Abstract CT067: The Prospective Dutch ColoRectal Cancer Cohort (PLCRC): a prospective nationwide observational cohort study providing the infrastructure for registry based trials
Authors: Vink Geraldine , Braak Robert Coebergh van den , Bloemendal Haiko , Coupé Veerle , Elferink Marloes , Erdkamp Frans , Grevenstein Helma van , Groot Jan-Willem de , Ijzermans Jan , Intven Martijn , Los Maartje , Noo Mirre de , Oijen Martijn van , Punt Cornelis , Rietbroek Ron , Roeloffzen Wilfried , Schiphorst Anandi , Schipper Huig , Stockmann Hein , Tjin-a-Ton Manuel , Velden Ankie van der , Verhaar Marlies , Vles Wouter , Zimmerman David , Meijer Gerrit , Koopman Miriam 
Published: July 2017

Abstract
Background: Colorectal cancer (CRC) was once considered a single entity, but now appears to exist of multiple, often molecular defined, subclasses. These subclasses have implications for treatment, and hamper the feasibility of prospective randomized clinical trials which require large sample sizes. To anticipate further developments and to obtain more detailed insight in the outcome of daily practice, the Prospective Dutch CRC cohort (PLCRC) was initiated. In this prospective observational multicenter cohort, patients with all stages of colorectal cancer are included, and clinical data, tissue, blood samples and patient-reported outcome measures are collected. The cohort serves as an infrastructure for registry based trials in the Netherlands (CRC incidence approximately 16.000 patients per year).
Methods: Patients ≥18 years with histologically proven stage I-IV CRC are eligible to participate. The informed consent includes consent for systematic collection of long-term clinical data and optionally 1) standardized collection of tissue and blood samples; 2) being informed when clinically relevant DNA mutations are detected; 3) patient-reported outcome questionnaires; and 4) invitation for future interventional studies according to (amongst others) the cohort multiple randomized controlled trial design (cmRCT).
Results: In 2016 the number of participating hospitals increased from 6 to 17. The number of included patients roughly doubled to more than 1100 patients. The PLCRC infrastructure is used in the execution of fifteen studies, which amongst others focus on the prognostic value of circulating tumor DNA, the quality of life during treatment with new compounds and the influence of nutrition on treatment outcome. The studies use the option to repeatedly withdraw blood, send out PROMs and/or randomize patients according to the cmRCT design. The study populations in the substudies vary from newly diagnosed stage 2 colon cancer to non-liver limited metastatic CRC. In 2017, at least 20 hospitals which are currently in the initiation process will be added with which a 50% coverage of the Dutch hospitals will be reached.
Conclusions: PLCRC provides long-term clinical data, tissue, blood samples and patient-reported outcome measures of a large cohort of patients with colorectal cancer. The cohort will be representative of the colorectal cancer population in the Netherlands. Multiple studies are ongoing making use of the infrastructure provided. These studies will make it possible to optimize treatment for specific small subgroups.
Citation Format: Geraldine Vink, Robert Coebergh van den Braak, Haiko Bloemendal, Veerle Coupé, Marloes Elferink, Frans Erdkamp, Helma van Grevenstein, Jan-Willem de Groot, Jan Ijzermans, Martijn Intven, Maartje Los, Mirre de Noo, Martijn van Oijen, Cornelis Punt, Ron Rietbroek, Wilfried Roeloffzen, Anandi Schiphorst, Huig Schipper, Hein Stockmann, Manuel Tjin-a-Ton, Ankie van der Velden, Marlies Verhaar, Wouter Vles, David Zimmerman, Gerrit Meijer, Miriam Koopman. The Prospective Dutch ColoRectal Cancer Cohort (PLCRC): a prospective nationwide observational cohort study providing the infrastructure for registry based trials [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr CT067. doi:10.1158/1538-7445.AM2017-CT067