Table 1.

The characteristics of patients.

	All patients
Variable	Total	Right-side colon	Left-side colon	Rectum	P-value, chi-square
Number of patients	984	300	345	339
Age
≤50 y	387	120	138	129	0.934
51-65 y	387	120	131	136
>65 y	210	60	76	74
Gender
Male	637	177	228	203	0.036
Female	347	123	117	107
Mucinous histology
Yes	158	69	49	40	<0.001
No	826	231	296	299
Stage at diagnosis
I	8	1	2	5	<0.001
II	70	20	20	30
III	206	48	56	102
IV	700	231	267	202
First line therapy
Chemotherapy	740	222	259	259	0.685
Bevacizumab + chemotherapy	244	78	86	80
Metastatic organ
1	714	221	251	242	0.808
>1	270	79	94	97
CEA
≤5 ng/ml	275	81	92	102	0.563
>5 ng/ml	702	217	250	235
unknown	7	2	3	2
LDH
≤245 U/ml	702	228	230	244	0.035
>245 U/ml	279	71	113	95
unknown	3	1	2
Backbone chemotherapy
Oxaliplatin-based	682	213	244	225	0.685
Irinotecan-based	257	73	87	97
5-fluorouracil only	45	14	14	17
Bevacizumab beyond first line
Yes	83	26	31	26	0.813
No	901	274	314	313
Cetuximab treated
Yes	104	29	40	35	0.637
No	880	271	304	304
Primary tumor resection
Yes	606	186	220	200	0.432
No	378	114	125	139