KRAS and neoplasm: To determine the sensitivity of the COLD-PCR melting curve assay to detect low quantities of mutant allele in WT background we adopted two complementary strategies: (1) we mixed KRAS-mutant cell line DNA with KRAS-WT peripheral blood leukocyte DNA, and (2) KRAS-mutant FFPE tumor DNA with KRAS-WT FFPE tumor DNA at mutant:WT ratios of 50/50, 20/80, 10/90, 5/95, 2/98, and 1/99.