[Molecular classification of bladder cancer. Possible similarities to breast cancer]

Therapeutic decisions for breast cancer are increasingly becoming based on subtype-specific gene expression tests. For bladder cancer very similar subtypes have been identified by genome-wide mRNA analysis, which as for breast cancer differ with respect to the prognosis and response to therapy on the basis of their hormone dependency. At the DNA level, however, the type of mutations and their frequencies within the subtypes are strikingly different between bladder and breast cancers. It will be interesting to see whether possible driver mutations can serve as therapeutic targets in both indications. In contrast, the apparent hormone dependency of a substantial number of bladder carcinomas suggests that hormonal and anti-hormonal treatment can be valid therapy options similar to breast cancer. Moreover, gender-specific differences with respect to the incidence and aggressiveness of male compared to female bladder cancers can be explained by hormonal effects. Together with forthcoming immunomodulatory therapies these multiple therapy options raise and give new hope to efficiently combat this aggressive disease.