The recent FLAME trial has demonstrated improved local control of intermediate to high-risk prostate cancer after focal dose escalation of the visible tumor. To visualize the tumor, MRI... Show moreThe recent FLAME trial has demonstrated improved local control of intermediate to high-risk prostate cancer after focal dose escalation of the visible tumor. To visualize the tumor, MRI examinations were taken in which prostate tissue characteristics were visualized. Since this treatment strategy improves the clinical outcome of the patient, a technical analysis of the FLAME dataset is useful for the further optimization of focal dose escalation strategies.Delineation of the prostate tumor appeared to be performed differently in the participating radiotherapy departments. Considering the impact on the realized tumor dose, this analysis demonstrated the need for guidelines of tumor delineation on MRI. Due to the complex nature of the treatment plans, in addition a prediction model was developed, which identified patients for which a higher tumor dose could be planned.The application of MRI was also investigated for ‘dose painting by numbers’, in which MRI values are translated to prescription dose without interference of manual tumor delineations. Dose prescription based on MRI appeared robust to daily patient variations, a prerequisite for further development of ‘dose painting by numbers’. However, because of the absence of significant tumor changes during the treatment course, MRI was considered not suitable for early adaptive treatment. Show less
