PhD defences M.J.M. (Milea) Timbergen

Desmoid-type fibromatosis (DTF) is a rare soft tissue tumour which mainly affects females in the reproductive ages. It can develop in the whole body but the trunk and the abdominal wall are mostly affected. DTF grows invasively and aggressively but is unable to metastasize. The majority of tumours harbor a mutation in the CTNNB1 (β-catenin) gene. This thesis encompasses of three parts. The first part  describes a literature review to summarize the knowledge and study results of targeted therapies. Differences in expression of genes related to the Wnt/β-catenin cell signaling pathway between the two most common CTNNB1 mutation types and wild-type DTF were analysed. Furthermore, differences in DNA methylation patterns between CTNNB1 mutation types were evaluated. The second part describes the development of a radiomics model to optimize the diagnostic trajectory. Furthermore, the results of international studies publishing about the success of the active surveillance approach were systematically reviewed. Lastly, the relation between risk of recurrence after surgical resection and the CTNNB1 mutation was investigated. The third part  describes health-related quality of life (HRQoL) of DTF patients. In these chapters, the most important HRQoL issues experienced by DTF patients were identified. The QUALIFIED study was developed based on these issues and aims to analyse the extent of HRQoL-problems, to compare the scores to DTF patients to those of the normative population, and to identify patients at risk for impaired HRQoL.

Due to corona, the PhD defences do not take place publicly in the usual way in the Senate Hall of the Professor Andries Querido Room. The candidates will defens their dissertation either in a small group or online.