RT info:eu-repo/semantics/article T1 TERT amplification a risk stratification marker in papillary thyroid carcinoma, significantly correlated with tumor recurrence and survival A1 Gil Bernabé, Sara A1 Feás Rodríguez, Noa A1 Pérez Riesgo, Enrique A1 Corraliza Gómez, Miriam A1 Fra Rodríguez, Joaquín A1 García-Rostán y Pérez, Ginesa María K1 TERT amplification K1 Thyroid cancer K1 Metastases K1 Prognosis K1 Tumor recurrence K1 Survival K1 32 Ciencias Médicas AB Few studies have analyzed the prevalence of TERT amplification in thyroid cancer, showing discrepancies in various top-ics. The impact on tumor recurrence and patient survival in papillary thyroid carcinoma (PTC) remains unknown. Thirteencancer cell lines and 215 tumor samples from 91 patients, who underwent surgery for PTC (41), poorly differentiated thyroidcarcinoma (PDC = 15), or anaplastic thyroid carcinoma (ATC = 35), were analyzed. Clonality, spread with tumor dediffer-entiation or metastatic PTC cells, and coexistence with TERTp, BRAF, RAS, and PIK3CA mutations were also investigated.TERT amplification was found in 17%, 20%, and 17% of the PTC, PDC, and ATC, respectively. It was more frequent infollicular variant PTC and PTC with distant metastases (86%, P = 0.0448). The cell lines HTh74, SW1736, and T242 hadamplification. In PTC, TERT amplification was a subclonal event. The increase in TERT copy number spread in all cases withmetastatic PTC cells. In 67% of the PDC and 100% of the ATC, TERT activation segregated with tumor dedifferentiation.TERT amplification correlated with TERTp mutations in PTC (P = 0.0313) and PIK3CA mutations in ATC (P = 0.0272).TERT amplification significantly correlated with vascular invasion (P = 0.03637), distant metastases at diagnosis and/orfollow-up (P = 0.04482), metachronous distant metastases (P = 0.03131), death patient status (P = 0.000829), stage at diag-nosis (P = 0.01995), and stage III/IV at last follow-up (P = 0.01552). TERT amplification associated independently withtumor-related recurrence and death. Our study shows that PTC can be stratified into clinically prognostic relevant categoriesbased on the presence or not of TERT amplification in the cells. PB Springer SN 1046-3976 YR 2025 FD 2025 LK https://uvadoc.uva.es/handle/10324/75937 UL https://uvadoc.uva.es/handle/10324/75937 LA eng NO Endocrine Pathology, 2025, vol. 36, n. 1. NO Producción Científica DS UVaDOC RD 11-ago-2025