Barriers to participation in cancer prevention clinical trials

Background. Cancer prevention clinical trials seek to enroll individuals at increased risk for cancer. Little is known about attitudes among physicians and at-risk individuals towards cancer prevention clinical trials. We sought to characterize barriers to prevention trial participation among medical oncologists and first-degree relatives of their patients. Methods. Physician participants were practicing oncologists in Pennsylvania. Eligible first-degree participants were adult relatives of a cancer patient being treated by one of the study physicians. The influence of perceived psychosocial and practical barriers on level of willingness to participate in cancer prevention clinical trials was investigated. Results. Response rate was low among physicians, 137/478 (29%), and modest among eligible first-degree relatives, 82/129 (64%). Lack of access to an eligible population for prevention clinical trials was the most commonly cited barrier to prevention clinical trials among oncologists. Nearly half (45%) of first-degree relatives had not heard of cancer prevention clinical trials, but 68% expressed interest in learning more, and 55% expressed willingness to participate. In the proportional odds model, greater information source seeking/responsiveness (i.e., interest in learning more about clinical prevention trials from more information sources) (p = 0.04), and having fewer psychosocial barriers (p = 0.02) were associated with a greater willingness to participate. Conclusions. Many individuals who may be at greater risk for developing cancer because of having a first-degree relative with cancer are unaware of the availability of clinical cancer prevention trials. Nonetheless, many perceive low personal risk associated with these studies, and are interested in learning more.