The authors observed 149 patients with nodal goiter and 39 patients with thyroid cancer for thyroid cancer risk factors. Frequency of thyroid cancer, malignancies and thyroid gland diseases was studied in the families of the observed patients. BRAF T1796A gene mutation was identified in 50 tissue samples of thyroid cancer of the patients. It has been shown, presence in relatives thyroid cancer and malignant new growths is thyroid cancer risk factor. BRAF T1796A mutation was identified in 27% of papillary thyroid cancer samples and its identification may be used to determine this risk factor of the development of papillary thyroid cancer clinical form.