Prognostic Relevance of Estrogen Receptor Status in Circulating Tumor Cells in Breast Cancer Patients Treated With Endocrine Therapy

Abstract

Recently, female breast cancer (BC) has surpassed lung cancer to occupy the first place of the most commonly diagnosed cancer. The unsatisfactory prognosis of endocrine therapy for breast cancer might be attributed to the discordance in estrogen receptor (ER) status between primary tumors and corresponding metastases, as well as temporal and spatial receptor status heterogeneity at point-in-time between biopsy and treatment. The purpose of this study was to evaluate the prognostic and predictive value of ER status in circulating tumor cells (CTCs) in BC patients. We analyzed ER expression on CTCs isolated using the Pep@MNPs method in 2.0 ml of blood samples from 70 patients with BC and 67 female controls. The predictive and prognostic value of ER expression in CTCs and immunohistochemistry results of biopsies for progression-free survival (PFS) and overall survival (OS) of patients in response to therapies were assessed. The detection rate for CTCs was 95.71% (67/70 patients), with a median of 8 CTCs within 2 ml of peripheral venous blood (PVB). A concordance of 76.56% in ER status between CTCs and corresponding primary tumor and 69.23% between CTCs and corresponding metastases was observed. We also found that patients with ER-positive CTCs (CTC ER+) had longer PFS and OS than those without ER-positive CTCs (CTC ER-). Our findings suggested that ER status in CTCs of BC patients may provide valuable predictive and prognostic insights into endocrine therapies, although further evaluation in larger prospective trials is required.

HER2 Expression in Circulating Tumor Cells as Prognostic and Predictive Biomarkers for Anti‐HER2 Therapy in Previously Treated Metastatic Colorectal Cancer

“…Healthy donors had few epithelial cells in 2.0 mL blood (≈0–2 CTCs, mean [0.2 CTCs], median [0 CTCs]; ≥ 1 CTCs, 14.3%), similar to other trials. [ 28,31,39 ] The number of CTCs (≈0–350 CTCs, median [2 CTCs], mean [28 CTCs]) and CTC detection rate (≥1 CTCs, 65.0%) at baseline are superior to other reports by CellSearch in 7.5 mL blood (Nanou et al., ≈0–312 CTCs, median [0 CTCs]; Iwatsuki et al., ≈0–353 CTCs, mean [18 CTCs]; Cohen et al., ≥ 3 CTCs, 26.0%). [ 29,30,35 ] Thus, sensitivity (65.0%) and specificity (85.7%) of CTC detection by TUMORFISHER are competitive in mCRC, which could be mainly attributed to the smaller size and larger number of EpCAM recognition peptides on TUMORFISHER than anti‐EpCAM antibodies on CellSearch .…”

“…Healthy donors had few epithelial cells in 2.0 mL blood (≈0-2 CTCs, mean [0.2 CTCs], median [0 CTCs]; ≥ 1 CTCs, 14.3%), similar to other trials. [28,31,39] The number of CTCs (≈0-350 CTCs, median ). [29,30,35] Thus, sensitivity (65.0%) and specificity (85.7%) of CTC detection by TUMORFISHER are competitive in mCRC, which could be mainly attributed to the smaller size and larger number of EpCAM recognition peptides on TUMORFISHER than anti-EpCAM antibodies on CellSearch.…”

“…[37] Enumeration and/or downstream analysis of CTCs isolated by TUMORFISHER could serve as valuable prognostic and/or predictive biomarkers in multiple solid tumors, including HER2 phenotyping on CTCs in advanced breast cancer. [28,38,39] Hence, it is promising to explore the clinical utility of HER2 phenotyping on CTCs by TUMORFISHER in mCRC patients who are treated with anti-HER2 therapy.…”

The Enigma of Mammaglobin: Redefining the Biomarker Paradigm in Breast Carcinoma

“…Detectable in primary lung adenocarcinomas, ER is used for predicting hormonal therapy responses in breast cancer despite its limited prognostic significance [38]. Progesterone receptor (PR)…”