Role of COX-2 in carcinogenesis of colorectal cancer and its relationship with tumor biological characteristics and patients’ prognosis

Table 1 Relationship between COX-2 expression and clinico-pathological factors in colorectal cancer

Item	Total	COX-2 positive	Positive rate (%)	χ2 value	P value
Gender				0.557	0.455
Male	70	61	87.1
Female	69	57	82.6
Tumor location				0.006	0.939
Colon	54	46	85.1
Rectum	85	72	84.7
Gross type				0.330	0.848a
Protruding or fungoid	59	50	84.7
Ulcerative	76	65	85.5
Infiltrative	4	3	75.0
Differentiation				3.917	0.417a
Papillary	3	3	100.0
Well-differentiated	56	49	87.5
Moderately-differentiated	52	42	80.8
Poorly-differentiated	11	8	72.7
Mucinous/signet cell	17	16	94.1
Invasion depth				0.188	0.910
Mucosa to	35	29	82.8
muscularis propria
Serosa or adventitia	60	51	85.0
Extraserosa or	44	38	86.4
extraadventitia
TNM staging				0.985	0.811a
Stage I	32	26	81.3
Stage II	50	43	86.0
Stage III	44	37	84.1
Stage IV	13	12	92.3
Vessel emboli				0.003	0.955
Yes	39	33	84.6
No	100	85	85.0
Lymph node metastasis				0.234	0.628
Yes	53	44	83.0
No	86	74	86.0
Haemotogenous metastasis				1.108	0.292
Yes	40	32	80.0
No	86	75	87.2
Age	57.2 ± 3.1	57.3 ± 1.2	0.962b
Maximal diameter (cm)	4.3 ± 0.3	4.6 ± 2.9	0.599b

^brefers to with t test, others with χ² test or Fisher two side exact test;

^arefers to that more than 25% of the theoretical values were less than 5 and no statistical significance was reached even after the combination.