Abstract 3879: High dimensional analysis of tumor microenvironment and heterogeneity in FIGO IB endometrial carcinomas using imaging mass cytometry

Abstract

Abstract Patients with localized endometrial carcinomas (FIGO IA and IB) have a 5-year relative survival rate of > 90%. Still, some patients with an expected good prognosis experience recurrence of disease which dramatically reduces survival rates. Currently, we lack the knowledge to predict which patients will get recurrence. We used Imaging Mass Cytometry to examine 27 proteins in tissue microarrays of 36 primary FIGO IB endometrial carcinomas, of which 17 later recurred. High dimensional images were segmented to extract single-cell information for each tumor. Distinct epithelial-, stromal- and immune cell types of the tumor microenvironment were identified and phenotyped, using protein expression intensities and unsupervised cell clustering. Neighboring cells of CD8+ cells were extracted and phenotyped. In non-recurrent tumors, more cytotoxic T cells were identified adjacent to two epithelial cell populations characterized by high vimentin and progesterone receptor expression (p < 0.01 and p = 0.02). Tumors that were enriched for vimentin showed significantly better recurrence-free survival than tumors with low vimentin or high alpha-smooth muscle actin (a-SMA) signal (p = 0.026). This study reveals distinct characteristics in the microenvironment of low stage tumors that may aid in identifying high-risk patients. Further, the study provides new insight on the pathogenic processes involved in tumor progression of endometrial cancer. Citation Format: Hilde Eide Lien, Hege Fredriksen Berg, Erling Andre Hoivik, Jone Trovik, Ingfrid Salvesen Haldorsen, Lars Andreas Akslen, Camilla Krakstad. High dimensional analysis of tumor microenvironment and heterogeneity in FIGO IB endometrial carcinomas using imaging mass cytometry [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3879.