TERT promoter mutations and the outcome of patients with advanced urothelial carcinoma treated by platinum-based chemotherapy or pembrolizumab.

Background: TERT promoter mutation is one of the most common genomic alterations in urothelial carcinoma (UC). Its prognostic role on patients' outcomes is still not clear.Methods: We performed a single-center retrospective analysis on patients with advanced UC treated with platinum-based chemotherapy or immunotherapy to assess the presence of somatic TERT- 124[C>T] and TERT-146 [C>T] mutations and their association with clinicopathologic factors and survival outcomes. Patients were assessed for Overall Survival (OS), Progression-Free Survival (PFS), and Overall Response Rate (ORR).Results: We analyzed 45 UC tumors; 38 of them received first-line chemotherapy and 21 second-line pembrolizumab; 6 patients (13%) harbored -146 C > T TERTp mutation and 25 patients (56%)-124 C > T. The presence of TERT promoter mutations was associated with a higher rate of lower tract UC and a lower rate of synchronous or lymph node metastases. TERT wild-type patients showed higher 12- and 24-months OS-rates in the chemotherapy subgroup and 6-, 12- and 24-months OS rates in the pembrolizumab subgroup. The presence of TERT promoter mutations was also associated with a lower 6 months-PFS rate in patients receiving chemotherapy and in all the three time points in those treated by pembrolizumab. The ORRs of pembrolizumab were 21% and 71% in patients with or without TERT promoter mutations, respectively (p < 0.001). Conclusions: Our analysis suggests that the presence of TERT promoter mutations could negatively affect the outcome of UC patients treated by chemotherapy or pembrolizumab. This hypothesis should be further evaluated in wider cohorts.