Background: ASCO Quality Oncology Practice Initiative (QOPI) encourages hospitals to determine if patients (pts) with stage IV NSCLC adenocarcinoma have activating EGFR mutations. Guidelines recommend tumor testing to identify ALK, BRAF, EGFR, ROS1 and other gene alterations before treatment. Studies have shown EGFR testing underutilization. We developed and tested a tool to identify EGFR tests in Veterans Affairs (VA) electronic health record (EHR). We examined whether Veterans with newly diagnosed NSCLC-IV underwent EGFR testing. We measured EGFR testing trends and analyzed differences by patient, VA Medical Center (VAMC) and region. Methods: VA EHR data identified Veterans with NSCLC-IV diagnosed 2013-2017, who survived 45+ days and had 2+ visits with a VA oncologist within 120 days of diagnosis. All NSCLC histologies were included. Demographics and VAMC were obtained from VA Corporate Data Warehouse. EGFR testing results performed outside VA were from commercial laboratory data. We deployed a natural language processing (NLP) tool to identify EGFR tests in VA EHR clinical notes. Testing rates and characteristics associated with testing were examined by descriptive analysis. Results: Of 3484 pts, 623 (18%) had evidence of EGFR testing. There was a 244% rise in testing. 54 (9%) pts diagnosed in 2013 were tested vs 186 (25%) diagnosed in 2017 (χ² 82.3, p-value 0.00). No statistically significant differences by sex, race, or urban/rural address existed. Testing decreased as pts aged (χ² 27, p-value 0.00). 35% of pts age ≤49 and 12% of pts age ≥80 were tested. Testing varied widely by VAMC and region (VAMC χ² 795.6, p-value 0.00; region χ² 90.3, p-value 0.00). 28% of pts in the Pacific were tested vs 10% of pts in the Southeast. The main contributor to regional variation was VAMC differences. VAMCs that conducted EGFR testing within their own laboratories (64% and 53%), or were co-located with the national precision oncology program (NPOP, 59%) tested the most pts. NPOP was temporally associated with increased testing nationally. 9% of pts diagnosed in 2017 were tested using NPOP. Conclusions:EGFR testing underutilization in the VA persists. QOPI and the NLP tool for this initiative will help system-wide quality improvement initiatives.