Of the 22 excluded cases, 13 were due to unknown EGFR mutation status, 5 were due to less than 3 months of treatment or less than 3 months of follow-up, 2 due to ECOG score greater than 2, 1 due to squamous cell carcinoma, and 1 due to combined thyroid cancer. This evidence concerns the gene EGFR and squamous cell carcinoma.