Prognostic value of preoperative carcinoembryonic antigen/tumor size in rectal cancer

Table 1 Association of carcinoembryonic antigen/tumor size with baseline characteristics of rectal cancer patients n (%)

	Training cohort (n = 371)				Validation cohort (n = 185)
	Cases	Low	High	P-value	Cases	Low	High	P-value
Age	371	58 (21-89)	65 (32-86)	< 0.001a	185	61 (25-87)	57 (35-79)	0.149
Tumor size	371	4.3 (0.8-13)	4.3 (0.8-13.5)	0.773	185	4.5 (1-13)	4.3 (0.8-10)	0.472
Sex				0.419				0.199
Male	218	177 (58)	41 (64)		103	82 (53)	21 (68)
Female	153	130 (42)	23 (36)		82	72 (47)	10 (32)
TNM stage				0.008a				0.350
I	104	96 (31)	8 (12)		48	43 (28)	5 (16)
II	127	99 (32)	28 (44)		74	61 (40)	13 (42)
III	140	112 (36)	28 (44)		63	50 (32)	13 (42)
Differentiation				0.395				0.826
Poor	60	51 (17)	9 (14)		24	19 (12)	5 (16)
Moderate	209	176 (57)	33 (52)		102	85 (55)	17 (55)
High	102	80 (26)	22 (34)		59	50 (32)	9 (29)
Lymphovascular invasion				0.697				0.683
Negative	338	281 (92)	57 (89)		173	143 (93)	30 (97)
Positive	33	26 (8)	7 (11)		12	11 (7)	1 (3)
Perineural invasion				0.039a				0.073
Negative	340	286 (93)	54 (84)		172	146 (95)	26 (84)
Positive	31	21 (7)	10 (16)		13	8 (5)	5 (16)
CEA				< 0.001a				< 0.001a
0-5 ng/mL	263	262 (85)	1 (2)		127	126 (82)	1 (3)
> 5 ng/mL	108	45 (15)	63 (98)		58	28 (18)	30 (97)
CA 19-9				0.006a				0.027a
0-37 ng/mL	325	276 (90)	49 (77)		158	136 (88)	22 (71)
> 37 ng/mL	46	31 (10)	15 (23)		27	18 (12)	9 (29)

^aP < 0.05; CEA: Carcinoembryonic antigen; CA 19-9: Carbohydrate antigen 19-9.