LAUSR

Simple Summary Prolonged survival after treatment of primary central nervous system lymphoma (PCNSL) led to considering patients’ everyday functional needs. Apart from cognitive functions (e.g., memory, attention), which have been investigated previously, social participation affects the quality of life (QoL). Although successful navigation in a social world is crucial for participation, social functioning in PCNSL patients has not been addressed so far. In this study, we investigated social abilities in PCNSL patients with ongoing complete remission for at least one year. PCNSL patients had difficulties in inferring others’ mental states and were impaired in providing optimal solutions for difficult social situations as compared to matched healthy controls. This demonstrates that PCNSL patients differ from healthy controls in their social functioning even in the absence of (residual) disease itself. Social difficulties may represent an additional burden affecting patients’ and caregivers’ QoL. Abstract Within the past decades, long-term survival was achieved in a substantial fraction of primary central nervous system lymphoma (PCNSL) patients, expanding the focus of research to their quality of life (QoL). Social relationships crucially contribute to well-being in the context of adversity. Therefore, abilities that facilitate social interactions essentially determine QoL. The present study specifically targeted those sociocognitive abilities. Forty-three PCNSL patients with ongoing complete remission to therapy for at least one year and 43 healthy controls matched for age, gender and education were examined with standardized self-report and behavioral measures of social cognition. An impaired ability to comprehend others’ feelings was found in patients for both positive and negative mental states. Patients had difficulties in identifying the awkward element in challenging social situations, whereas the degree of discomfort experienced in those situations was comparable between groups. Both the production of optimal solutions for social situations and the mere recognition of these among less optimal strategies were impaired in patients. Clinicians should be aware of possible sociocognitive impairment and ought to address this in additional supportive interventions. Impaired sociocognitive abilities may entail social conflicts at a time when patients rely on social support. This, in turn, could detrimentally affect QoL.