Investigator Disclosure and Advanced Cancer Patient Understanding of Informed Consent and Prognosis in Phase I Clinical Trials

Abstract

Purpose: Advanced cancer patients (ACPs) who participate in phase I clinical trials often report a less-than-ideal understanding of the required elements of informed consent (IC) and unrealistic expectations for anticancer benefit and prognosis. We examined phase I clinical trial enrollment discussions and their associations with subsequent ACP understanding.

Methods: Clinical encounters about enrollment in phase I trials between 101 ACPs and 29 oncologists (principal investigators [PIs] and fellows) at three US academic medical institutions were recorded. The Roter Interaction Analysis System was used for analysis. ACPs completed follow-up questionnaires to assess IC recall.

Results: PIs disclosed the following phase I IC elements to ACPs in encounters: trial purpose in 40%; specific physical risks in 60%; potential specific medical benefits gained by trial participation (eg, disease stabilization) in 48.2%; and alternatives to phase I trial participation in 47.1%, with 1.1% of encounters containing palliative and 2.3% hospice information. PIs provided ACP-specific prognoses in 29.0% of encounters but used precise terms of death in only 4.7% and terminal in 1.2%. A significant association existed between PI disclosure of the trial purpose as dosage/toxicity, and ACPs subsequently correctly recalled trial purpose versus PIs who did not disclose it (85% v 13%; P < .05).

Conclusion: Many oncologists provide incomplete disclosures about phase I trials to ACPs. When disclosure of certain elements of IC occurs, it seems to be associated with better recall, especially with regard to the research purpose of phase I trials.