Background: Routine imaging ("scan") results contain key prognostic information for advanced cancer patients. Yet, little is known about how accurately patients understand this information, and whether psychological states relate to accurate understanding. Objective: To determine if patients' sadness and anxiety, as well as results showing poorer prognosis, are associated with patients' understanding of scan results. Design: Archival contrasts performed on multi-institutional cohort study data. Subjects: Advanced cancer patients whose disease progressed after at least one chemotherapy regimen (N = 94) and their clinicians (N = 28) were recruited before an oncology appointment to discuss routine scan results. Measurements: In preappointment structured interviews, patients rated sadness and anxiety about their cancer. Following the appointment, patients and clinicians reported whether the imaging results discussed showed progressive, improved, or stable disease. Results: Overall, 68% of patients reported their imaging results accurately, as indicated by concordance with their clinician's rating. Accuracy was higher among patients whose results indicated improved (adjusted odds ratio [AOR] = 4.12, p = 0.02) or stable (AOR = 2.59, p = 0.04) disease compared with progressive disease. Patients with greater anxiety were less likely to report their imaging results accurately than those with less anxiety (AOR = 0.09, p = 0.003); in contrast, those with greater sadness were more likely to report their results accurately than those with less sadness (AOR = 5.23, p = 0.03). Conclusions: Advanced cancer patients with higher anxiety and those with disease progression may need more help understanding or accepting their scan results than others.