Molecular expression characteristics confirm the malignancy concealed by morphological alterations in endometrial cancer after fertility-preserving treatment.

ABSTRACT

PURPOSE: Fertility-preserving treatment (FPT) has been widely used for young patients with early stage endometrial cancer (EC). However, the literature on the effectiveness and safety of FPT remains controversial. The aim of this study was to investigate malignant transformation in EC after FPT by immunohistochemistry (IHC). METHODS: A retrospective analysis of pre- and post-treatment biopsy specimens from 24 patients with grade 1 endometrioid adenocarcinoma (EAC) or complex atypical hyperplasia (CAH) was performed. The expression levels of ARID1A, PTEN, and ß-catenin were assessed by IHC. RESULTS: The protein expression levels of ARID1A, PTEN, and ß-catenin were not significantly different between pre- and post-treatment specimens. However, there was a significant difference between pre-treatment and normal specimens as well as between post-treatment and normal specimens. The protein expression of ß-catenin was significantly increased in patients with progression compared with those without progression after FPT. CONCLUSION: The morphologic normalization of patients with EC after FPT may not be accompanied by the absence of tumor malignancy, and ß-catenin may serve as a biomarker for the response to FPT. These results may contribute to a better understanding of the malignant transformation of EC after FPT and the optimization of treatment strategies for young patients with birth plans.