Auxiliary diagnostic value of p16 amplification combined with the detection of heterozygous and homozygous loss for urothelial carcinoma.

The present study aimed to investigate the significance of detecting cyclin dependent kinase inhibitor 2A (p16) gene aberrations in the diagnosis of urothelial carcinoma (UC) using fluorescence in situ hybridization (FISH). A total of 77 voided urine specimens from 65 patients with UC and 12 patients with benign urinary disease were recruited into the current study. Under a fluorescence microscope, cells with large and irregular nuclei were assessed for chromosomal aberrations. The positive rate of p16 amplification in UC samples was 32.3% (21/65), which was significantly higher than that in benign urinary disease samples (16.7%, 2/12; P<0.05). Heterozygous and homozygous loss of p16 was identified in 12 (18.5%) and 23 (35.4%) patients with UC, respectively; p16 expression in the remainder of patients was normal. In addition, as tumor stage or grade advanced, the positive rate of p16 aberrations also increased significantly (P<0.05). In conclusion, p16 gene aberrations may serve important roles in the auxiliary diagnosis of UC by FISH and could be utilized to monitor UC progression.