Bladder Cancer

Epidemiology of Cancers: Bladder Cancer

Description
Transitional cell carcinomas (TCC) - In industrialized countries TCC account for over 90% of malignant tumours of the urinary bladder.

Nontransitional cell carcinomas - include squamous cell carcinomas, adenocarcinomas, and undifferentiated carcinomas and account for 5-7% of bladder cancers.

In developing countries an estimated 75% of cases are squamous cell carcinomas caused by infection with Schistosoma haematobium.

Symptoms
Haematuria (usually painless) - primary symptom of bladder cancer.
Frequent urination.
Dysuria.

Epidemiology

  • The highest incidence rates are reported in North America and Western Europe and the lowest in Asia.
  • In the UK bladder cancer is the 4th most common cancer among men. In 2002 of a total of 10,199 newly diagnosed cases of bladder cancer, 7,275 occurred among males compared with 2,924 among women giving a male to female ratio of 2.5:11.
  • Moderate increases in incidence have been observed in industrialized countries in the last few decades2.
  • In the UK age standardised incidence rates increased throughout the 1970s and 1980s reaching a peak in the late 1980s. Most of this increase occurred in older age groups especially among persons born before the 1920s1.
  • Bladder cancer increases with increasing age with most cases occurring among persons aged over 50 years.
  • In 2004 there were 4,816 deaths in the UK from bladder cancer. Age standardised mortality rates among men were 8.4/100,000 male compared with 2.9/100,000 among women. Over 90% of female deaths and 88% of male deaths occurred in persons aged over 65 years.
  • Between 1992 and 2004 males rates of bladder cancer fell by 30% and was most marked in the 50-59 year age group.
  • Population based survival rates increased from 40% in the early 1970s to 58-67% in the late 1980s. These increases have been most marked among men1.
  • The five-year survival rates for persons with superficial tumours - 89-90%, compared with <50% with muscle invasive bladder cancer1.

Risk Factors

  • Smoking - is the most important risk factor for the development of bladder cancer and is involved in the aetiology of an estimated 30-50% of bladder cancers.
  • Age - increases significantly with age.
  • Sex - 2-3 times more prevalent among males.
  • Occupational exposure to industrial carcinogens, especially b-naphthylamine which was used in the manufacturing of dyes and the rubber industry in the 1950s.
  • Cyclophosphamide and other chemotherapy drugs.

Screening and Prevention
No screening programme for bladder cancer is currently available in the UK.
Smoking cessation.

References

  1. Cancer Research UK.
  2. Adami, HO, Hunter D, Trichopoulos D, eds. Textbook of Cancer Epidemiology, Oxford University Press: New York, 2002.

© CM Kirwan 2006