This case-control study was conducted between 2020 and 2023, in which n = 115 tumor tissues (NMIBC n = 85) and (controls n = 30) were examined for FGFR3 and FGFR promoter methylation and expression using methylation-specific PCR (MSP) and real-time PCR. This evidence concerns the gene FGFR3 and neoplasm.