Quantification techniques for circulating tumor cells

• Properties of eight types of circulating tumor cell (CTC) detection techniques.
• We review CTC detection techniques in cancer diagnosis.
• We compare different CTC detection techniques.
• We discuss challenges and perspectives of the CTC detection techniques.

Circulating tumor cells (CTCs) are tumor cells dislodged from tumors into the bloodstream. In the past two decades, numerous studies have suggested that CTCs play a major role in cancer metastasis. As such, CTCs are currently considered potentially important cancer biomarkers that may significantly improve cancer diagnosis and prognosis, aid drug development and offer personalized treatments for cancer patients. So accurate enumeration or detection of CTCs is a highly sought after technology to improve cancer management. However, the rarity of CTCs poses significant challenges to the sensitivity and the reliability of their detection. We thoroughly review state-of-the-art detection technologies for CTCs to help researchers in the development of more efficient CTC detection technologies. In this review, we summarize recent advances in the detection of CTCs. We also assess emerging techniques for CTC detection, such as telomerase-based and aptamer-based assays.