BRAFV600E and TERT promoter mutations in paediatric and young adult papillary thyroid cancer and clinicopathological correlation

Abstract

AbstractObjectivesThe primary objective of this study was to determine the prevalence ofBRAFV600EandTERTpromoter mutations in paediatric and young adult patients with papillary thyroid carcinoma (PTC) and the secondary objective, to assess their association with clinicopathological features.MethodsPatients ≤20 years who underwent surgery for differentiated thyroid cancer (DTC) from 2005 to 2018 were consecutively enrolled forBRAFV600EandTERTpromoter mutations analysis and records analysed for the association of aggressive features. Univariate analysis and multivariate logistic regression were used to identify the independent predictors ofBRAFV600Emutations.ResultsAmong 100 patients with DTC, 68 patients were ≤18 years and the remaining 30 patients were >18 years of age with a median age of 17 years (IQR 14–19 years) 98 patients had PTC and 2 had FTC.BRAFV600Emutation was present in 14/98 (14.3%) PTC andTERTpromoter mutation noted in none. Multivariate analysis identified RAI refractoriness (OR:10.57, 95% CI: 2.6 to 41.6, P-0.0008) as an independent factor associated withBRAFV600Emutation. 17 patients with distant metastases were negative for bothBRAFV600EorTERTpromoter mutation. No significant association was observed between age, gender, PTC variants, extra-thyroidal extension, lymphovascular invasion, multifocality, RAI administration and event rate withBRAFV600Emutation. Irrespective ofBRAFV600Emutation, radioiodine refractory status (p-0.0001) had a reduced EFS probability.ConclusionIn paediatric & young adult PTC,TERTpromoter mutation is absent andBRAFV600Emutation is not associated with distant metastasis. The prevalence rate of theBRAFV600Emutation is much lower compared to adult PTC patients.