Table 1

Distribution of MSI statusa in colon tumors by age and sex

AgeControls n (%)MSI+ n (%)MSI− n (%)OR (95% CI)χ2Pb MSI+ vs. MSI−Interaction Pc for age and sex
Men
<50131 (10.2)16 (13.3)53 (7.6)1.0
51–64414 (32.1)34 (28.3)242 (34.5)0.5 (0.2–0.9)
65–79745 (57.7)70 (58.3)406 (57.9)0.5 (0.3–1.0)0.07
Women
<5098 (8.7)10 (6.9)45 (8.3)0.8 (0.3–1.9)
51–64346 (30.9)38 (26.0)211 (38.9)0.6 (0.3–1.2)
65–79676 (60.4)98 (67.1)287 (52.8)1.2 (0.7–2.3)<0.01<0.01
  • a MSI determined by 30% or more of 10 tetranucleotide markers unstable, BAT26 unstable, or TGFBRII unstable.

  • b χ2 Ps are for difference in proportion of MSI+ vs. MSI− tumors by age in men and in women separately.

  • c The P shows the interaction between gender and age as a risk factor for an MSI+ tumor.