EUGENIE is a prospective multicentre interventional study, focused on improving endometrial cancer (EC) assessment by combining the new technique of genomic profiling with surgical extra uterine disease assessment. The investigators aim to correlate EC stage to each of the molecular subgroups of disease and thereby guide surgical treatment and staging of EC by determining the association between molecular classification and disease stage and evaluating if and how disease stage in each of the molecular subgroups associates with prognosis.

Current treatment for endometrial cancer (EC) includes a hysterectomy with bilateral salpingo-oophorectomy. Further surgical staging procedures (lymphadenectomy, peritoneum, and/or omentum biopsies) can be performed in order to detect metastases and determine the disease stage. The type and extent of this surgical staging depend on a pre-operative risk assessment and guides adjuvant treatment (chemo- or radiotherapy). However, this pre-operative risk assessment based on histology and imaging is relatively inaccurate: first, preoperative histology presents high intersubjective variability leading to poor reproducibility in the assignment of histotype and the concordance between preoperative histology and final histology is poor. In addition, preoperative imaging modalities are expensive, time-consuming, hampered by non-perfect accuracies, require specialized expertise, or present limitations in reproducibility and availability. As a result, this leads to an incorrect risk estimation of metastases at diagnosis in EC patients with a consequent over- or undertreatment of patients. Thus, there is an urgent need to develop risk stratification strategies that will better predict the presence and localization of metastases in EC patients and therefore more efficiently tailor surgical staging procedures.

In 2013 The Cancer Genome Atlas (TCGA) Research Network developed a new molecularly driven classification system, that divides EC tumours into the well-known four molecular subgroups (POLE, MMRd, p53abn, NSMP) and has shown to surpass histologic subtyping and grading to more efficiently predict prognosis. However, the relation between the four molecular subgroups and the risk of tumour spread beyond the uterus at diagnosis has insufficiently been investigated so far and, as a consequence, surgical staging should not yet be adapted based on the molecular endometrial cancer subtype.

Thus, new studies are needed to assess the value of surgical staging in this molecular era and EUGENIE Study has been developed to bridge this knowledge gap.

The investigators believe that the future is in integrating morphologic and molecular findings, so the preoperative diagnosis will also support accurate surgical decision making and therefore a more tailored management of all EC patients.

Inclusion Criteria:

• Voluntary written informed consent of the participant or their legally authorized representative has been obtained before any screening procedures
• Women ≥ 18 years
• First diagnosis of EC, all disease stages and all histo-types

Exclusion Criteria:

• Participant has a history of pelvic or para-aortic lymph node dissection or sampling, previous pelvic (and/or para-aortic) radiotherapy, previous neoadjuvant chemotherapy
• Any disorder, which in the Investigator's opinion might jeopardise the participant's safety or compliance with the protocol
• Any prior or concomitant treatment(s) that might jeopardise the participant's safety or that would compromise the integrity of the Study