In a systematic review and meta-analysis reported in JAMA Network Open, Cullinane et al found that higher levels of plasma circulating tumor DNA (ctDNA) were associated with poorer disease-free survival in patients with both early and advanced breast cancer, with the association being stronger with pretreatment ctDNA levels.
Study Details
The analysis included eight studies published through October 2019 including a total of 739 patients. Follow-up durations in the studies ranged from 12 months to 3 years. Analysis of the association of ctDNA with disease-free survival included analysis of early and advanced breast cancer and ctDNA measured before or after treatment, with treatment defined as surgical or oncologic treatment.
Key Findings
Elevated ctDNA before or after treatment was associated with significantly poorer disease-free survival among all patients (hazard ratio [HR] = 4.44, 95% confidence interval [CI] =2.29–8.61, P < .001), including among patients with early-stage disease (HR = 8.32, 95% CI = 3.01–22.99, P < .001) and those with locally advanced or metastatic disease (HR = 1.91, 95% CI = 1.35–2.71, P < .001).
Among all patients, elevated ctDNA in pretreatment samples was significantly associated with poorer disease-free survival (HR = 3.30, 95% CI = 1.98–5.52, P < .001), whereas the association with post-treatment samples did not achieve statistical significance (HR = 8.17, 95% CI = 1.01–65.89, P = .05).
The investigators concluded, “In this systematic review and meta-analysis, elevated plasma ctDNA was associated with a high risk of relapse. This finding suggests that plasma ctDNA may provide an excellent method to stratify risk and personalize patient follow-up.”
Carolyn Cullinane, MBBS, MCh, of the Department of General and Breast Surgery, Cork University Hospital, Ireland, is the corresponding author for the JAMA Network Open article.
Disclosure: For full disclosures of the study authors, visit jamanetwork.com.
