Table 3.
Patient demographics and characteristics of colorectal cancers evaluated for BRAF mutations
| Characteristic | All patients (n = 145) | Patients with BRAF mutation (n = 42) | Patients without BRAF mutation (n = 103) | p Value* |
| Age at operation (y) (mean (SE)) | 65.6 (1.3) | 73.5 (2.2) | 62.3 (1.4) | <0.0001 |
| Sex | 0.006 | |||
| Male | 76 (52%) | 14 (33%) | 62 (60%) | |
| Female | 69 (48%) | 28 (67%) | 41 (40%) | |
| Site relative to splenic flexure | <0.0001 | |||
| Right sided | 75 (52%) | 35 (85%) | 40 (39%) | |
| Left sided | 68 (48%) | 6 (15%) | 62 (61%) | |
| Unknown | 2 | 1 | 1 | |
| Family history | 0.002 | |||
| Yes (HNPCC) | 18 (12%) | 0 (0%) | 18 (17%) | |
| No (sporadic) | 127 (88%) | 42 (100%) | 85 (83%) | |
| Histological grade | <0.0001 | |||
| Well differentiated | 2 (1%) | 0 (0%) | 2 (2%) | |
| Moderately differentiated | 87 (60%) | 15 (36%) | 72 (70%) | |
| Poorly differentiated | 51 (35%) | 26 (61%) | 25 (24%) | |
| Unknown | 5 | 1 | 4 | |
| Mucinous histology | <0.0001 | |||
| Present | 33 (33%) | 22 (61%) | 11 (17%) | |
| Absent | 67 (67%) | 14 (39%) | 53 (83%) | |
| Tumour infiltrating lymphocytes | 0.38 | |||
| Numerous | 14 (12%) | 9 (26%) | 5 (6%) | |
| Mild infiltration | 32 (28%) | 14 (41%) | 20 (23%) | |
| No infiltration | 72 (60%) | 11 (33%) | 61 (71%) | |
| Clinicopathological stage† | 0.68 | |||
| I | 22 (15%) | 6 (14%) | 16 (16%) | |
| II | 72 (50%) | 23 (55%) | 49 (48%) | |
| III | 41 (28%) | 11 (26%) | 30 (29%) | |
| IV | 8 (6%) | 1 (2%) | 7 (7%) |
HNPCC, hereditary non-polyposis colorectal cancer.
*We used either Pearson’s χ2 test or Fisher’s exact test where appropriate to compare all variables except mean age at operation, for which we used an unpaired t test.
†Clinicopathological stage was classified according to the criteria of UICC-TNM classification.34