Background:Papillary thyroid carcinoma (PTC) is the most common type of thyroid cancer.TheRETgene rearrangementsCCDC6::RETandNCOA4::RETare the most commonRETgene rearrangements in PTC patients. DifferentRET::PTCrearrangements are associated with different PTC phenotypes.Methods:Eighty-three formalin-fixed paraffin-embedded (FFPE) PTC samples were examined. The prevalence and expression levels ofCCDC6::RETandNCOA4::RETwere determined using semi-quantitative polymerase chain reaction (qRT-PCR). The association of these rearrangements with clinicopathological data was investigated.Results:The presence ofCCDC6::RETrearrangement was significantly associated with the classic subtype and absence of angio/lymphatic invasion (p< 0.05). WhileNCOA4::RETwas associated with the tall-cell subtype, and presence of angio/lymphatic invasion and lymph node metastasis (p< 0.05). Multivariate analysis demonstrated that an absence of extrathyroidal extension and extranodal extension were independent predictive factors forCCDC6::RET, whereas the tall-cell subtype, large tumor size, angioinvasion, lymphatic invasion and perineural invasion were independent predictive factors forNCOA4::RET(p< 0.05). However, the mRNA expression level ofCCDC6::RETand ofNCOA4::RETwere not significantly associated with clinicopathological data.Conclusion:CCDC6::RETwas correlated with an innocent PTC subtype and characteristics, butNCOA4::RETcorrelated with an aggressive phenotype of PTC. Therefore, theseRETrearrangements strongly associated with clinicopathological phenotypes and can be used as predictive markers in PTC patients.