Liquid biopsy a newly emerged non-invasive tool to detect several types of cancer is based on detecting circulating _________.

The correct answer is option 3

Key PointsLiquid biopsy is a relatively new and non-invasive approach for detecting various types of cancer. It involves analyzing components found in bodily fluids, such as blood, to provide insights into the presence of cancer or its genetic characteristics. The correct answer is: Tumor DNA

• Tumor proteins:
  • ​Tumor proteins can indeed be detected using liquid biopsy methods, but they are not the primary target.
  • Circulating tumor proteins, such as tumor markers, can provide valuable information, but they are often used in conjunction with other components like tumor DNA.
• Tumor cells:
  • Circulating tumor cells (CTCs) are cancer cells that have detached from a primary tumor and entered the bloodstream.
  • Detecting CTCs in a liquid biopsy can provide information about the spread of cancer and its potential to metastasize.
  • However, the primary focus of liquid biopsy for most applications is not detecting whole tumor cells but rather components shed by tumors, such as DNA.
• Tumor DNA:
  • ​This is the correct answer.
  • Liquid biopsy often involves the detection of circulating tumor DNA (ctDNA) in the bloodstream.
  • When cancer cells die or undergo apoptosis, they release small fragments of DNA into the blood.
  • These ctDNA fragments can carry genetic mutations specific to the tumor. By analyzing these mutations, researchers and clinicians can gain insights into the presence of cancer, its genetic characteristics, and even monitor its response to treatment.
• Bone marrow cells:
  • Bone marrow cells are not a common target for liquid biopsy.
  • Liquid biopsy typically focuses on components that can be found in easily accessible bodily fluids, such as blood.
  • While bone marrow examination (usually through a bone marrow biopsy) can provide valuable diagnostic information for certain types of cancers, it is not a primary component of liquid biopsy.