Study protocol for the OPTion randomised controlled trial on the effect of prioritising treatment goals among older patients with cancer in a palliative setting.

PURPOSE: Traditionally, general practitioners (GPs) are not involved in cancer-related treatment decisions, despite their often long relationship with patients, and their unique position to explore patients' values, especially with older patients. Therefore, we designed a randomised controlled trial to study the effect, on self-efficacy related to treatment decisions, of a conversation about treatment goals between GPs and patients with cancer in a palliative setting.

METHODS: We aim to include 168 patients aged ≥70 years with a diagnosis of non-curable cancer, due to consult their oncologist about treatment options. In the intervention group, patients will consult their GP using an Outcome Prioritisation Tool (OPT). The control group will receive care as usual. The primary outcome will be the score on a decision self-efficacy scale after the consultation with the oncologist. Secondary outcomes will be symptoms of depression, anxiety, or fatigue. In an embedded observational study of the intervention group, we aim to assess the prioritisation of treatment goals (i.e., OPT scores), and their determinants, over a six-month period.

CONCLUSIONS: The OPTion study should provide relevant information about the effect on self-efficacy of a consultation between GPs and older patients with cancer, concerning preferred treatment goals in a palliative setting. Dutch Trial Register NTR5419.