Coexistence of Promoter Mutations and the V600E Alteration and Its Impact on Histopathological Features of Papillary Thyroid Carcinoma in a Selected Series of Polish Patients.

promoter (p) mutations are important factors in papillary thyroid carcinomas (PTCs). They are associated with tumor aggressiveness, recurrence, and disease-specific mortality and their use in risk stratification of PTC patients has been proposed. In this study we investigated the prevalence of p mutations in a cohort of Polish patients with PTCs and the association of these mutations with histopathological factors, particularly in coexistence with the V600E mutation. A total of 189 consecutive PTC specimens with known mutational status were evaluated. p mutations were detected in 8.5% of cases (16/189) with the C228T mutation being the most frequent. In six of the PTC specimens (3.2%), four additional p alterations were found, which included one known polymorphism (rs2735943) and three previously unreported alterations. The association analysis revealed that the p hotspot mutations were highly correlated with the presence of the V600E mutation and their coexistence was significantly associated with gender, advanced patient age, advanced disease stage, presence of lymph node metastases, larger tumor size, and tumor-capsule infiltration. While correlations were identified, the possibility of p mutations being key molecular modulators responsible for PTC aggressiveness requires further studies.