Bladder cancer accounts for approximately 90% of cancers of the urinary tract and the incidence increases with age. People over the age of 70 develop the disease, two to three times more often than those aged 55-69. Male: female ratio of bladder cancer is 3:1. The highest frequency of bladder cancer in the world is in Egypt due to the endemic schistosomiasis. Tumors that develop in the bladder are classified into low-stage (superficial) or high-stage (muscle invasive). Superficial tumors can be "shaved off" or they can be treated by chemotherapy. On the other hand, cystectomy or a combination of radiation and chemotherapy must be used in muscle invasive tumors.
Bladder cancer usually result from somatic mutations that develops in certain bladder cells. Fibroblast growth factor receptor 3 (FGFR3), V-Ha-Ras Harvey rat sarcoma viral (HRAS) oncogene homolog, retinoblastoma 1 (RB1), and tumor protein p53 (TP53) are the genes associated with bladder cancer. These genes play an important role in regulating the cell division cycle and preventing cells from dividing too rapidly or in an uncontrolled manner. The most common risk factors for developing genetic mutations are smoking and exposure to industrial chemicals. Family history of bladder cancer is another known risk factor, although bladder cancer is not inherited.