Skip to main content

Table 2 Clinicopathological, and molecular characteristics according to KRAS mutation status in 1267 colorectal cancer cases

From: Analyses of clinicopathological, molecular, and prognostic associations of KRAS codon 61 and codon 146 mutations in colorectal cancer: cohort study and literature review

Clinicopathological or molecular feature Total No. KRAS P(Wild-type vs. mutant) KRAS mutations identified in only one codon P(Across four mutants)
Wild-type Mutant Codon 12 Codon 13 Codon 61 Codon 146
Total No. of patients 1267 762 505   333 108 17 35  
Sex     0.0091      0.11
 Male 573 (45%) 322 (42%) 251 (50%)   162 (49%) 59 (55%) 4 (24%) 19 (54%)  
 Female 694 (55%) 440 (58%) 254 (50%)   171 (51%) 49 (45%) 13 (76%) 16 (46%)  
Mean age (years) ± SD 68.6 ± 8.7 68.4 ± 8.6 68.8 ± 8.8 0.47 69.5 ± 8.5 67.5 ± 9.2 70.0 ± 9.3 66.0 ± 9.8 0.065
BMI (kg/m2)     0.13      0.43
 <30 1025 (81%) 607 (80%) 418 (83%)   278 (84%) 88 (81%) 11 (69%) 30 (86%)  
 ≥30 240 (19%) 155 (20%) 85 (17%)   54 (16%) 20 (19%) 5 (31%) 5 (14%)  
Year of diagnosis     0.26      0.032
 Prior to 1998 640 (51%) 375 (49%) 265 (52%)   164 (49%) 63 (58%) 5 (29%) 23 (66%)  
 1998 - 2006 627 (49%) 387 (51%) 240 (48%)   169 (51%) 45 (42%) 12 (71%) 12 (34%)  
Family history of colorectal cancer in first degree relative(s)     0.76      0.87
 Absent 1026 (81%) 612 (80%) 414 (82%)   273 (82%) 89 (82%) 14 (82%) 27 (77%)  
 Present in one first degree relative 179 (14%) 111 (15%) 68 (13%)   44 (13%) 15 (14%) 3 (18%) 5 (14%)  
 Present in two or more first degree relatives 62 (5%) 39 (5%) 23 (5%)   16 (5%) 4 (4%) 0 3 (9%)  
Tumor location     <0.0001      0.50
 Cecum 209 (17%) 90 (12%) 119 (24%)   79 (24%) 27 (25%) 4 (24%) 6 (18%)  
 Ascending colon 262 (21%) 171 (23%) 91 (18%)   52 (16%) 25 (24%) 3 (18%) 7 (21%)  
 Hepatic flexure to transverse colon 117 (9%) 78 (10%) 39 (8%)   26 (8%) 7 (6%) 4 (24%) 2 (5%)  
 Splenic flexure to descending colon 90 (7%) 57 (8%) 33 (6%)   22 (7%) 7 (6%) 0 3 (8%)  
 Sigmoid colon 297 (24%) 182 (24%) 115 (23%)   83 (25%) 22 (20%) 1 (5%) 8 (24%)  
 Rectum 279 (22%) 176 (23%) 103 (21%)   67 (20%) 20 (19%) 5 (29%) 8 (24%)  
Disease stage     0.028      0.89
 I 298 (23%) 190 (25%) 108 (21%)   77 (23%) 20 (19%) 4 (23%) 4 (11%)  
 II 354 (28%) 230 (30%) 124 (25%)   77 (23%) 30 (28%) 5 (29%) 11 (32%)  
 III 328 (26%) 183 (24%) 145 (29%)   97 (29%) 29 (27%) 3 (18%) 11 (32%)  
 IV 173 (14%) 93 (12%) 80 (16%)   51 (15%) 18 (16%) 2 (12%) 6 (17%)  
 Unknown 114 (9%) 66 (9%) 48 (9%)   31 (10%) 11 (10%) 3 (18%) 3 (8%)  
Tumor differentiation     <0.0001      0.55
 Well-moderate 1137 (90%) 663 (88%) 474 (94%)   314 (95%) 99 (92%) 16 (94%) 34 (97%)  
 Poor 123 (10%) 94 (12%) 29 (6%)   17 (5%) 9 (8%) 1 (6%) 1 (3%)  
Peritumoral lymphocytic reaction     0.042      0.48
 Absent-minimal 164 (14%) 96 (13%) 68 (14%)   47 (15%) 14 (13%) 2 (12%) 4 (12%)  
 Mild 878 (72%) 515 (71%) 363 (75%)   237 (75%) 76 (71%) 12 (76%) 28 (85%)  
 Moderate-marked 170 (14%) 117 (16%) 53 (11%)   32 (10%) 17 (16%) 2 (12%) 1 (3%)  
MSI status     <0.0001      0.078
 MSI-low/MSS 1057 (85%) 587 (79%) 470 (94%)   315 (95%) 100 (94%) 14 (82%) 31 (89%)  
 MSI-high 191 (15%) 160 (21%) 31 (6.2%)   16 (4.8%) 6 (5.7%) 3 (18%) 4 (11%)  
CIMP status     <0.0001      0.014
 CIMP-negative 521 (44%) 311 (44%) 210 (44%)   139 (44%) 37 (36%) 8 (50%) 19 (54%)  
 CIMP-low 460 (39%) 224 (32%) 236 (49%)   154 (49%) 59 (57%) 4 (25%) 16 (46%)  
 CIMP-high 206 (17%) 172 (24%) 34 (7%)   21 (7%) 7 (7%) 4 (25%) 0  
PIK3CA mutation status     <0.0001      0.63
 Wild-type 983 (84%) 632 (89%) 351 (76%)   242 (78%) 72 (74%) 12 (80%) 19 (68%)  
 Mutant 190 (16%) 78 (11%) 112 (24%)   70 (22%) 25 (26%) 3 (20%) 9 (32%)  
BRAF mutation status     <0.0001      0.25
 Wild-type 1078 (85%) 582 (77%) 496 (99%)   328 (99%) 106 (98%) 16 (94%) 35 (100%)  
 Mutant 184 (15%) 177 (23%) 7 (1%)   3 (1%) 2 (2%) 1 (6%) 0  
Mean LINE-1 methylation level (%) ± SD 62.7 ± 9.3 62.8 ± 9.6 62.5 ± 9.0 0.33 62.7 ± 9.2 61.5 ± 8.2 64.2 ± 10.1 63.1 ± 9.0 0.42
  1. (%) indicates the proportion of cases with a specific clinicopathological, or molecular feature among each KRAS mutation status group. The P-value for significance was adjusted for multiple hypothesis testing to P = 0.05/14 = 0.0036. Thus, a P-value between 0.05 and 0.0036 should be regarded as of borderline significance. BMI, body mass index; CIMP, CpG island methylator phenotype; MSI, microsatellite instability; MSS, microsatellite stable; SD, standard deviation.