FIGO staging of endometrial cancer: 2023

Abstract

Introduction Many advances in the understanding of the pathologic and molecular features of endometrial cancer have occurred since the FIGO staging was last updated in 2009. Substantially more outcome and biological behavior data are now available regarding the several histological types. Molecular and genetic findings have accelerated since the publication of The Cancer Genome Atlas (TCGA) data and provide improved clarity on the diverse biological nature of this collection of endometrial cancers and their differing prognostic outcomes. The goals of the new staging system are to better define these prognostic groups and create substages that indicate more appropriate surgical, radiation, and systemic therapies. Methods The FIGO Women's Cancer Committee appointed a Subcommittee on Endometrial Cancer Staging in October 2021, represented by the authors. Since then, the committee members have met frequently and reviewed new and established evidence on the treatment, prognosis, and survival of endometrial cancer. Based on these data, opportunities for improvements in the categorization and stratification of these factors were identified in each of the four stages. Data and analyses from the molecular and histological classifications performed and published in the recently developed ESGO/ESTRO/ESP guidelines were used as a template for adding the new subclassifications to the proposed molecular and histological staging system. Results Based on the existing evidence, the substages were defined as follows: Stage I (IA1): non-aggressive histological type of endometrial carcinoma limited to a polyp or confined to the endometrium; (IA2) non-aggressive histological types of endometrium involving less than 50% of the myometrium with no or focal lymphovascular space invasion (LVSI) as defined by WHO criteria; (IA3) low-grade endometrioid carcinomas limited to the uterus with simultaneous low-grade endometrioid ovarian involvement; (IB) non-aggressive histological types involving 50% or more of the myometrium with no LVSI or focal LVSI; (IC) aggressive histological types, i.e. serous, high-grade endometrioid, clear cell, carcinosarcomas, undifferentiated, mixed, and other unusual types without any myometrial invasion. Stage II (IIA): non-aggressive histological types that infiltrate the cervical stroma; (IIB) non-aggressive histological types that have substantial LVSI; or (IIC) aggressive histological types with any myometrial invasion. Stage III (IIIA): differentiating between adnexal versus uterine serosa infiltration; (IIIB) infiltration of vagina/parametria and pelvic peritoneal metastasis; and (IIIC) refinements for lymph node metastasis to pelvic and para-aortic lymph nodes, including micrometastasis and macrometastasis. Stage IV (IVA): locally advanced disease infiltrating the bla...

Letter to the editor: FIGO Staging of endometrial cancer: 2023

“…The authors decided to describe tumors in Stages IA and IB as "non-aggressive" (low-grade endometrial carcinoma grades I and II). 1 Furthermore, Stages III and IV are applicable to all types and grades of endometrial cancer; aggressive and non-aggressive! Metastasized low-grade endometrial carcinoma is well reported.…”

“…This is emphasized further in the definition of Stage IC, "Aggressive histological types limited to a polyp or confined to the endometrium". 1 However, the authors included gastric-type adenocarcinoma and mesonephric-like adenocarcinoma in the definition of aggressive tumors. To my knowledge, to date, recognizable non-invasive component is not reported in these tumor types.…”

“…Hence, they qualify for a higher stage category. The authors decided to describe tumors in Stages IA and IB as “non‐aggressive” (low‐grade endometrial carcinoma grades I and II) 1 . Furthermore, Stages III and IV are applicable to all types and grades of endometrial cancer; aggressive and non‐aggressive!…”

The 2023 FIGO Staging System for Endometrial Carcinoma

“…The recently published 2023 International Federation of Gynecology and Obstetrics staging system for endometrial carcinoma (FIGO 2023) 1 incorporated several substantive changes to the previous version (FIGO 2009) 2 . These changes are a reflection of the numerous advances that have been made in the intervening period regarding prognostication and risk stratification, recognition of the myriad variables that place a given patient in a particular risk group, and improvements in the pathologic determination of such variables 3–6 .…”

“…These changes are a reflection of the numerous advances that have been made in the intervening period regarding prognostication and risk stratification, recognition of the myriad variables that place a given patient in a particular risk group, and improvements in the pathologic determination of such variables 3–6 . The comparatively more nuanced risk stratification in FIGO 2023 is evidenced by the fact that it is comprised of 4 primary, 12 secondary, 9 tertiary, and 4 quaternary stages, whereas FIGO 2009 was comprised of 4 primary, 7 secondary, 2 tertiary, and 0 quaternary stages 1,2 (Table 1). In addition, FIGO 2023 redefines several stages in FIGO 2009, assigns a tertiary-level stage for cases that meet criteria for simultaneous “low-grade endometrioid carcinomas limited to the uterus and ovary” (IA3), and incorporates anew such variables as histotype/tumor grade, lymphovascular invasion, and extent of nodal involvement into staging determinations 1 .…”