Late effects in rare cancer registrants.

e20577 Background: Knowledge of late effects in rare cancers could improve care, yet data on these outcomes are sparse. We sought to describe physical and mental health outcomes in a registry of patients diagnosed with rare cancers using 3 established assessment tools. Methods: 321 registrants enrolled in the Rare Cancer Genetics Registry with hematologic (31%), genitourinary (21%), gastrointestinal (18%), sarcoma (15%), head/neck (11%) or gynecologic (4%) cancers completed the assessment. Median time since diagnosis was 3 years; most (69%) were no longer receiving treatment. Four outcomes were assessed, reflecting overall physical and mental health, psychological distress, and loneliness, as measured by the SF-12v2 Health Survey, Brief Symptom Inventory-18, and a three-item loneliness scale, respectively. Linear regression was used to assess the association between outcomes and socio-demographic and cancer-related factors, and the mean score for each outcome was compared to the appropriate reference popu...