Microsatellite instability in multifocal urothelial carcinoma and effect on BAX and AXIN2.

Objectives: Urothelial carcinomas have a synchronous or metachronous multifocal pattern of occurrence, questioning their clonal origin. Genetic alterations such as microsatellite instability (MSI) affect various tumors including urothelial cancers. These alterations can affect repeat sequences and cause mutations in coding regions of genes involved in transformation, tumor suppression and apoptosis.