S1403, Afatinib Dimaleate With or Without Cetuximab in Treating Patients With Newly Diagnosed Stage IV or Recurrent, EGFR Mutation Positive Non-small Cell Lung Cancer

Inclusion Criteria: * Patients must have histologically or cytologically confirmed stage IV (American Joint Committee on Cancer \[AJCC\] 7th Edition) or recurrent non-small cell lung cancer (NSCLC) * Patients must have documented presence of an EGFR exon 19 deltion or exon 21 (L858R) substitution mutation; T790M mutation or other molecular abnormality will be allowed as long as it accompanies one of the mutations listed above; EGFR testing must be performed using a Food and Drug Administration (FDA)-approved test or in a Clinical Laboratory Improvement Amendments (CLIA)-certified laboratory. * Patients must have tissue available and must agree to submission of tissue and blood; one to two paraffin-embedded tissue blocks or 15-20 unstained slides are requested (a minimum of 12 slides is required); cytology (i.e. fine-needle aspirations, pleural effusion specimens) is acceptable if a cell block or sufficient unstained slides are available; tumor material must be reviewed by a local pathologist who must confirm that at least 100 viable tumor cells are present in the sample and sign the S1403 Pathology Review Form; patients must also be willing to submit blood samples for correlative research at baseline, during treatment and at progression * Patients enrolled at sites participating in the Repeat Biopsy Study must agree to submission of tissue obtained by a repeat biopsy performed at the time of disease progression * Patients must not have received any prior systemic anticancer …