Estrogen receptor and programmed death ligand-1 expression in type 1 endometrial cancer and its associated clinicopathological characteristics

Background: This study aimed to determine the association of estrogen receptor (ER) and programmed death ligand-1 (PD-L1) expression with the clinicopathological characteristics of type 1 endometrial cancer. Materials and methods: A total of 85 patients with type 1 endometrial cancer who underwent surgery at the Dr. Soetomo Hospital, Surabaya, Indonesia were retrospectively studied. Data about the age, menopausal status, body mass index, disease stage, cell differentiation, angiolymphatic invasion, myometrial invasion, and adjuvant therapy of the patients were collected from medical records. Immunohistochemistry with ER and PD-L1 antibodies was performed on all samples. The association between ER and PD-L1 expression and clinicopathological characteristics was statistically analyzed. Results: The positivity rates of ER and PD-L1 in type 1 endometrial cancer were 68.2 % and 78.5 %, respectively. ER positivity was significantly correlated with body mass index (BMI) ≥25, premenopausal status, early stage of disease, <1/2 myometrial invasion, negative nodal metastasis, and lack of adjuvant therapy. It was also associated with age <55 years, low-grade cells, and angiolymphatic invasion, but the correlation was not significant. Meanwhile, PD-L1 positivity was significantly correlated with BMI <25, menopausal status, advanced stage of disease, high-grade cells, angiolymphatic invasion, and adjuvant therapy. It was also associated with age ≥55 years and nodal metastasis, but the correlation was not significant. Conclusion: ER and PDL-1 positivity is associated with the clinicopathological characteristics of type 1 endometrial cancer.