Table 1.

Risk factor characteristics of the subset of participants evaluated for Ki-ras mutations and p53 protein overexpression compared with that of the Wheat Bran Fiber clinical trial population

CharacteristicsSubset with Ki-ras mutation and/or p53 expression data (N = 926)Wheat Bran Fiber trial participants (N = 1,429)
Age (mean ± SD)65.3 ± 9.065.7 ± 9.0
Gender, n (%)
    Female300 (32.4)480 (33.6)
    Male626 (67.6)949 (66.4)
Family history*
    No770 (83.2)1,189 (83.2)
    Yes156 (16.8)240 (16.8)
Previous polyp
    No825 (62.6)784 (61.9)
    Yes316 (37.4)482 (38.1)
No. of adenomas at baseline
    1526 (56.8)815 (57.0)
    >1400 (43.2)614 (43.0)
Adenoma location
    Distal colon327 (35.4)503 (35.3)
    Proximal colon243 (26.3)387 (27.2)
    Rectum133 (14.4)209 (14.7)
Adenoma size (cm)
    <1525 (56.8)858 (60.3)
    ≥1399 (43.2)566 (39.8)
Degree of dysplasia
    Low grade639 (71.6)992 (75.0)
    High grade254 (28.4)330 (25.0)
Histology
    Tubular526 (57.2)863 (61.4)
    Tubulovillous384 (41.8)528 (37.6)
    Villous9 (1.0)14 (1.0)
    Tubulovillous or villous393 (42.8)542 (38.6)
Advanced adenoma
    No362 (39.1)633 (44.3)
    Yes564 (60.9)796 (55.7)
  • * History of colorectal cancer in one or more first-degree relatives.

  • Self-reported history of a polyp prior to baseline adenoma.

  • Includes one or more of the following characteristics: tubulovillous or villous histology, ≥1 cm in size, or HGD.