Table 4.
Association between the type of Ki-ras mutation and selected demographic and clinicopathologic characteristics
| No. of subjects | Mutation | Affected codon | ||||||
|---|---|---|---|---|---|---|---|---|
| No Ki-ras mutation, no. (%) | Ki-ras mutation, no. (%) | G-to-A transition, n (%) | G-to-T transversion, no. (%) | G-to-C transversion, no. (%) | Codon 12, no. (%) | Codon 13, no. (%) | ||
| Age (y) | ||||||||
| <66 | 389 | 349 (89.7) | 40 (10.3) | 18 (4.6) | 20 (5.1) | 2 (0.5) | 31 (8.0) | 9 (2.3) |
| ≥66 | 509 | 417 (81.9) | 92 (18.1) | 47 (9.2) | 39 (7.7) | 9 (1.8) | 80 (15.7) | 16 (3.1) |
| P * | 0.001 | 0.01 | 0.12 | 0.08 | 0.0005 | 0.34 | ||
| Adenoma location | ||||||||
| Proximal colon | 293 | 261 (89.1) | 32 (10.9) | 18 (6.1) | 11 (3.8) | 3 (1.0) | 28 (9.6) | 5 (1.7) |
| Distal colon | 437 | 377 (86.3) | 60 (13.7) | 28 (6.4) | 27 (6.2) | 6 (1.4) | 48 (11.0) | 12 (2.8) |
| Rectum | 84 | 65 (77.4) | 19 (22.6) | 7 (8.3) | 11 (13.1) | 0 (0.0) | 17 (20.2) | 2 (2.4) |
| P | 0.03 | 0.59 | 0.0085 | 0.79 | 0.03 | 0.64 | ||
| Histology | ||||||||
| Tubular | 657 | 604 (91.9) | 53 (8.1) | 23 (3.5) | 23 (3.5) | 6 (0.9) | 45 (6.9) | 9 (1.4) |
| Tubulovillous | 208 | 142 (68.3) | 66 (31.7) | 33 (15.9) | 31 (14.9) | 5 (2.4) | 56 (26.9) | 12 (5.8) |
| Villous | 30 | 18 (60.0) | 12 (40.0) | 9 (30.0) | 4 (13.3) | 0 (0.0) | 9 (30.0) | 4 (13.3) |
| P | <0.0001 | <0.0001 | <0.0001 | 0.10 | <0.0001 | <0.0001 | ||
| Adenoma size (cm) | ||||||||
| <1 | 547 | 491 (89.8) | 56 (10.2) | 25 (4.6) | 27 (4.9) | 5 (0.9) | 47 (8.6) | 10 (1.8) |
| ≥1 | 349 | 274 (78.5) | 75 (21.5) | 39 (11.2) | 32 (9.2) | 6 (1.7) | 63 (18.1) | 15 (4.3) |
| P | <0.0001 | <0.0001 | 0.005 | 0.22 | <0.0001 | 0.01 | ||
| Dysplasia | ||||||||
| Low grade | 675 | 601 (89.0) | 74 (11.0) | 34 (5.0) | 33 (4.9) | 9 (1.3) | 59 (8.7) | 16 (2.4) |
| High grade | 210 | 157 (74.8) | 53 (25.2) | 29 (13.8) | 23 (11.0) | 2 (1.0) | 47 (22.4) | 9 (4.3) |
| P | <0.0001 | <0.0001 | 0.0004 | 1.00 | <0.0001 | 0.07 | ||
| Advanced adenoma† | ||||||||
| No | 429 | 401 (93.5) | 28 (6.5) | 11 (2.6) | 10 (2.9) | 3 (0.7) | 25 (5.8) | 3 (0.7) |
| Yes | 469 | 365 (77.8) | 104 (22.2) | 54 (11.5) | 41 (10.1) | 8 (1.7) | 86 (18.3) | 22 (1.7) |
| P | <0.0001 | <0.0001 | <0.0001 | 0.13 | <0.0001 | <0.0001 | ||
NOTE: Missing data for location and histology (3), missing data for size (2), and missing data for dysplasia (13).
*
Compared with Ki-ras mutation negative based on a Fisher's exact test.
†
Includes one or more of the following characteristics: tubulovillous or villous histology, ≥1 cm in size, or HGD.