a new meta-analysis and systematic review found.
“Circulating tumor DNA (ctDNA) has been extensively studied as a prognostic biomarker in early breast cancer. However, there is a significant heterogeneity in the study results, which is probably related to the fact that each individual study included different patient populations, collected blood at different time points, and used different methods (assays) for ctDNA analysis,” said Guilherme Nader Marta, MD, of the Institut Jules Bordet, Anderlecht, Belgium, in an interview.
“The aim of our study was to summarize the available evidence that has been presented so far on this topic by performing a systematic review and meta-analysis including studies that reported the association between ctDNA detection and long-term outcomes,” said Dr. Nader Marta, who coauthored the new research, which was presented as a poster (Poster 26P) at the European Society for Medical Oncology (ESMO) Breast Cancer annual congress.
Methods and results
The authors identified 57 studies including data from 5,729 individuals with early breast cancer. The 44.5% for whom stages were reported consisted of 18.3% with stage I disease, 60.0% with stage II, and 21.5% with stage III. Patients’ ctDNA collection was divided into three groups: baseline, after neoadjuvant therapy (End-of-NAT), and during follow-up care; ctDNA assays were classified as tumor-informed or non–tumor-informed.
The detection of ctDNA at any time point during diagnosis and treatment was associated with worse disease-free survival (DFS) and overall survival (OS), compared with no ctDNA. The association was stronger in tumor-informed assays, the researchers said.
For disease-free survival, the overall multivariate hazard ratios were 2.5, 5.5, and 7.2 for ctDNA detection at baseline, End-of-NAT, and follow-up, respectively.
For overall survival, the overall multivariate hazard ratios were 3.0, 12.9, and 5.6, for ctDNA detection at baseline, End-of-NAT, and follow-up, respectively.
The pooled hazard ratios were numerically higher for both DFS and OS when ctDNA was detected at either End-of-NAT or follow-up.
In addition, detection of ctDNA was associated with a high degree of specificity (from 0.7 to 1.0) for breast cancer relapse; sensitivity ranged from 0.31 to 1.0, the researchers noted. The mean lead time from ctDNA detection to breast cancer recurrence in these cases was approximately 10 months.
Results show ctDNA detection is associated with worse survival
“Our study results demonstrate that ctDNA detection is associated with worse disease-free survival and overall survival in patients with early breast cancer, particularly when measured after treatment with tumor-informed assays,” Dr. Nader Marta said in an interview.
“As next steps, we need to build on this evidence to bring the potential benefits of this powerful prognostic tool to our patients,” said Dr. Nader Marta. “Ongoing studies exploring different management strategies based on serial ctDNA assessments will help us understand the exact role of this technology in our clinical practice.”
The study received no outside funding. Dr. Nader Marta disclosed relationships with companies including Roche and Bayer.