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Bladder cancer

Bladder cancer refers to any of several types of malignant growths of the urinary bladder. It is a disease in which abnormal cells multiply without control in the bladder.[1] The bladder is a hollow, muscular organ that stores urine; it is located in the pelvis. The most common type of bladder cancer begins in cells lining the inside of the bladder and is called transitional cell carcinoma (sometimes urothelial cell carcinoma).

Signs and symptoms

Bladder cancer characteristically causes blood in the urine; this may be visible to the naked eye (gross hematuria) or detectable only by microscope (microscopic hematuria). Other possible symptoms include pain during urination, frequent urination (polyuria) or feeling the need to urinate without results. These signs and symptoms are not specific to bladder cancer, and are also caused by non-cancerous conditions, including prostate infections and cystitis. Kidney cancer also can cause hematuria.

Causes

Tobacco smoking is the main known contributor to urinary bladder cancer: in most populations, smoking is associated with over half of bladder cancer cases in men and one-third of cases among women.

There is a linear relationship between smoking and risk, and quitting smoking reduces the risk.[3] Passive smoking may also be involved.[4] In a 10-year study involving almost 48,000 men, researchers found that men who drank 1.5L of water a day had a significantly reduced incidence of bladder cancer when compared with men who drank less than 240mL (around 1 cup) per day. The authors proposed that bladder cancer might partly be caused by the bladder directly contacting carcinogens that are excreted in urine, although this has not yet been confirmed in other studies.[5] Thirty percent of bladder tumors probably result from occupational exposure in the workplace to carcinogens such as benzidine. 2-Naphthylamine, which is found in cigarette smoke, has also been shown to increase bladder cancer risk. Occupations at risk are bus drivers, rubber workers, motor mechanics, leather workers, blacksmiths, machine setters and mechanics.[6] Hairdressers are thought to be at risk as well because of their frequent exposure to permanent hair dyes. A 2008 study commissioned by the World Health Organisation concluded that "specific fruit and vegetables may act to reduce the risk of bladder cancer."[5] Fruit and yellow-orange vegetables, particularly carrots and selenium,

[7] are probably associated with a moderately reduced risk of bladder cancer. Citrus fruits and cruciferous vegetables were also identified as having a possible protective effect.

It has been suggested that mutations at HRAS, KRAS2, RB1, and FGFR3 may be associated in some cases.

Diagnosis

The gold standard for diagnosing bladder cancer is biopsy obtained during cystoscopy. Sometimes it is an incidental finding during cystoscopy.[9] Urine cytology can be obtained in voided urine or at the time of the cystoscopy ("bladder washing"). Cytology is very specific (a positive result is highly indicative of bladder cancer) but suffers from low sensitivity (inability of a negative result to reliably exclude bladder cancer). There are newer urine bound markers for the diagnosis of bladder cancer. These markers are not currently used routinely in clinical practice due to absence of clear professional guidelines. They are much more expensive as well.[citation needed]

The diagnosing of bladder cancer can also be done with a Hexvix guided fluorescence cystoscopy (Hexvix®), as an adjunct to conventional white-light cystoscopy. This procedure improves the detection of bladder cancer and reduces the rate of early tumour recurrence, compared with white-light cystoscopy alone. Hexvix cystoscopy detects more cancer and reduce recurrency. Hexvix is marketed in USA under the brand name Cysview[10] [11]

Many patients with a history, signs, and symptoms suspicious for bladder cancer are referred to a urologist or other physician trained in cystoscopy, a procedure in which a flexible tube bearing a camera and various instruments is introduced into the bladder through the urethra. Suspicious lesions may be biopsied and sent for pathologic analysis.

Pathological classification

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