Bladder cancer is often first noticed as painless blood in the urine
Each year about 500,000 people learn they have bladder cancer, most after spotting blood in their urine without any pain. Tobacco smoking causes roughly half of all cases, and the average age at diagnosis is 73. How far the tumour has spread when it is found largely shapes what follows.
Visible blood, known as haematuria, shows up in around 75 percent of people eventually diagnosed; others have traces seen only under a microscope, or no symptoms whatsoever. Most people with blood in their urine do not have the disease: it turns up in up to 22 percent of those with visible blood and 5 percent of those with microscopic traces. Women with bladder cancer are often misdiagnosed with urinary tract infections at first. Besides smoking, certain toxic chemicals and the tropical infection schistosomiasis raise the risk, and around 200,000 people die of the disease each year.
The standard investigation is cystoscopy, in which a thin flexible camera is passed through the urethra into the bladder. It spots finger-shaped papillary tumours well but misses small flat ones more easily; in blue light cystoscopy, a dye that gathers in cancer cells glows under blue light, making small growths easier to see. Suspicious tissue is cut out in the same procedure, along with a sliver of underlying muscle, and examined by a pathologist. Urine cytology, which looks for shed cancer cells, catches about two thirds of high-grade tumours but only 1 in 8 low-grade ones.
Over 90 percent of tumours begin in the urothelial cells lining the bladder. Cases are staged from 0 to 4 with the TNM system, which scores the depth of the original tumour, spread to lymph nodes and spread to distant organs. About 75 percent are still confined to the bladder at diagnosis, around 18 percent have reached the muscle wall, and about 3 percent have already travelled to distant sites, most often the bones, lungs, liver and lymph nodes.
Tumours that have stayed within the bladder are usually removed surgically, followed by chemotherapy or immune-stimulating treatment. One such approach puts the BCG vaccine, long used against tuberculosis, into the bladder weekly for six weeks, which nearly halves recurrence. When tumours keep growing or invade the muscle, surgeons often remove the entire bladder. People whose cancer has spread beyond it survive about a year on average from diagnosis.
Source: Bladder cancer
