Bladder cancer (urothelial carcinoma) is the most common tumor of the urinary tract. It occurs more frequently among men about 65 years old on average. Two forms of the tumor are known: a non–muscle-invasive one and a muscle-invasive one. The latter turns out to be very aggressive with a survival of 5 years average. The non–muscle-invasive form frequently recurs (60–70%) and in 15% of cases, it progresses into the invasive form. The diagnosis is made mainly by cystoscopy and urine cytology. A high number of researches were dedicated in order to find a simple test using voided urine to frequently monitor possible tumor recurrence. During the last 10 years, many tests were proposed concerning either special proteins of which the most common are the bladder tumor antigen (BTA) and the nuclear matrix protein 22 (NMP22) or the presence of genetic mutations [most frequently, fibroblasts growth factor receptor 3 (FGFR3) and TP53], alteration of DNA methylation, chromatin structure and, more recently, the presence of specific micro-RNA. Recently the analysis of lipids present in voided urine showed a difference in fatty acids between healthy individuals and those affected by non-invasive forms. These markers appear to have a high specificity and sensitivity: a deepening of these results could lead to the development of a test that avoids invasive treatment and the cost of cystoscopy.
Part of the book: Bladder Cancer