Liquid Biopsy in Cancer Treatment

Liquid Biopsy in Cancer Treatment

• Liquid biopsy is a minimally invasive, potentially transformative tool in oncologic care with multiple clinical applications.
• It involves the collection and study of circulating analytes such as tumor-derived cells or cellular products like DNA and RNA.

Circulating Tumor Cells (CTCs)

• CTCs arise from primary and metastatic tumor sites and are responsible for the development of distant metastases.
• Analysis of CTCs allows for genomic and proteomic profiling.
• Blood plasma concentrations of CTCs have been correlated with prognosis and treatment response across many tumor types.

Circulating Tumor DNA (ctDNA)

• ctDNA are tumor-specific, cell-free DNA fragments released from dying tumor cells, distinguishable from germline DNA due to somatic genomic alterations, genetic mutations, or methylation patterns.
• ctDNA levels correlate with prognostication and treatment response.
• ctDNA has demonstrated clinical utility and is used to select targeted therapies.

Advantages of Liquid Biopsy

• Minimally invasive nature, avoiding discomfort, complications, and costs associated with biopsy procedures.
• Provides an alternative tumor procurement option when tissue biopsies are limited by inaccessible locations, poor cellular viability, and challenges with long-term storage.
• Offers unique advantages for novel clinical applications.

Clinical Applications of Liquid Biopsy

• Detection of minimal residual disease (MRD) to determine patients at risk for recurrence and guide treatment escalation and de-escalation.
• Postoperative ctDNA levels are a strong predictor of disease recurrence, often preceding serum carcinoembryonic antigen elevation and radiographic changes.
• Potential use for adjuvant therapy escalation and de-escalation.

This quiz covers the role of liquid biopsy in cancer treatment, including circulating tumor cells and their analysis for genomic and proteomic profiling.