BACKGROUND: Patients with advanced cancer who misunderstand their prognosis and chance of cure tend to overestimate the likely benefits of palliative systemic therapy. AIM: To determine patient perceptions of palliative systemic therapy benefits in advanced cancer. METHODS: We surveyed 104 outpatients with advanced cancer receiving systemic anticancer therapy and their treating oncologists. Patients recorded their understanding of treatment impact on chance of cure and symptoms. Life expectancy was estimated by patients and oncologists. A visual analogue scale (0-10) was used to record how patients and oncologists valued quality of life (QOL) and length of life (LOL) (<4 QOL most important; 4-7 QOL and LOL equal; >7 LOL most important). Patient-oncologist discordance was defined as a ≥4-point difference. RESULTS: The main reasons patients selected for receiving treatment were to live longer (54%) and cure their cancer (36%). Most patients reported treatment was very/somewhat likely to prolong life (84%) and improve symptoms (76%), whereas 20% reported treatment was very/somewhat likely to cure their cancer. 42% of patients selected a timeframe for life expectancy (choice of four timeframes between <1 year and ≥5 years); of these, 62% selected a longer timeframe than their oncologist. When making treatment decisions, 71% of patients (52% of oncologists) valued QOL and LOL equally. Patient-oncologist discordance was 21%, mostly because of oncologists valuing QOL more than their patients (70%). CONCLUSION: At least 20% of patients receiving systemic therapy for advanced cancer reported an expectation of cure. Most patients and oncologists value QOL and LOL equally when making treatment decisions.