KRAS and colorectal carcinoma: Genomic analyses of pre- and post-treatment samples from patients—including those with non-small cell lung cancer, CRC, and appendiceal cancer—revealed secondary KRAS mutations (such as G12D/R/V/W, G13D, Q61H, R68S, H95D/Q/R, or Y96C) and KRAS amplification as contributors to resistance.