The American Thyroid Association (ATA) has revised its guidelines for the management of medullary thyroid carcinoma (MTC). The guidelines focus on the diagnosis and treatment of both sporadic and hereditary MTC. The Task Force developed 67 evidence-based recommendations to assist clinicians in the care of patients with MTC. These recommendations are based on a systematic review of the literature and are categorized using criteria adapted from the United States Preventive Services Task Force. The guidelines emphasize the importance of genetic testing, particularly for RET mutations, in identifying hereditary MTC. The Task Force recommends changing the current risk categories for hereditary MTC to better reflect the aggressiveness of the disease. The guidelines also address the ethical considerations of genetic screening, including the duty to warn family members of potential risks. Additionally, the guidelines provide recommendations for the management of patients with MTC, including the use of calcitonin as a tumor marker and the importance of early thyroidectomy in certain cases. The guidelines also discuss the role of genetic counseling and testing in families with a history of MTC, as well as the ethical implications of prenatal and preimplantation testing. The guidelines emphasize the importance of early detection and management of MTC to improve patient outcomes.The American Thyroid Association (ATA) has revised its guidelines for the management of medullary thyroid carcinoma (MTC). The guidelines focus on the diagnosis and treatment of both sporadic and hereditary MTC. The Task Force developed 67 evidence-based recommendations to assist clinicians in the care of patients with MTC. These recommendations are based on a systematic review of the literature and are categorized using criteria adapted from the United States Preventive Services Task Force. The guidelines emphasize the importance of genetic testing, particularly for RET mutations, in identifying hereditary MTC. The Task Force recommends changing the current risk categories for hereditary MTC to better reflect the aggressiveness of the disease. The guidelines also address the ethical considerations of genetic screening, including the duty to warn family members of potential risks. Additionally, the guidelines provide recommendations for the management of patients with MTC, including the use of calcitonin as a tumor marker and the importance of early thyroidectomy in certain cases. The guidelines also discuss the role of genetic counseling and testing in families with a history of MTC, as well as the ethical implications of prenatal and preimplantation testing. The guidelines emphasize the importance of early detection and management of MTC to improve patient outcomes.