Introduction To further subclassify copy number-low endometrial carcinomas (CNL-EC) based on immunohistochemistry (IHC) with prognostic implications.
Methods We compiled EC patients who received their primary treatment at our institution from 2014 to 2022, and who had CNL-EC based on a surrogate of The Cancer Genome Atlas (TCGA) prognostic EC molecular subtype. Estrogen receptor (ER) and PTEN IHC was performed.
Results A total of 104 patients with CNL-EC were included. Eighty eight of 104 (84.6%) were ER positive by IHC, with 86 of 88 (97.7%) with endometrioid morphology. ER-positivity was found in conjunction with PTEN mutation, identified by genomic profiling, in 81.8[EL1]%. After combining histology and grade into a single variable (low-grade vs high-grade endometrioid or non-endometrioid (NE)) multivariate analysis demonstrated that only ER IHC status and the combined histology/grade variable are significant contributors to overall survival (HR=8.6 and 9.8, respectively, P=0.02 and P=0.002, respectively). Of the 14 deaths documented in this cohort, all but three had either high-grade and/or NE, or ER-negative tumors.
Conclusion/Implications These data highlight the importance of ER-IHC testing in CNL-EC and supports subclassify CNL tumors into 2 prognostic groups: a higher-risk group including FIGO grade 3, ER-negative endometrioid tumors and/or non-endometrioid features, and a more favorable group (FIGO grade 1/2 endometrioid ER positive carcinomas). Utilizing ER-IHC with histology and FIGO grade allows for better risk-stratification of patients with CNL-EC.
Statistics from Altmetric.com
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.