EAU 2019: TERT Promoter and FGFR3 Mutations – A Highly Sensitive and Non-invasive Tool for Bladder Cancer Recurrence Detection

Barcelona, Spain (UroToday.com) Up to 3/4 of non-muscle invasive bladder cancer (NMIBC) patients will endure recurrence during their lifetime. Disease follow up is invasive, costly and long and consists of cystoscopy, cytology, and imaging. The most prevalent non-invasive approach for the diagnosis of recurrence remains urinary cytology, although far from ideal with reduced sensitivity and specificity.   In this study, based on the molecular profile of bladder cancer, the authors developed a non-invasive urinary assay for urothelial bladder cancer detection. Their aim was to clinically validate this novel assay in a multicenter prospective study.

This was a multicenter prospective study including NMIBC patients who were under routine follow-up. A total of 122 patients were included. As part of their follow-up, patients received cystoscopy, urine cytology and TURBT (if required [n=31]). For the purpose of this study, at the time of cystoscopy and/or cytology, patients were screened for TERT promoter and FGFR3 mutations in cells present in the urine by using a collection kit and real-time Polymerase chain reaction (PCR). The study’s endpoint was the detection rate of bladder cancer recurrence confirmed by histology during follow-up. Sensitivity and specificity were determined according to the pathology results and compared with cytology and cystoscopy findings.

Real-time PCR detection (Mut) performance in comparison with cystoscopy (Cys) and cytology (Cyt) in recurrence (Rec) are shown in figure 1. The sensitivity and specificity of real-time PCR were demonstrated to be 80.6% and 93.4%, respectively. These results were significantly better than the ones reported for cystoscopy and cytology (Figure 1). Real-time PCR performance in recurrence detection across tumor all stages and grades is shown in figure 2. These results show that the detection rate of low-grade bladder cancer was 100% with real-time PCR and only 25% with cytology.

In conclusion, the authors suggest that real-time PCR for TERT promoter and FGFR3 mutations appears to be a useful tool that can be used in NMIBC follow-up with impressive specificity and sensitivity for disease recurrence across various stages and grades, outperforming cytology. The results of this study are very interesting and there is a need for a larger prospective cohort to validate these results, before considering a clinical application on a regular basis.

Figure 1 – Real-time PCR detection performance in comparison with cystoscopy and cytology in bladder cancer recurrence:

EAU 2019 fig 1 real time PCR detection

Figure 2 - Real-time PCR performance in recurrence detection across tumor staging and grade

EAU 2019 fig 1 real time PCR performance

Presented by: Ricardo Leão, MD, Hospital de Braga, Braga, Portugal

Written By: Hanan Goldberg, MD, Urologic Oncology Fellow (SUO), University of Toronto, Princess Margaret Cancer Centre @GoldbergHanan at the 34th European Association of Urology (EAU 2019) #EAU19, conference in Barcelona, Spain from March 15-19, 2019.