Circulating tumor cells (CTCs) are a prognostic marker in metastatic breast cancer, but their predictive value to monitor treatment efficacy still needs further investigation. The aim of this study was to test whether persistent elevation of circulating tumor cells (CTCs) at both baseline and before 2nd cycle of a new treatment can serve as an early predictive marker of disease progression in patients with metastatic breast cancer using the predefined 5 CTC/7.5 ml threshold.
Eighty-five patients with stage IV breast cancer who met the eligibility criteria were enrolled in the study. Before starting a new treatment, all patients underwent full imaging studies and blood sampling for CTC enumeration. Patients with
At baseline, 44 (51.8%) of the 85 eligible patients did not have increased CTC levels. Of the other 41 patients with ≥ 5 CTCs /7.5 ml blood, only 38 patients had CTCs evaluation at first follow-up before 2nd cycle (CTCFU) that showed 25 (65.8 %) patients had
This study supports the significance of elevated CTCs before C2 in MBC patients starting a new line of chemotherapy as an early predictive marker of disease progression, thus, monitoring treatment benefit. It confirmed the independent prognostic significance of CTCs.
Clinical trial identification
not applicable, no trial protocol number
Legal entity responsible for the study
The Ethics Committee of the Faculty of Medicine, Assiut University
Assiut University Hospitals
All authors have declared no conflicts of interest.