Fig. 1 Flowchart of participants. The red box concerns the participants in the current study which is part of a larger study in which 266 patients with metastatic lung cancer participated. In that study, patients could participate multiple times in the study resulting in 247 individual patients from whom the relatives could be approached. Only relatives of deceased patients were eligible to participate. In the end, 118 relatives participated in this interview study. * consent from patient and relative was asked at the start of the treatment. ** Patients were allowed to participate twice in the questionnaire study when they sequentially received another treatment