TERT promoter mutations in soft tissue sarcomas.

Introduction: Oncogenic hotspot mutations in the promoter region of the TERT gene have been identified in several cancer types as being associated with a worse outcome. Additionally, a polymorphism (rs2853669) in the TERT promoter region was reported to modify the survival of TERT-mutated patients. Our aim is to determine the frequency of c.-124 C>T and c.-146 C>T TERT mutations and to genotype the rs2853669 polymorphism in a series of 68 soft tissue sarcomas (STS) comprising 22 histological subtypes.

Methods: PCR was performed, followed by direct sequencing of a fragment of TERT containing the hotspots and the rs2853669.

Results: We found TERT mutations in 4/68 (5.9%) STSs including 1 pleomorphic liposarcoma (1/1), 1 dedifferentiated liposarcoma (1/1) and 2 myxoid liposarcomas (2/9). The variant C allele of rs2853669 was found in 54.8% (34/62) of all STSs and in 75% (3/4) of TERT-mutated cases. TERT mutations were associated with younger age, and the C allele of the rs2853669 was associated with high histological grade (2 and 3). No association was found between TERT mutation status or rs2853669 genotype and patient prognosis.

Conclusions: We showed that TERT promoter mutation is not a recurrent event in STS and is present in particular histological subtypes.