The present invention relates to a data processing method of determining a distribution of isolines to be used for displaying a radiation dose distribution in tissue of a patient, the steps of the method being executed by a computer and comprising:d) acquiring dose distribution data comprising dose distribution information describing a radiation dose distribution in an anatomical body parte) acquiring display data comprising display information describing a predetermined display mode to be applied for displaying the dose distribution informationf) determining, based on the dose distribution data and the display data, isodose data comprising isodose information describing a distribution of is isolines to be used for displaying the dose distribution information.
