Tehran University of Medical Sciences International Journal of Hematology-Oncology and Stem Cell Research 2008-2207 12 3 2018 07 04 234 247 EN Fatemeh Khatami Chronic Diseases Research Center, Endocrinology and Metabolism Population Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran Seyed Mohammad Tavangar Department of Pathology, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran 2018 03 13 2018 04 15 Thyroid cancer, one of the most widespread malignancies of the endocrine-related system that over the past three decades, has a vivid increasing rate. The diagnosis and management of it is dependent on the tumor type and stage. Thyroid cancer is divided into four main types, including PTC (papillary thyroid carcinoma), FTC (follicular thyroid carcinoma), MTC (medullarly thyroid carcinoma), and ATC (anaplastic thyroid carcinoma). The development of the noninvasive diagnostic tool for plasma genotyping, also known as “liquid biopsy”, brings a new insight for cancer diagnosis and prognosis. It is mainly containing circulating tumor DNA (ctDNA), circulating tumor cell (CTC), exosomes and extrachromosomal circular DNA (ecDNA). Liquid biopsy as a new plasma genotyping source brings a new prospective of tumor monitoring and therapy.  It beneficially reduces the need of tissue biopsy and made early recognition of relapse as well. This article summarizes its components characteristics and their benefit in diagnosis and treatment of thyroid cancer. https://ijhoscr.tums.ac.ir/index.php/ijhoscr/article/view/926 https://ijhoscr.tums.ac.ir/index.php/ijhoscr/article/download/926/646