A Significance of Concomitant BRAFV600E and TERT Mutations in Polish Patients with Papillary Thyroid Microcarcinoma: A Retrospective Cohort Study Based on 430 Cases

Background: The incidence of papillary thyroid cancer is increasing worldwide due to more frequent pathological detection of papillary thyroid microcarcinomas (PTMC), which are cancers measuring 1 cm or less in diameter. In rare cases, the course of PTMC can be aggressive, with an increased risk of recurrence/persistent disease. The aim of this study of Polish patients diagnosed with PTMC was to assess the impact of concomitant B-type Raf kinas-activating mutation in codon 600 of exon 15 (BRAF(V600E)) and telomerase reverse transcriptase (TERT) hotspot mutations on clinicopathological features, response to treatment, potential recurrence, and the final outcome.Methods: A retrospective analysis of the 430 PTMC cases diagnosed during 2001-2020 at a single center was performed. All PTMC cases were assessed histopathologically, and analyses of BRAF(V600E) and TERT promoter were performed based on DNA isolated from tumor blocks.Results: There were 29/430 (6.7% [confidence interval: 4.6-9.5]) patients in whom the TERTC228T and/or TERTC250T mutations coexisted with the BRAF(V600E) mutation. A statistical comparison between PTMC cases with concomitant BRAF(V600E) and TERT hotspot mutations and those without any of those mutations revealed no significant differences between the two groups with respect to risk stratification, response to primary treatment, clinical course, or final disease status.Conclusion: Regardless of the molecular background of PTMC, the overall response to therapy is excellent, and long-term disease-free survival rates can be achieved by most patients.

Automated summary

This study examined the impact of BRAF(V600E) and TERT hotspot mutations on Polish patients with PTMC. Regardless of the presence of these mutations, the overall response to treatment and long-term disease-free survival rates were excellent.