Environmental factors related to the origin and evolution of differentiated thyroid cancer: a narrative review.

The global incidence of thyroid cancer (TC) has increased in the last decades. While improvements in diagnosis may contribute, overdiagnosis is also a possibility. This review focuses on the epidemiology, risk factors, and immune microenvironment associated with differentiated TC (DTC). A search was conducted in Scielo, Scopus, and EMBASE databases, involving 72 articles. TC is the most common endocrine neoplasm, with DTC form being predominant. Its incidence has globally risen, particularly among women aged over 45. Endogenous risk factors for DTC include genetic disorders, race, age, female gender, obesity, and type 2 diabetes mellitus. Environmental risks involve ionizing radiation, whether through therapeutic treatment or environmental contamination from nuclear accidents, iodine deficiency, endocrine disruptors, residence in volcanic areas, environmental pollution, and stress. The use of anti-obesity medications remains controversial. The tumor's immune microenvironment is the histological space where tumor cells interact with host cells, crucial for understanding aggressiveness. Immunotherapy emerges as a promising intervention. Recent advances in DTC management offer transformative potential, requiring collaborative efforts for implementation. Emerging areas like precision medicine, molecular profiling, and immunotherapy present exciting prospects for future exploration, shaping the next era of diagnostic and therapeutic strategies in thyroid cancer research. The global incidence of thyroid cancer (TC) has significantly increased, attributed partly to improved diagnosis and potentially to overdiagnosis. This review focuses on the epidemiology, risk factors, and immune microenvironment associated with differentiated TC (DTC). DTC is the most common endocrine neoplasm, and predominantly affects women over 45 years old. Endogenous risk factors include genetic disorders, race, age, female gender, obesity, and type 2 diabetes mellitus (T2DM). Environmental risks encompass ionizing radiation, iodine deficiency, endocrine disruptors, volcanic residence, pollution, and stress. The use of glucagon-like peptide 1 agonists remains controversial. The tumor’s immune microenvironment is crucial for understanding aggressiveness, with immunotherapy showing promise. Understanding both macro and microenvironmental factors is crucial for devising effective prevention and treatment strategies for DTC.