Understanding palliative cancer chemotherapy: about shared decisions and shared trajectories.

Most models of patient-physician communication take decision-making as a central concept. However, we found that often the treatment course of metastatic cancer patients is not easy to describe in straightforward terms used in decision-making models but is instead frequently more erratic. Our aim was to analyse these processes as trajectories. We used a longitudinal case study of 13 patients with metastatic colorectal and pancreatic cancer for whom palliative chemotherapy was a treatment option, and analysed 65 semi-structured interviews. We analysed three characteristics of the treatment course that contributed to the 'erraticness' of the course: (1) The treatment (with or without chemotherapy) contained many options; (2) these options were not stable entities to be decided upon, but changed identity over the course of treatment, and (3) contrary to the closure (option X means no option Y, Z, etc.) a decision implies, the treatment course was a continuous process in which options instead remained open. When the treatment course is characterised by these many and changeable options that do not result in closure, the shared decision-making model should take these into account. More attention needs to be paid to the erratic character of the process in which the doctor has to provide continuous information that is related to the changing situation of the patient; also, flexibility in dealing with protocols is warranted, as is vigilance about the overall direction of the process.