Table 3. Clinicopathological and molecular characteristics of the KRAS- and BRAF- mutant TSAs.
| BRAF mutant TSA | KRAS mutant TSA | p value | |
|---|---|---|---|
| No. of cases | 24 | 11 | |
| Sex (male/female) | 16/8 | 9/2 | 0.45 |
| Age (y, mean ± SD) | 65.9 ± 8.7 | 63.1 ± 15.9 | 0.61 |
| Tumor location, n (bowel subsite) | |||
| Proximal (C/A/T) | 9 (1/7/1) | 1 (0/0/1) | 0.12 |
| Distal (D/S/R) | 15 (2/9/4) | 10 (0/4/6) | |
| Tumor size (mm, mean ± SD) | 11.9 ± 4.5 | 12.1 ± 5.9 | 0.92 |
| Morphology, n (%) | |||
| 0-Ip | 10 (42) | 3 (27) | 0.26 |
| 0-Is | 12 (50) | 5 (46) | |
| 0-IIa | 2 (8) | 3 (27) | |
| Gene mutation/epigenetic alteration, n (%) | |||
| RNF43 mutation | 13 (54) | 0 (0) | < 0.01 |
| APC mutation | 4 (17) | 3 (27) | 0.65 |
| WNT signaling associated genes | 17 (71) | 6 (55) | 0.35 |
| CIMP | 12 (50) | 3 (27) | 0.28 |
| CIMP-high | 9 (38) | 0 (0) | 0.03 |
| SMOC1 methylation | 9 (38) | 9 (82) | 0.03 |
TSA, traditional serrated adenoma; C, cecum; A, ascending colon; T, transverse colon; D, descending colon; S, sigmoid colon; R, rectum; CIMP, CpG island methylator phenotype