Effect of primary tumor side on survival outcomes in metastatic colorectal cancer patients after hepatic arterial infusion chemotherapy

Table 1 Patient characteristics

Variable	Left side (n = 135)	Right side (n = 33)	P-value
Age, mean (range), years	60.5 (27-85)	63.8 (37-83)	0.392
Men, n (%)	95 (70.4)	20 (60.6)	0.279
Previous system treatment, n (%)			0.455
Only first line	89 (65.9)	24 (72.7)
Second line or more	46 (34.1)	9 (27.3)
Extrahepatic metastasis, n (%)	73 (54.1)	21 (63.6)	0.321
Primary tumor resected, n (%)			0.173
No surgery	22 (16.2)	10 (30.3)
Palliative surgery	49 (36.3)	11 (33.3)
Radical surgery	64 (47.4)	12 (36.4)
Synchronous metastases, n (%)	103 (76.3)	26 (78.8)	0.761
Gene status, n (%)			0.127
KRAS mutation	17 (35.6)	8 (24.2)
KRAS wild type	48 (12.6)	7 (21.2)
Unknown	70 (51.9)	18 (54.5)
Targeted therapy, n (%)
Bevacizumab treated	27 (14.8)	2 (6.1)	0.21
Cetuximab treated	13 (9.6)	3 (9.1)
Other local treatment, n (%)	31 (23)	4 (12.1)	0.169
Repeated times of HAIC, n (%)			0.554
2	29 (21.5)	10 (30.3)
3-4	43 (21.9)	10 (30.3)
> 6	63 (46.7)	13 (39.4)

HAIC: Hepatic arterial infusion chemotherapy.

Table 2 Analyses of survival outcomes by primary tumor location

Subgroup	OS events n (%)	Median OS, mo (95%CI)		Hazard ratio (95%CI)	P-value	PFS events n (%)	Median PFS, mo (95%CI)		Hazard ratio (95%CI)	P-value
		Left-sided	Right-sided				Left-sided	Right-sided
All eligible patients (n = 168)	138 (82.1)	16.3 (13.5-19.0)	9.3 (3.4-15.1)	0.74 (0.48-1.13)	0.164	151 (89.9)	5.7 (5.3-6.1)	4.2 (3.2-5.1)	0.96 (0.64-1.50)	0.851
KRAS wild type (n = 55)	44 (76.4)	17.6 (12.3-22.9)	15.4 (6.0-24.7)	0.85 (0.33-2.19)	0.74	51 (92.7)	5.1 (4.2-5.9)	4.0 (2.7-5.3)	0.76 (0.32-1.81)	0.529
KRAS mutation (n = 25)	18 (72)	10.9 (0-34.6)	9.0 (2.4-15.5)	0.77 (0.29-2.02)	0.6	22 (88)	4.8 (2.9-6.6)	2.1 (0-5.0)	0.97 (0.36-2.58)	0.956
KRAS unknown (n = 88)	78 (88.6)	16.1 (14.1-18.1)	9.3 (6.9-11.7)	0.69 (0.38-1.24)	0.218	78 (88.6)	6.2 (5.1-7.3)	6.0 (3.3-8.7)	0.75 (0.42-1.33)	0.324
Bevacizumab (n = 29)	21 (72.4)	24.5 (16.6-32.3)	9.3 (-)	0.30 (0.06-1.43)	0.11	27 (93.1)	6.2 (4.9-7.4)	4.0 (-)	0.45 (0.10-2.01)	0.285
Cetuximab (n = 16)	12 (75)	16.5 (9.0-23.9)	8.2 (-)	0.21 (0.03-1.29)	0.065	15 (93.8)	3.6 (0.89-6.3)	4.0 (-)	0.42 (0.08-2.06)	0.269

OS: Overall survival; PFS: Progression-free survival.

Table 3 Univariate analysis of predictive factor of survival after first hepatic arterial infusion chemotherapy

Variable	MST (mo)	Univariate analysis		P-value
		HR	95%CI
Primary tumor site (right/left)	9.3 vs 16.3	1.353	0.881-2.079	0.167
Age (> 60/< 60 yr)	16 vs 15.5	1.026	0.731-1.440	0.88
Gender (male/female)	16.5 vs 13	0.744	0.520-1.063	0.104
Histology (poor/well to moderate)	10.3 vs 15.9	1.706	1.003-2.904	0.049*
Serum CA19-9 (≥ 37U/mL/< 37 U/mL)#	12.5 vs 21.2	2.108	1.444-3.076	< 0.001*
Serum CA72-4 (≥ 6.7 U/mL/< 6.7 U/mL)#	13 vs 20.8	1.605	1.114-2.311	0.011*
Serum CEA (≥ 5U/mL/< 5 U/mL)#	14.6 vs 21.1	1.428	0.867-2.351	0.162
Extrahepatic metastasis (present/absent)	15.8 vs 15.8	1.172	0.825-1.667	0.376
Time to liver metastasis (synchronous/ metachronous)	14.8 vs 16.5	1.125	0.802-1.580	0.495
Other local treatment (combined/uncombined)	21.1 vs 14.6	0.651	0.426-0.995	0.047*
Response to HAIC				< 0.001*
PR	21.9	0.234	0.146-0.375	< 0.001*
SD	16.1	0.285	0.185-0.439	< 0.001*
PD	7.5	1	1	NA
Infusion agents (OXA/CPT-11)	15.8 vs 22.8	1.225	0.660-2.273	0.52
Please define what this symbol represents in the table legend below
Please define what this symbol represents in the table legend below

MST: Median survival time; HR: Hazard ratio; HAIC: Hepatic arterial infusion chemotherapy; PR: Partial response; SD: Stable disease; PD: Progressive disease.