Table 1

Gene mutations and clinicopathological features in sporadic colorectal adenocarcinomas without microsatellite instability

No. of casesFrequency (%) of alterationsa in the following:
APCK-rasDCCTP53
Overall series8875.050.060.256.8
Age
 ≤60 yr2576.052.060.060.0
 >60 yr6374.649.260.355.5
Gender
 Female3677.761.150.058.3
 Male5273.042.367.355.7
Location
 Proximal colon3177.461.3b64.558.0
 Distal colon3073.353.360.053.3
 Rectum2774.033.355.559.2
Tumor size (cm)
 ≤31478.564.250.050.0
 3.1–65675.048.257.158.9
 >61471.442.878.564.2
Grade
 Well/moderate7876.948.761.560.2
 Poor862.550.037.525.0
Stagec
 A875.050.050.050.0
 B2272.750.072.768.1
 C2470.829.158.354.1
 D3479.464.755.852.9
  • a APC (exon 15); K-ras (exons 1, 2); DCC (loss of heterozygosity in D18S478, D18S1102, D18S474, D18S64, D18S68, D18S61, D18S1161, D18S462, D18S70); TP53 (exons 5–8).

  • b P = 0.09; proximal colon versus rectum, P = 0.033; distal colon versus rectum, P = 0.12; colon versus rectum, P = 0.037.

  • c Stage, modified Dukes’ classification.