Patients need to be well informed about those outcomes that matter most to them to be able to make good decisions between different oncologic treatment options. Research shows that patient-centred data on quality of life and physical, social and cognitive functions are important to patients besides the more commonly used disease-centred outcomes. Current design and reporting of outcomes in oncologic studies does not provide enough information on these necessary patient-centred outcomes. Optimizing oncologic care and research requires a patient-centred focus instead of a disease-centred focus.