Some non-small-cell lung cancers (NSCLC) have a mutation in a gene that makes a protein called EGFR. This particular cancer can be treated with certain drugs such as Erlotinib (Tarceva), Gefitinib (Iressa) and Osimertinib (Tagrisso). But many tumors become resistant to these drugs because of a second mutation. Researchers want to test if adding local ablative therapy (LAT) extends the benefits of the drug, Osimertinib. LAT can include techniques such as surgery, radiofrequency ablation, cryotherapy or radiation therapy.