Table 4.

KRAS/BRAF/APC mutations, lack of expression of MGMT, and age at diagnosis

Somatic alteration≤50 y (%)>50 y (%)P
KRAS mutations5/27 (18.5)18/30 (60.0)0.001
    G > A4/510/18
    G > T1/55/18
    G > C0/53/18
BRAF mutations2/27 (7.4)0/30Not significant
KRAS/BRAF7/27 (26.0)18/30 (60.0)0.009
APC mutations*4/25 (16.0)6/27 (22.0)Not significant
MGMT abrogation0/228/22 (36.4)0.001
  • * APC mutation analysis was not done in 5 out of 57 samples due to shortage of tumoral DNA.

  • Reliable immunohistochemical data regarding MGMT protein expression was obtained in 44 out of 57 tumors.

  • Fisher's exact test.