The literature review presents the history on the development of modern ideas about medullary thyroid cancer, which is a little more than fifty years. It demonstrates the impressive achievements of modern science, which made it possible to move from clinical and morphological descriptions of individual cases and variants of diseases to studying and elucidating the mechanisms of their development at the molecular genetic level within a short period of time. To a large extent, this became possible thanks to the discovery of a number of combined forms of endocrine pathology, in particular multiple endocrine neoplasia syndromes among which medullary thyroid cancer plays a leading role. Based on achievements in this field, a method of surgical correction of medullary cancer even before its occurrence was proposed, which marked the emergence of a new direction in surgery— a preventive surgery. The history of studying medullary thyroid cancer begins with the discovery of a separate population of cells present in a small amount of thyroid tissue. In his report made at the meeting of the Royal College of Physicians in London on January 27, 1876, called Contribution to the minute anatomy of the thyroid of the dog, E. Cresswell Barber first described the presence of clusters of unusual cells in the gland, which morphologically differed from the known follicular cells. Currently, a new direction of clinical surgery is being formed— a preventive surgery. The basic principle of prophylactic surgery is the removal of one or another organ, if the absolute risk of developing a specific pathological process in it is proven. In the situation under consideration, this is medullary thyroid cancer, which occurs in 100% of individuals who are hereditary carriers of the mutant RET proto-oncogene. A similar risk exists for persons with some forms of colorectal cancer, malignant tumors of the mammary gland, ovaries in which their hereditary origin has been proven on the basis of detected mutations of certain genes. Intestinal resection, mastectomy, oophorectomy lead to the elimination of the potential threat of tumor development or its removal in situ, when it has not yet acquired the nature of a formed malignant neoplasm.