liquid biopsy

Liquid Biopsy is a modern and non-invasive surgical technique. It makes it easier to study tumor cells using a simple blood test. Identifying traces of cancer in the blood make it easier to recommend a treatment plan that will work for that patient. Liquid biopsy test technology is a great way of detecting epidermal growth factor receptor (EGFR) gene mutation, which normally occurs in up to 35% of patients with non-small cell lung cancer. Unlike most early research of liquid biopsies that focused mainly on breast, lung and prostate cancer, this technology is likely to impact all type of cancers.

Liquid Biopsy:

liquid biopsy

Advantages-

  • Liquid Biopsy requires only 5 milliliters of blood and the procedure is much quicker than the surgical biopsy. This makes it much more tolerable procedure to perform as compared to surgical biopsy.
  • The convenience and tolerability have been the major boost for patients. However, the main benefits lie on the ability of the technology to detect the progression of cancer or treatment resistance of the disease among the patients before triggering clinical symptoms or appearing on an imaging scan.

Note that most cancer has more than one genetic mutations and are not necessarily the same in all parts. Past researchers have shown that tissue samples removed for biopsy
may not be able to show all mutations of cancer. However, liquid biopsy has shown better chances of detecting most cancer cell mutations. Products like cfPure™ Cell Free DNA Extraction Kit (100 ml) from Biochain are used to perform liquid biopsies.

Challenges:

More theoretical understanding bout ctDNA, exosomes, and CTCs is still necessary to uncover if the molecular profile generated from this technology truly reflects the state
of the disease. To confirm that, it is important to understand the origin and dynamics of these tumor parts in the circulation. Furthermore, it is important to determine their biological significance and clinical relevance.

Although there are various hypotheses that explain the existence of tumor in DNA in the bloodstream, there are no specific ways of determining release and dynamics of cfDNA. Research has shown that some cases of cancer with detectable ctDNA may not have a detectable level of CTCs. This shows that exceptions still exist, which make it clear that the underlying biology behind the relationship between CTC and ctDNA requires further research.

The other challenge in the implementation of liquid biopsy. Whether or not ctDNA truly offers a full representation of a patient with cancer. A study on the extent of which ctDNA represents metastatic heterogeneity revealed that genomic architecture of the disease can infer from tumor biopsies and plasma samples. Indeed, mutation level in the plasma shows that ctDNA makes it possible to perform real-time sampling.

It has also been demonstrated that the total ration of ctDNA within the entire cfDNA varies greatly from one patient to another. However, research has also shown that
despite the high variability, intra-patients levels correlated with the progression of the disease. This allows the use of ctDNA levels as a proxy measurement for tumor progression.

Final Verdict:

Liquid biopsy offers a great way of studying tumor cells using a simple blood test. Although this method is still new and has its own challenges, preliminary uses have
shown that this method can serve as a viable diagnosis especially during pre-analytical steps.