Review of Genomic Drivers of Thyroid Cancer and Their Clinical Implications

Over the past several decades, rapid advances in molecular genomics have transformed our understanding of thyroid malignancies and are increasingly integrated into international clinical guidelines. Mutational profiles and epigenetic events are now recognized not only as diagnostic and prognostic tools but also as predictors of therapeutic response. Papillary, follicular, oncocytic, medullary, and anaplastic thyroid carcinomas harbor distinct early driver mutations, such as BRAFV600E, RAS, and fusion events (RET, NTRK, and ALK), that cooperate with secondary alterations (TERT promoter, TP53, PIK3CA, and CDKN2A/B loss) to drive dedifferentiation, metastasis, and therapeutic resistance. Insights from The Cancer Genome Atlas (TCGA) and transcriptomic scoring systems (e.g., BRAF–RAS score) now link genotype to tumor morphology, metastatic tropism, and radioactive iodine refractoriness. These molecular insights have been incorporated into updated risk stratification frameworks, preoperative surgical planning, and treatment algorithms, informing the selection of kinase inhibitors, redifferentiation strategies, and enrollment in genotype-directed clinical trials for radioiodine-refractory disease. This review synthesizes recent evidence connecting genomic alterations to clinical behavior and highlights their translation into evolving approaches for thyroid cancer management.