Local therapy as a treatment strategy in EGFR-mutant advanced lung cancers that have developed acquired resistance to EGFR tyrosine kinase inhibitors.

7527 Background: The utility of EGFR directed therapy for the treatment of EGFR mutant lung cancer is limited by the development of acquired resistance (AR) to EGFR tyrosine kinase inhibitor (TKI) therapy, which occurs after a median of 16 months (mos). There are no approved targeted therapies after disease progression on EGFR TKI therapy. Local therapy for oligometastatic disease is used with regularity in other solid tumors, and can lead to long term survival in selected individuals. EGFR mutant lung cancers with AR to TKI therapy can follow an indolent course that is amenable to local therapy to treat progression of disease when used in conjunction with continued EGFR inhibition. Outcomes following local therapy in this setting have not been assessed. Methods: Patients (pts) with AR to EGFR TKI’s who received local therapy excluding treatment of CNS metastases or local therapy prior to AR were identified in an IRB-approved prospective registry of 184 pts with AR enrolled from August 2004- November 2011...