e20038 Background: Regional variation is common in oncology care but is not defined for emergency department (ED) care for cancer patients, particularly patients with lung cancer (LC) who regularly utilize EDs for management of acute cancer or treatment related illness. This study analyzed regional variation and other factors associated with high total episodic charge (≥75th percentile; HTC) among LC patients evaluated in the ED in relation to discharge or admission. Methods: A retrospective study of LC-related ED visits in the US was conducted using the 2013 Nationwide ED Sample. LC-related ED visits among adults were identified by LC-specific Clinical Classification Software codes (CCS = 19; mapping to ICD-9 = 162.x, 209.21, 231.2, V10.11). Multivariable logistic regression analyzed the association between patient and hospital factors and HTC, weighted to represent ED visits nationwide. Results: Among 373,761 LC-related ED visits, 134,838 (36%) were treated and discharged and 238,923 (64%) were admitted (ranging from 51% (West [W]) to 76% (South [S]). HTC was ≥$5,655 (median = $2,993) for ED discharges and ≥$54,760 (median = $29,590) for admissions. The proportion of visits with HTC differed by region and admission status (discharged: 7% [W] to 27% [S]; admitted: 20% [Midwest] to 39% [W]). After adjusting for clinical and hospital factors associated with increased HTC odds (metastases, common acute comorbid disorder [chest and abdominal pain, pneumonia, sepsis, respiratory failure], diagnostic radiology use, thoracic/other surgery, chemo/radiotherapy, length of stay, primary payer, and hospital ownership, location and teaching status), significant HTC variation remained by hospital region with opposing relative HTC odds among discharged and admitted patients (discharged: W v S OR = 0.3 95%CI = 0.2-0.6, Northeast v S OR = 0.5 95%CI = 0.3-0.7; admitted: W v S OR = 3.8 95%CI = 2.5-5.7). Conclusions: Regional variation in HTC suggest differences in ED use and management patterns for LC and may reflect quality of care concerns. Clinical outcome linkage (including ED revisit tracking) is needed to better define the impact of variation and develop strategies to improve care for patients with LC.