Unlocking the crystal ball: Personalized communication of treatment outcome predictions to support decision making by esophageal and gastric cancer patients

When a patient gets diagnosed with esophageal or gastric cancer a complex decision must be made: which treatment to start? To be able to participate in shared decision making, patients need to be well-informed on treatment options and their possible outcomes, such as chances of survival, risks of side effects and expected quality of life. However, clinicians do not have a crystal ball, so communication about treatment outcomes can be complicated. This dissertation’s aims were twofold: 1. To paint a picture of information giving and decision making in esophagogastric cancer and 2. To improve the information given to patients about treatment outcomes in order to support their decision making. We described decision making in the setting of curative treatment of esophageal cancer. Subsequently, we explored shared decision making and its potential relation to less beneficial outcomes. Zooming in on information giving, we described clinicians’ information giving about tobacco and alcohol use during treatment and we summarized the literature on the effects of different formats of information giving about treatment risks and benefits. To aid clinicians in providing this complicated information about treatment and treatment outcomes, we developed a prediction tool and supporting communication skills training. After pilot testing, we evaluated the effect of the tool and training in a multicenter clinical trial. The intervention resulted in clinicians providing information significantly more precise, more personalized to patients' clinical characteristics, more tailored to patients' needs and preferences and more often supported by visualizations. Although ‘crystal ball’ might be overstated, our intervention does seem helpful in improving communication about treatment.