9515 Background: Accurate understanding of prognosis among terminally-ill patients impacts decision-making at the end of life. The goal of this study was to explore illness understanding in patients with advanced non-small cell lung cancer (NSCLC). Methods: As part of a larger randomized study of integrated versus standard palliative care in an ambulatory thoracic oncology clinic, we recruited 120 patients within eight weeks of diagnosis of incurable NSCLC with a performance status of 0–2. Prior to randomization, patients completed questionnaires on quality of life (FACT-L) and mood (HADS), as well as the following items regarding illness understanding: 1) “My cancer is curable” (yes/no); “The goals of my therapy are: to help me live longer” (yes/no), “try to make me feel better” (yes/no), “to get rid of all my cancer” (yes/no); and 3) “My current health status is: relatively healthy, seriously but not terminally ill, or seriously and terminally ill”). Results: Approximately one third of patients (n=39/116, 33.6%) believed their cancer to be curable. While most patients felt that the goals of therapy were to help them live longer (n=110/113, 97.3%) and feel better (n=102/102, 100%), 66.0% (n=64/97) also believed that getting rid of all of the cancer was a treatment goal. Only 13.9% (n=16/115) of patients believed that their current health status was seriously and terminally ill. Patients who reported greater depression and anxiety symptoms on the HADS were more likely than those without such distress to believe that their cancer was curable (OR=2.47, p=.03) and that one of the goals of treatment was to get rid of all of their cancer (OR=3.83, p=.02). Conclusions: Despite having an incurable illness, the majority of patients with advanced NSCLC do not view themselves as terminally ill or have an accurate understanding of the goals of anti-cancer therapy. Given that patients often make treatment decisions based on their prognostic awareness, many of these individuals, particularly those with comorbid mood symptoms, may be at risk of pursuing unsuitable choices for their care. Interventions are needed to promote greater understanding of prognosis and goals of therapy in this population. No significant financial relationships to disclose.