Telomerase Reverse Transcriptase Promoter Alterations Across Cancer Types as Detected by Next-Generation Sequencing: A Clinical and Molecular Analysis of 423 Patients

BACKGROUND: Telomerase reverse transcriptase (TERT) promoter mutations that may affect telomerase activity have recently been described in human malignancies. The purpose of this study was to investigate the clinical correlates of TERT promoter abnormalities in a large cohort of patients with diverse cancers. METHODS: This study analyzed TERT promoter alterations and clinical characteristics of 423 consecutive patients for whom molecular testing by next-generation sequencing was performed between August 2014 and July 2015. RESULTS: Of the 423 patients, 61 (14.4%) had TERT promoter mutations, and this placed TERT promoter alterations among the most prevalent aberrations after tumor protein 53 (TP53; 39%) and KRAS and cyclin-dependent kinase inhibitor 2A/B (CDKN2A/B) alterations (15% each) in this population. TERT promoter alterations were more frequent in men (P=.031) and were associated with brain cancers (P=.001), skin cancers/melanoma (P=.001), and a higher number of aberrations (P=.0001). A co-alteration analysis found that TERT promoter alterations were significantly correlated with CDKN2A/B (P=.001) and BRAF abnormalities (P=.0003). Patients harboring TERT promoter alterations or TP53 or CDKN2A/B alterations and those with 4 or more alterations demonstrated shorter survival (hazard ratio for normal TERT promoters vs aberrant ones, 0.44; P=.017). However, only a higher number of alterations remained significant in the multivariate analysis. CONCLUSIONS: Overall, TERT promoter alterations were among the most prevalent aberrations in this population, with very high rates in brain cancers (48% of patients) and melanomas (56% of patients). These aberrations frequently coexist with a high number of other aberrations, with the latter feature also significantly associated with poorer overall survival. Therapeutic options for targeting tumors with TERT promoter mutations are currently limited, although a variety of novel approaches are under development.