Medical imaging is essential for the diagnosis, treatment and follow-up of patients with cancer. Combinations of different, complementary imaging modalities are increasingly being used: multimodal imaging. This thesis describes recent developments and expected innovations in research (and application of) combined PET/CT and MRI in patients with abdominal cancer. To this end, the effect of integrated assessment of PET/CT and MRI scans was investigated. This resulted in a different result in 1 in 9 patients, as well as a positive effect on the confidence in the results. As a next step, the value of quantitative parameters from PET/CT and MRI was assessed, to predict the treatment outcome of patients with cancer of the rectum, uterine cervix or anus. This value appears to be limited, but the findings from conventional, visual image assessment, does contribute to the prediction
