Abstract 5640
Background
The aim of this study was to assess the prognostic and predictive value of an untargeted assessment of tumor fractions in the plasma of metastatic breast cancer patients and to compare circulating tumor DNA (ctDNA) with circulating tumor cells (CTC) and conventional tumor markers.
Methods
Patients and methods: 29 patients with metastatic breast cancer were included in this single-institution observational cohort study. Blood samples were obtained at first diagnosis of metastases, during several lines of treatment, and/or at every further moment of progression/development of new metastases. We assessed tumor fractions in plasma using an untargeted mFAST-SeqS method. CTCs were captured using a sized-based microfilter and identified as nucleated, cytokeratin positive/CD45 negative cells. Resulting ctDNA z-scores were compared to tumor fractions established with the recently published ichorCNA algorithm and associated with the clinical outcome.
Results
We observed a close correlation between mFAST-SeqS z-scores and ichorCNA ctDNA quantifications. Patients with mFAST-SeqS z-scores above three (34.5%) showed significantly worse overall (p = 0.014) and progression-free survival (p = 0.018) compared to patients with lower values. Elevated z-score values were clearly associated with radiological proven progression. In contrast, baseline CTC count, CEA, and CA15-5 had no prognostic impact on the outcome of patients in the analyzed cohort.
Conclusions
This proof of principle study demonstrates the prognostic impact of ctDNA levels detected with mFAST-SeqS as a very fast and cost-effective means to assess the ctDNA fraction without prior knowledge of the genetic landscape of the tumor. Furthermore, mFAST-SeqS-based ctDNA levels provided an early means of measuring treatment response.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Krebshilfe Steiermark.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
4906 - Tumor-infiltrating lymphocytes (TILs) in patients with epithelial ovarian cancer undergoing neoadjuvant chemotherapy: A restrospective study
Presenter: Sara Giovannoni
Session: Poster Display session 2
Resources:
Abstract
3919 - Prognostic significance of elements of the adaptive immunity in the microenvironment of epithelial ovarian cancer.
Presenter: Periklis Foukas
Session: Poster Display session 2
Resources:
Abstract
5139 - Neutrophil-to-lymphocyte ratio predicts platinum sensitivity in epithelial ovarian cancer patients: a MITO24 retrospective study
Presenter: Alberto Farolfi
Session: Poster Display session 2
Resources:
Abstract
4212 - The prognostic impact of monocyte to lymphocyte ratio (MLR) in advanced epithelial ovarian cancer (EOC)
Presenter: Marc Cucurull Salamero
Session: Poster Display session 2
Resources:
Abstract
5123 - TP53 Hotspot mutations as immunoreactive neoantigens define a signature with differential survival outcomes in advanced ovarian cancer
Presenter: Marica Garziera
Session: Poster Display session 2
Resources:
Abstract
3795 - Use of bevacizumab (Bev) in real life for first-line (fl) treatment of ovarian cancer (OC)/ The GINECO ENCOURAGE cohort of 500 French patients
Presenter: Dominique Berton-Rigaud
Session: Poster Display session 2
Resources:
Abstract
2359 - Phase II study: Letrozole maintenance therapy after first line chemotherapy in patients with advanced serous and endometrioid ovarian cancer
Presenter: Alexandra Tyulyandina
Session: Poster Display session 2
Resources:
Abstract
3619 - Baseline IPI (Immune Prognostic Index) predicts survival in patients with advanced cervical cancer treated with immune checkpoint inhibitors (ICI).
Presenter: Felix Blanc-Durand
Session: Poster Display session 2
Resources:
Abstract
3474 - Preselecting tumor-infiltrating lymphocyte subsets to implement adoptive inmmunotherapy in ovarian cancer
Presenter: Diego Salas-Benito
Session: Poster Display session 2
Resources:
Abstract
5134 - Early prediction of the platinum-resistant relapse risk using the CA125 modeled kinetic parameter KELIM: a pooled analysis of AGO-OVAR 7 & 9; ICON 7 (AGO/GINECO/ MRC CTU/GCIG trials).
Presenter: OLIVIER COLOMBAN
Session: Poster Display session 2
Resources:
Abstract