The variability seen in the published clinical evidence for the predictive value of the EGFR FISH assay in NSCLC could result from differences between the studies (eg, different patient populations, different study designs and treatment and control arms (TKI monotherapy versus placebo or TKI+chemotherapy versus chemotherapy)), as well as differences in the methodologies used by the various study laboratories for performing and interpreting the assay. Here, EGFR is linked to non-small cell lung carcinoma.