Bladder Tumors: Molecular Aspects and Clinical Management

Bladder cancer is a common cancer of the urinary tract. It is the fourth leading cause of cancer-related death among men and the seventh among women. Clinical management of bladder cancer is challenging because of the heterogeneity among bladder tumors with respect to invasion and metastasis, frequent occurrence of new tumors in the bladder among patients treated with bladder preservation treatments and poor prognosis of patients with tumors that invade the bladder muscle and beyond. Due to these factors it has been said that the cost per patient of bladder cancer, from diagnosis to death is the highest of all cancers. In addition to it being a significant health problem, bladder cancer is an interesting cancer to study in many ways than one. For example, Environmental factors such as cigarette smoking and other carcinogens play a major role in the development of transitional carcinoma of the bladder, whereas, schitosomasis, a protozoan infection results in squamous cell carcinoma of the bladder. Different molecular pathways with distinct molecular signatures appear to be involved in the development of low-grade versus high-grade bladder tumors. Currently being monitored by an invasive endoscopic procedure, cystectomy, with urine cytology as an adjunct, bladder cancer is at the forefront of developing cancer biomarkers for non-invasive detection. Due to the differences in the invasive and metastatic potential of bladder tumors, treatment options differ depending upon tumor grade and stage. New advances are being made in treatment options to improve the outcome and quality of life for patients with bladder cancer. Similarly, new molecular nomograms are being discovered to predict treatment outcome so that individualized treatment options can be offered to patients.