Saman Milanizadeh - Gastroenterology and Liver Diseases Research Center, Shahid Beheshti University of Medical Sciences, Tehran,Iran#Nastaran Center for Cancer Prevention (NCCP), Mashhad, Iran
Mahsa Khanyaghma - Gastroenterology and Liver Diseases Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Pedram Azimzadeh - Gastroenterology and Liver Diseases Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Ashkan Baradaran - Medical Genetics Research Center, Mashhad University of Medical Sciences, Mashhad, Iran

New evidences have been raised suggesting that, cancers, as well as normal tissues, mightalso be hierarchically organized. Thus a minor fraction of tumor cells, endowed with stem celllikefeatures, and so termed cancer stem cells (CSCs), have been known as responsible fortumor initiation and maintenance. Another cell group which has caused controversies andcirculates freely in the peripheral blood of cancer encountered patients is circulating tumorcells (CTCs). They defined as tumor cells that either primary sites or metastases are culprit ofthem. Characteristics and detection methods of CTCs and CSCs and their therapeuticapplication have been explored in this review with focus on their similarities and differences.

Cancer Stem Cell (CSCs), Circulating Tumor Cells (CTCs), Epithelial-Mesenchymal Transition (EMT), CSC Detection, CD Markers