228.71 ± 203.76	212.92 ± 145.70	244.51 ± 266.39	0.894
Extrahepatic metastasis				0.311
No	293	150	143
Yes	57	25	32
RAS mutation				0.912
Wild type	221	111	110
Mutation	129	64	65
Biological agent				0.169
Cetuximab	100	53	47
Bevacizumab	167	88	79
No	83	34	49
Response				0.176
Complete response	1	0	1
Partial response	144	70	74
Stable disease	183	98	85
Progressive disease	22	7	15
Cycles	4 (0-10)	4 (0-10)	4 (0-10)	0.948
Concomitant ablation therapy	66	36	30	0.464
CRS				0.669
0-2	166	81	85
3-5	184	94	90
Simultaneous resection	88	39	49	0.443
Staged resection	262	136	126
Intraoperative blood loss (mL)	222 ± 211	201 ± 181	264 ± 235	0.024
Intraoperative RBC transfusion	15	8	7	0.117
Intraoperative RBC transfusion (U)	2 (1-12)	2 (1-6)	2 (2-6)	0.281
Operation time (min)	198 ± 73	188 ± 73	208 ± 72	0.012
Hepatic resection				0.886
Major resection	90	42	45
Minor resection	260	133	130
Margin status				0.367
Positive	32	17	15
Negative	318	158	160
Clavien-Dindo classification				0.019
I-II	102	43	59
III-V	22	7	15
Adjuvant chemotherapy				0.352
No	132	41	91
Yes	422	160	262

PSM: Propensity score matching; CEA: Carcinoembryonic antigen; CA 19-9: Carbohydrate antigen 19-9; RBC: Red blood cell; CRS: Clinical risk score.

Table 3 Univariable and multivariable analyses of factors associated with progression-free survival

Variable	Univariable analysis			Multivariable analysis
	HR	95%CI	P value	HR	95%CI	P value
Age, yr
> 60	Ref
≤ 60	0.878	0.682-1.131	0.314
Gender
Male	Ref
Female	0.949	0.733-1.230	0.694
Primary T stage
1-2	Ref
3-4	1.183	0.820-1.706	0.369
Primary N stage
N0	Ref
N1-2	1.090	0.952-1.248	0.212
Location tumor
Colon	Ref
Rectum	0.869	0.676-1.116	0.270
Primary tumor location
Left	Ref			Ref
Right	1.508	1.072-2.121	0.018	1.413	0.991-2.015	0.056
Disease-free interval
> 12 mo	Ref			Ref
≤ 12 mo	1.487	1.068-2.071	0.019	1.156	0.788-1.696	0.459
CEA
≤ 200	Ref
> 200	1.340	0.689-2.607	0.388
CA 19-9
≤ 100	Ref			Ref
> 100	1.528	1.077-2.167	0.017	1.521	1.032-2.241	0.034
Tumor size
≤ 5 cm	Ref			Ref
> 5 cm	1.149	1.019-1.554	0.028	1.479	1.062-2.060	0.021
Tumor no.
≤ 1	Ref			Ref
> 1	1.702	1.284-2.255	0.000	1.446	1.077-2.146	0.014
CRS
0-2	Ref			Ref
3-5	1.665	1.298-2.135	0.000	1.256	0.894-1.765	0.189
RAS status
Wild	Ref			Ref
Mutation	1.641	1.276-2.110	0.000	1.468	1.127-1.913	0.004
Extrahepatic metastases
No	Ref
Yes	1.081	0.781-1.496	0.638
Biological agent
Cetuximab
Bevacizumab	Ref
No	1.057	0.910-1.228	0.469
Response
Complete response
Partial response
Stable disease	Ref			Ref
Progressive disease	1.564	1.067-2.292	0.022	1.830	1.211-2.764	0.004
Hepatic resection
Minor	Ref
Major	0.997	0.753-1.320	0.984
Concomitant ablation
No	Ref			Ref
Yes	1.634	1.195-2.236	0.002	1.002	0.641-1.568	0.992
Stage resection
No	Ref
Yes	0.839	0.682-1.033	0.098
Margin status
R0	Ref
R1	0.878	0.581-1.327	0.537
Distribution
Unilobar	Ref			Ref
Bilobar	1.277	1.067-1.528	0.008	1.112	0.875-1.413	0.385
Extrahepatic metastases
Yes	Ref
No	1.081	0.781-1.496	0.638
Adjuvant chemotherapy
No	Ref
Yes	0.885	0.654-1.198	0.430
Clavien-Dino classification
I-II	Ref
III-V	1.018	0.833-1.244	0.859
RBC transfusion
Yes	Ref
No	0.857	0.456-1.614	0.634

PFS: Progression-free survival; HR: Hazard ratio; CEA: Carcinoembryonic antigen; CA 19-9: Carbohydrate antigen 19-9; RBC: Red blood cell; CI: Confidence interval; CRS: Clinical risk score.