Protocol for the Endometriosis Research Queensland Study (ERQS): an integrated cohort study approach to improve diagnosis and stratify treatment

Introduction: Endometriosis is a common gynaecological disease associated with pelvic pain and subfertility. There are no non-invasive diagnostic tests, medical management requires suppression of oestrogens and surgical removal is associated with risk. Endometriosis is a complex genetic disease with variants in at least 27 genetic regions associated with susceptibility. Previous research has implicated a variety of biological mechanisms in multiple cell types. Endometrial and endometriotic epithelial cells acquire somatic mutations at frequency higher than expected in normal tissue. Stromal cells have altered adhesive capacity and immune cells show altered cytotoxicity. Understanding the functional consequences of these genetic variants on each cell type requires the collection of patient symptoms, clinical and genetic data and disease-relevant tissue in an integrated program.

Methods and analysis: The aims of this study are to collect tissue associated with endometriosis, chart the genetic architecture related to endometriosis in this tissue, isolate and propagate patient-specific cellular models, understand the functional consequence of these genetic variants and how they interact with environmental factors in pathogenesis and treatment response.We will collect patient information from online questionnaires prior to surgery and at 6 and 12 months postsurgery. Treating physicians will document detailed surgical data. During surgery, we will collect blood, peritoneal fluid, endometrium and endometriotic tissue. Tissue will be used to isolate and propagate in vitro models of individual cells. Genome wide genotyping and gene expression data will be generated. Somatic mutations will be identified via whole genome sequencing.

Ethics and dissemination: The study has been approved and will be monitored by the Metro North Human Research Ethics committee (HREC) and research activities at the University of Queensland (UQ) will be overseen by the UQ HREC with annual reports submitted. Research results will be published in peer-reviewed journals and presented at conferences were appropriate. This study involves human participants and was approved by RBWH Human Research Ethics Committee; HREC/2019/QRBW/56763.The University of Queensland; 2017002744. Participants gave informed consent to participate in the study before taking part.