Timo Soeterik

20 CHAPTER 1 enabled the initiation of several scientific projects and quality improvement initiatives, including “Care for Outcome”. 52 Collaborations of the Santeon hospitals are growing and are extending beyond the Dutch border. For instance, Santeon contributes to the True NTH Prostate Cancer global registry, an initiative funded by the Movember foundation. 53 The present thesis, describing the outcomes of Santeon prostate cancer research, further builds on the prior work of the Santeon VBHC prostate cancer project. THESIS OBJECTIVES AND STRUCTURE Thesis objectives The objectives of this thesis are to evaluate the outcomes of a large real-world cohort of prostate cancer patients with regard to: (1) the outcomes of active surveillance, focusing on patient selection criteria and follow-up intensity, (2) the impact of MRI on staging as well as consequences of staging such as extent of surgery, (3) implementation of MRI information into available and novel prediction models. This thesis is structured into five parts, including 10 chapters. Chapter 1 includes a general introduction and summary of the current state of knowledge. Part I Optimising Active Surveillance In Part I of this thesis, we report the outcomes of AS in a real-world multi-centre cohort. In Chapter 2 , we will describe patient selection patterns for AS in daily practice. We test the hypothesis that selection for AS in real-world practice may be less stringent compared with AS performed in a strict trial setting, by determining the percentage of patients not meeting one or more AS eligibility criteria used in the largest ongoing AS study (PRIAS). In addition, we will assess the outcomes of patients meeting all criteria (PRIAS-eligible), and those not meeting one or more criteria (PRIAS-ineligible); assuming that PRIAS-ineligible patients have an increased risk of disease progression as well as development of metastasized disease. The second chapter of Part I (Chapter 3) regards an analysis of the same cohort, focusing on the compliance with the follow-up protocol of the PRIAS study. Besides less stringent patient selection for AS, we assumed that follow-up intensity may also be less strict in daily clinical practice, compared to the trial setting. We will determine the compliance with the PRIAS follow-up protocol, with regard to repeat biopsy testing and PSA monitoring. In addition, we will test the hypothesis that non-compliant monitoring increases the risk of unfavourable outcomes, by comparing rates of metastasis of patients with PRIAS non-compliant and PRIAS compliant monitoring.