French recommendations for clinical practice Nice-Saint-Paul de Vence 2022-2023: histomolecular diagnosis of endometrial carcinomas

The characterisation of endometrial carcinomas has been recently modified and enriched by molecular classification, the integration of which now impacts therapeutic decisions on whether adjuvant therapy should be administered or not in localized tumors, and influences treatment selection in advanced disease. Mandatory information includes histological type according to WHO 2020 classification, histological grade, hormone receptors status and molecular classification, the main new elements to provide being analysis of MMR proteins, p53 status and POLE status in selected cases. Sampling and preparation of material must be performed adequately to allow complete analysis. Numerous markers can be used to better define histological type, distinguish between primary lesion or metastases, or provide prognostic information. Determination of MMR/MSI profile is complex but well defined by guidelines that precisely describe techniques to be used and interpretation rules. Knowledge of POLE status is useful to guide therapeutic strategy, especially to consider de-escalation in stages I and II, in particular in case of high grade and/or p53 mutated tumors. This is why indications of POLE determination must be well defined. Finally, oncogenetics consultation is recommended in dMMR tumors (except in case or MLH1 promoter methylation) and in patients with evocative familial history.