Although KRAS mutations have classically been defined as a negative prognostic factor, with more undifferentiated tumors having unfavorable survival and disease-free survival rates compared to KRAS wild-type (wt) tumors, the role of KRAS as a prognostic factor in NSCLC is not well established at this time due to heterogeneity among studies (14, 15). Here, KRAS is linked to non-small cell lung carcinoma.