Table 1 Comparison of ctNDA/cfDNA and CTCs [1,2,3,4]
From: Liquid biopsy: current technology and clinical applications
| Â | ctDNA/cfDNA | CTCs |
|---|---|---|
Ease of collection/isolation | Easier isolation | More difficult to isolate |
Ability to culture | Cannot be cultured | Can be cultured |
Predicting therapeutic response | Changes in levels predict response/resistance/relapse | Changes in levels can predict response/resistance/relapse |
Ability to assess genomic/transcriptomic/protein data | Can analyze DNA | Can analyze DNA, RNA, and protein |
Ability to assess functional data | No | Yes |
Ability to assess methylation | Yes | Yes |
Ability to perform fluorescent in situ hybridization analysis | No | Yes |
Ability to perform single cell analysis | No | Yes |
Ability to perform chromosomal analysis | No | Yes |
Challenges in collection/interpretation | Cell death under therapy can modify ctDNA levels Small quantities of ctDNA in circulation Can be confounded by CHIP | Heterogeneity in CTCs can affect analysis Sampling bias of captured cells (high affinity and larger size) |