In the control group, of the 24 urinary bladder exfoliated cell samples submitted to cytological analysis from patients (median age of 61.4, ranging from 26 to 82 years) with negative diagnosis for cancer (four of them with cystitis), 2/23 (8.3%) and 8/16 (50%) exhibited RARB and RASSF1A hypermethylation, respectively. This evidence concerns the gene RASSF1 and chronic cystitis.