A large analysis of 1,763 patients with advanced solid tumors found that the presence of circulating tumor DNA (ctDNA) in blood or cerebrospinal fluid (CSF) is linked to a higher risk of brain metastases and poorer survival. The study, a systematic review and meta-analysis, combined data from multiple studies to assess the diagnostic and prognostic value of ctDNA.
Patients with ctDNA in their blood had a 67% higher chance of having brain metastases compared to those without detectable ctDNA. Those with ctDNA in their spinal fluid had nearly three times the risk of dying during follow-up. The predictive power of next-generation sequencing (NGS) for brain metastases was also notably higher when ctDNA was present.
Importantly, the study did not report any safety concerns because it analyzed existing data rather than testing a new treatment. The findings suggest that ctDNA testing, which is non-invasive, could help doctors identify patients at higher risk for brain metastases and tailor monitoring or treatment accordingly.
However, this is a meta-analysis of observational studies, so it cannot prove cause and effect. The results should be interpreted cautiously, and more research is needed before these tests become routine. For now, the findings highlight the potential of ctDNA as a tool for risk assessment in advanced cancer.