Dr.Lees second lecture clinical diseases

What is a liquid biopsy?

The process of sampling and analyzing non-solid biological specimens, primarily blood.

What does ctDNA stand for?

Circulating tumor DNA, which refers to tumor-derived DNA fragments released from cells into the bloodstream.

What is the concentration range of ctDNA in blood?

Less than 0.1% to greater than 10% of total cell-free DNA (cfDNA), depending on disease type and burden.

How can ctDNA analysis impact cancer treatment?

ctDNA can be used for treatment decisions and monitoring treatment response or recurrence.

What is an actionable genomic alteration (AGA)?

Genomic changes that can be targeted for cancer treatment, primarily based on mutations, chromosomal rearrangements, and copy number variations (CNVs).

What percentage of cancer-related deaths are from cancers with no screening test available?

More than 60% of cancer-related deaths occur from cancers that do not have an available screening test.

What is the Circulating Cell-free Genome Atlas (CCGA) study?

A study that analyzes genome-wide methylation patterns for multi-cancer early detection.

What are the disadvantages of ctDNA testing compared to tissue biopsy?

ctDNA testing may have limitations such as false negatives and variable sensitivity depending on the tumor type.

What is the significance of tumor mutation burden (TMB)?

TMB is used as a biomarker for predicting the response to immunotherapy, often correlated with the neoantigen burden.

What role does ctDNA play in monitoring resistance to treatment?

ctDNA can track resistance drivers and help in the early identification of treatment failure.