International Federation of Gynecology and Obstetrics Endometrial 2023 Is Better For Radiation Oncology Patients

The International Federation of Gynecology and Obstetrics (FIGO) 2023 staging system for endometrial cancer has marked changes from the previous staging system instituted 14 years prior in 2009. The new staging system includes nonanatomic factors for the first time (lymphovascular space invasion and histology) and molecular classification, which impacts the stage in early-stage disease (IAm_POLEmut and IICm_p53abn). The purpose of these changes was to provide (1) high accuracy in the predictive prognosis for patients and (2) identification of distinct treatment-relevant subgroups. Our understanding of the biology and natural history of endometrial cancer has undergone a radical transformation since the Cancer Genome Atlas results in 2013. The 2023 FIGO staging system harmonizes and integrates old and new knowledge on anatomic, histopathologic, and molecular features. Moreover, FIGO 2023 has distinct substages that improve adjuvant treatment decision making. Although the practicality of the new staging system has been debated, we postulate that FIGO 2023 is more useful for radiation oncologists aiming to provide personalized care recommendations. FIGO 2023 requires a change in our perception of a staging system, from a traditional anatomic borders-based system to a staging system integrating anatomy and tumor biology as pivotal prognostic factors for patients while providing important information for treatment decision making.