Table 2.

Clinicopathologic and molecular features

VariableAfrican Americans,* n = 137 (%)Caucasians, n= 236 (%)χ2 P
Age group (y)
    <6556 (41)102 (43)0.66
    ≥6581 (59)134 (57)
Gender
    Female60 (44)86 (36)0.16
    Male77 (56)150 (64)
Tumor location
    Proximal colon80 (58)101 (43)0.005
    Distal colon41 (30)79 (34)
    Rectum16 (12)55 (23)
Depth of tumor invasion
    pTx01 (<1)0.79
    pT14 (2)6 (3)
    pT220 (15)42 (18)
    pT386 (63)135 (58)
    pT427 (20)50 (21)
Nodal status
    Nx01 (<1)0.64
    N073 (53)131 (56)
    N1-364 (47)102 (44)
Distant metastasis
    M0118 (86)203 (87)0.86
    M119 (14)31 (13)
Tumor stage
    I17 (12)33 (14)0.96
    II53 (39)92 (39)
    III48 (35)78 (34)
    IV19 (14)31 (13)
Tumor grade
    Low103 (76)179 (78)0.65
    High33 (24)51 (22)
Tumor size (cm)
    ≤573 (53)132 (59)0.48
    >562 (47)96 (41)
p53 status
    Wild-type69 (50)109 (46)0.44
    Mutated68 (50)127 (54)
p53 mutation type
    Disruptive31 (46)51 (40)0.46
    Nondisruptive37 (54)76 (60)
p53 codon 72 phenotypes
    Arg/Arg26 (19)85 (36)0.002
    Arg/Pro87 (64)134 (57)
    Pro/Pro24 (17)17 (7)
Vital status at the end of follow-up§
    Alive36 (28)64 (29)0.98
    Died due to CRC61 (48)104 (47)
    Died due to other causes31 (24)52 (24)
  • Abbreviations: n, total number of cases; CRC, colorectal cancer.

  • * Information on tumor grade for one case and tumor size for two cases was not available for African Americans.

  • Information on tumor location for one case; pT, pN and M for two cases; tumor stage for two cases; tumor grade for six cases; and tumor size for eight cases was not available for Caucasians.

  • p53 mutation that introduces an amino acid that disrupts functional domains of p53.

  • § As described in Materials & Methods, 9 African American and 16 Caucasian patients were lost to follow-up.