Examples include the upfront resistance to anti‐EGFR therapies in metastatic colorectal cancer (CRC) with KRAS MAFs as low as 1% (Azuara et al., 2016; Laurent‐Puig et al., 2015), or the positive association between higher EGFRL858R MAFs in lung cancer specimens and longer duration of treatment benefit with gefitinib and erlotinib in the metastatic setting (Ono et al., 2014; Zhou et al., 2011). Here, KRAS is linked to lung carcinoma.