Assessing decisional capacity in patients with brain tumors

Brain tumors can rapidly affect the cognitive function and decisional capacity of patients.1,2 The general lack of effective treatments for brain cancer means that patients must often balance the goal of extending life with substantial treatment burden and side effects—decisions that engage patients' personal preferences. Similarly, these patients are vitally needed for cancer research studies, and in order to participate must have the cognitive capacity to provide informed consent. Thus, the very nature of their illness threatens the capacity of patients with brain tumor to make both treatment and research participation decisions. There is an ethical imperative to ensure that capable patients are supported in their decision-making while incapacitated patients are protected; in either case, an evidence-based approach to determining the patients' capacity is necessary. However, the problem of impaired decisional capacity in brain tumors is underrecognized,3 despite specific evidence showing high rates of incapacity, at least in patients with malignant tumors.1