TERT Copy Number Alterations, Promoter Mutations and Rearrangements in Adrenocortical Carcinomas

AbstractMolecular characterization of adrenocortical carcinomas (ACC) by The Cancer Genome Atlas (TCGA) has highlighted a high prevalence ofTERT alterations, which are associated with disease progression. Herein, 78 ACC were profiled using a combination of next generation sequencing (n = 76) and FISH (n = 9) to assess forTERT alterations. This data was combined with TCGA dataset (n = 91). A subset of borderline adrenocortical tumors (n = 5) and adrenocortical adenomas (n = 7) were also evaluated. The most common alteration involving theTERT gene involved gains/amplifications, seen in 22.2% (37/167) of cases. In contrast, “hotspot” promoter mutations (C >  T promoter mutation at position -124, 7/167 cases, 4.2%) and promoter rearrangements (2/165, 1.2%) were rare. Recurrent co-alterations included 22q copy number losses seen in 24% (9/38) of cases. Although no significant differences were identified in cases with and withoutTERT alterations pertaining to age at presentation, tumor size, weight, laterality, mitotic index and Ki67 labeling, cases withTERT alterations showed worse outcomes. Metastatic behavior was seen in 70% (28/40) of cases withTERT alterations compared to 51.2% (65/127,p = 0.04) of cases that lacked these alterations. Two (of 5) borderline tumors showed amplifications and noTERT alterations were identified in 7 adenomas. In the borderline group, 0 (of 4) patients with available follow up had adverse outcomes. We found thatTER...
Source: Endocrine Pathology - Category: Pathology Source Type: research