[Epidemiology of prostatic cancer]

Prostate cancer is the most common type of cancer in Norway, with more than 2,400 new cases each year. Hormones, diet, and chemical and genetic factors are implicated in the aetiology. It is not clear whether alcohol and tobacco increase the risk of prostate cancer. Median age at diagnosis is 74-75 years. The incidence has increased steadily with a doubling of the number of cases over 20-25 year periods. Prostate cancer mortality in Norway is the highest among the Nordic countries and among the highest in the world. Five-year relative survival for all cases combined is 60%. Approximately 55-60% of the patients dies from the disease. The incidence is lower in the three northernmost counties. Elsewhere in the country the incidence varies between counties according to variations in diagnostic practice. Serological analysis of Prostate Specific Antigen after 1990 has lead to an increase in the number of new cases, mainly because of earlier diagnosis. Prostate cancer is often a slowly growing tumour which is clinically asymptomatic for many years. Latent carcinoma is found at autopsy in 30-35% of men above 50 years of age. Today, prevention of prostate cancer is not feasible, though specific advice about life style and diet might decrease the risk.