OBJECTIVES/GOALS: To determine the impact of regional anesthesia (RA) on rates of breast cancer recurrence, breast cancer specific mortality, post mastectomy pain syndrome, and chronic opioid use among patients who received regional anesthesia during primary breast cancer surgery. METHODS/STUDY POPULATION: Study population: Patients who underwent primary breast cancer surgery at Emory University and among a national patient cohort. Methods: This is a retrospective analysis of patients who underwent primary breast cancer surgery. Invasive breast cancer specific survival & breast cancer-specific survival will be estimated using Kaplan-Meier method and compared among patient groups. Cox proportional hazards will be utilized to estimate the unadjusted & adjusted risk of breast cancer recurrence and breast cancer-specific mortality between the two groups. RESULTS/ANTICIPATED RESULTS: We will present on our work comparing rates of breast cancer recurrence among patients who received regional anesthesia compared to patients who did not. DISCUSSION/SIGNIFICANCE: This study aims to establish the effect of regional anesthesia on breast cancer recurrence,breast cancer specific mortality, post mastectomy pain syndrome, and chronic opioid use following primary breast cancer surgery.