Approximately 20,000 people per year are diagnosed with cancer in Oregon. The OHSU Knight Cancer Institute is the only academic cancer center in the state, with the nearest center located almost 200 miles away. Clinical trials (CT) are essential for cancer care but only a small proportion of eligible people participate due to multiple factors. In this retrospective study, we identified the association between sociodemographic factors and cancer CT participation at OHSU


Adult patients referred to OHSU for evaluation and treatment of a new cancer 2019- 2022 were included. Data collected included age, gender, race/ethnicity, zipcode, insurance, type of cancer and CT participation. Zip-codes were used to estimate poverty level as defined by the American Community Survey, rural vs. urban location and distance to the cancer center. Multivariate analysis was conducted to identify factors associated with CT participation.


A total of 14,261 patients with median age 65 (18-101) years were treated at OHSU from 2019-2022 (86% for solid tumors, 14% hematologic malignancies). Of these, 53% were > 65yrs, 51% male and 8.5% self-identified as non-White (including Hispanic). These numbers are similar to those reported in the statewide cancer registry. About 61% of those < 65 yrs were privately insured, 84% of those > 65 yrs had Medicare, and 31% were from areas at or below the national poverty level. About 40% lived > 30 miles from OHSU (29% > 60 miles, 14% > 120 miles) and 31.5% lived in rural areas. A total of 2134 patients (15%) participated in cancer CT (8% interventional, 6% interventional therapeutic and 10% noninterventional). Factors independently associated with decreased CT participation on multivariate analysis included age > 65yrs regardless of type of insurance, < 65yrs with public insurance, female, racial/ethnic minority, solid tumor diagnosis and cancer care at a community-based clinic (Table 1).



Patient with cancer treated at OHSU are representative of the population in our catchment area and region. However, there is room to improve access and CT participation for older adults and persons from racial/ethnic minorities and disadvantaged backgrounds. Our study highlights the importance of understanding the catchment area and accounting for social determinants of health when implementing community outreach strategies for CT participation.