In several previous data sets using tissue-based assays, fusions in patients with CRC were associated with MSI-H cancers.9-12 Although rates of MSI-H and right-sided tumors in our data set were similar to average rates reported in advanced CRCs, a proportion of the fusion-positive patients in this series are suspected to have acquired the fusion after selective pressure from anti-EGFR therapy, and therefore the fusion may have been present in the primary tumor at levels too low to be associated with MSI-H status. The gene discussed is EGFR; the disease is colorectal carcinoma.