Table 1 Correlations between RDW and main clinicopathological variables for the 591 patients under study.

Age

<0.001

<0.001

≤67.5 years

296

14.7 (±2.8)

119 (40.2%)

>67.5 years

295

15.7 (±3.4)

164 (55.6%)

Gender

0.821

0.108

Male

349

15.2 (±2.9)

175 (50.1%)

Female

242

15.2 (±3.5)

108 (44.6%)

Tumor location

<0.001

0.012

Colon

444

15.5 (±3.4)

225 (50.7%)

Rectum

147

14.3 (±1.9)

58 (39.5%)

Intent of surgery

0.286

0.001

R0 resection

504

15.3 (±3.2)

21 (19.3%)

R1-2/No resection

87

14.9 (±2.8)

42 (48.3%)

Depth of invasion (pT)

0.017

0.037

pTis

62

14.4 (±2.2)

26 (41.9%)

pT1

91

14.9 (±2.8)

42 (46.2%)

pT2

69

14.7 (±2.8)

25 (36.2%)

pT3

227

15.5 (±3.3)

116 (51.1%)

pT4

137

15.7 (±3.6)

75 (54.7%)

Nodal involvement (pN)

0.856

0.332

pN0

350

15.3 (±3.4)

160 (45.7%)

pN1

152

15.1 (±2.8)

77 (50.7%)

pN2

84

15.3 (±2.9)

45 (53.6%)

Systemic metastasis (M)

0.243

0.212

M0

472

15.3 (±3.4)

225 (47.7%%)

M1a

84

15 (±2.2)

46 (54.8%)

M1b

30

14.4 (±2.1)

11 (36.7%)

TNM stage

0.002

0.049

Stage 0-I

175

14.7 (±2.8)

69 (39.4%)

Stage II

155

15.9 (±4)

80 (51.6%)

Stage III

142

15.5 (±3.2)

76 (53.5%)

Stage IV

114

14.8 (±2.2)

57 (50%)

Histological type

0.594

0.267

Adenocarcinoma

495

15.2 (±3.3)

230 (46.5%)

Mucinous

82

15.5 (±2.8)

46 (56.1%)

Others

14

14.8 (±1.8)

7 (50%)

Tumor grading

0.839

0.134

G1-G2

533

15.4 (±3.6)

217 (48.8%)

G3

58

15.5 (±3.1)

28 (58.3%)