[Polineoplasia: thyroid cancer and breast cancer: incidence, causes, mechanisms of development]

The dramatic situation with the incidence and mortality from breast cancer that has developed in the last decades of the past century in the industrialized countries of the world has given this disease the status of not only a medical, but also a social problem. The society reacted to this adequately: a number of measures taken for anti-cancer propaganda, early diagnosis, development and widespread use of effective methods of treatment allowed us to reverse the unfavorable trend in mortality while recognizing the limited possibilities of modern medicine in preventing breast cancer. World trends in increasing life expectancy after curing breast cancer have led to an increase in the number of patients subsequently ill with a second malignant tumor. The attention of researchers is attracted by the combination of breast cancer and thyroid cancer.