188 Background: High-quality end-of-life (EOL) care is a recognized goal for modern cancer care delivery. Illness perception is often inaccurate among patients with cancer and may be associated with the quality of EOL care. We surveyed patients receiving palliative cancer-directed therapies to assess associations between accuracy of perceived likelihood of treatment response and recognized EOL quality measures in a cohort of patients with advanced solid malignancies. Methods: Patients and their oncologists were surveyed regarding perceived benefits of palliative cancer-directed therapies. Accuracy of perception was calculated as patient-assessed minus physician-assessed likelihood of benefit, expressed as a score from -100 to 100, with positive scores indicating that the patient was more optimistic than the oncologist with regards to treatment response. For deceased patients, data on quality of EOL measures, including timing of recent chemotherapy, emergency room (ER) visits, hospitalizations, and intensive care unit (ICU) admissions, hospice enrollment, and location of death were collected. The primary outcome consisted of a composite of ER visit, hospitalization, or ICU admission within 30 days, and/or chemotherapy within 14 days of death. We tested for associations between the unadjusted mean and 95% confidence interval perception of treatment response and EOL metrics. Results: Of 69 patients, median age was 67 years (interquartile range: 61-75), and 50% were male. Cancers included lung (32%), gastrointestinal (22%), genitourinary (16%) and gynecological (16%). Treatments at time of enrollment included cytotoxic chemotherapy (65%), immunotherapy (23%) and oral targeted therapy (12%). Most patients (67%) enrolled in hospice > 7 days prior to death, and 59%, 19%, and 46% were hospitalized, had ICU admission, or an ER visit within 30 days of death, respectively. 12% received cancer-directed systemic therapy in the last 14 days of life. Patients’ accuracy of estimated treatment response was lower for patients with the composite quality outcome, suggesting poorer EOL quality, though this was not statistically significant (20.5, 95% CI: 12.4–28.7 vs. 28.5, 95% CI: 18.0–38.9, p = 0.24). Patients enrolled in hospice > 7 days before death had less accurate perception of treatment benefit (28.1, 95% CI: 20.5–35.8 vs. 13.5, 95% CI: 2.5–24.4, p = 0.03). There was no significant difference for other individual EOL quality measures (all p≥0.17). Conclusions: In this cohort of patients with advanced solid cancer, higher EOL quality measures did not correlate with accuracy of perception of treatment responses. Patients who were more optimistic compared to their treating oncologists were more likely to be enrolled in hospice for > 7 days before death. Improving EOL care for patients with advanced cancer requires more than ensuring accurate patient understanding of treatment goals.