RADIOIODINE-RESISTANT DIFFERENTIATED THYROID CANCER: CLINICOPATHOLOGICAL CHARACTERISTICS, MOLECULAR GENETIC ALTERATIONS. REVIEW.

Abstract

Introduction. Thyroid cancer is one of the most common endocrine malignancies. Radioactive iodine I131 is the baseline drug in the therapy of patients with differentiated thyroid cancer (DTC); however, 5% to 15% of DTC and 50% of metastatic DTC are not amenable to radioactive iodine I131 therapy. Some patients suffer from recurrent disease after complex treatment. Recurrent disease is often resistant to radioiodine and shows a poor response to radioactive iodine therapy. The aim. To analyze the publications devoted to the problems of radioiodine-resistant thyroid cancer and their clinicopathological and molecular-genetic characteristics. Search strategy. The literature search was performed in the electronic databases Web of Science Core Collection, Scopus, Google Scholar over the past 5 years: from 2018 to 2023. Inclusion criteria were systematic reviews, original articles. Exclusion criteria were articles of poor methodological quality, duplication, missing or incomplete data in articles, case reports, letters, editorials, and expert opinions. 135 articles were found, of which 88 were selected for analysis. Results of the research. According to the material studied, special attention is now paid to the presence of driver mutations, such as telomerase reverse transcriptase promoter mutations TERT, BRAF V600E, NRAS, which show an aggressive genetic pattern; they can also be used for patient risk stratification when determining radioiodine resistance in patients. In addition, histological examination of the tumor is also one of the most important predictors of DTC prognosis. Conclusion. Based on the analysis of publications, we can conclude that significant progress has been made over the past decades in understanding the molecular mechanisms that cause the malignant evolution of DTC and the development of radioiodine resistance. Given the relationship between molecular and histological heterogeneity, the selection of tumor samples for molecular genetic analysis should be based on the results of histological evaluation of the entire tumor. Comprehensive molecular genetic analysis, as well as histological characteristics of the tumor, will subsequently play an important role in stratifying patients and determining further patient management tactics.