of data on the improvement of outcomes after implementation of GA in decisionmaking. 25 Since patients have different priorities regarding what is considered an optimal outcome of treatment, it is still unknown which outcome measure captures 'optimal treatment' best.
PATIENT GOALS AND PREFERENCESDue to the risk of complications and functional decline following surgery, radiation therapy, systemic or multimodality treatment, decision-making in older patients with cancer comprises trade-offs. 26,27 To guide patients in the process of shared decisionmaking, it is important to assess their priorities regarding treatment outcomes in order to align the treatment to these priorities. [28][29][30] However, it has been shown that healthcare professionals often have limited knowledge of the goals, preferences, and values of their patients. [31][32][33] A decision aid that can support a goal-setting conversation is the Outcome Prioritization Tool (OPT, figure 1). The OPT uses four universal health outcomes and is thereby neither disease nor treatment specific. This makes the tool usable in different settings, and for patients with multiple coexisting conditions. 34 The four health outcomes used in the OPT are: extending life, maintaining independence, reducing pain and reducing other symptoms (such as dyspnoea or nausea). Health outcome prioritization has been shown to be feasible for older patients. 35 The OPT uses a trade-off principle for competing outcomes, i.e. the notion that reaching a certain outcome can have a negative impact on another outcome. 36 Using the OPT, the patient is invited to prioritize between the four health outcomes and rate these in order of importance. 37 The OPT has mostly been studied in older patients with multimorbidity. 37,38 Little is known about the use of the OPT in clinical decision-making regarding intensive treatments (such as cancer therapy or surgery).
MULTIDISCIPLINARY DECISION-MAKING IN CANCER CAREThe Netherlands, and many other countries, have national guidelines requiring multidisciplinary discussion of cancer patients. Between 80-99% of oncological patients are discussed in a multidisciplinary team (MDT) meeting. [39][40][41] Oncological MDTs, or tumor boards, are usually organized by tumor type and consist of a group of professionals from different disciplines, including surgeons, medical oncologists, radiation oncologists, pathologists, radiologists, and nurses. 42 Most MDTs meet weekly. The aim of these MDTs is to standardize and optimize cancer care according to current guidelines and facilitate complex decision-making. These MDTs play an important role in the decision-making for patients with cancer. It has, however, been shown that the process to come to the optimal treatment advice in oncological MDTs can be suboptimal for older patients, by lacking patient-centered information, such as information about the patient's context, level of frailty, and the goals and preferences. [43][44][45][46]