TGF-α and amphiregulin levels in non-small cell lung cancer (NSCLC) patients (pts) treated with erlotinib/placebo in the National Cancer Institute of Canada Clinical Trials Group (NCIC CTG) BR.21

11023 Background: In BR.21, erlotinib prolonged survival of previously treated NSCLC pts. We examined the predictive/ prognostic effects of the EGFR ligands, TGFa and amphiregulin(Am). Methods: Plasma was collected prior to treatment in consenting pts. TGFa and Am were analyzed by ELISA (RD for Am 10 (high). Standard statistical methods were used to correlate biomarker data with baseline characteristics and outcomes. Results: In 731 randomized pts, 539 were evaluable for both markers; there was a significant interaction (p=0.03) between the evaluable and inevaluable cohorts (erlotinib benefit favoring the evaluable cohort); evaluable pts were more likely to be male, > 60 and to have EGFR amplificati...