Fritz H. Schröder, professor and chair of the Department of Urology, Erasmus University, Rotterdam, said that doctors should explain why prostate screening has divided the medical profession. He added, "Testing without providing this information is unethical."
Prostate cancer mostly affects men over the age of 65, most of whom usually die of something else, without even knowing they have it - very few die from the disease itself. But in 1996, prostate cancer accounted for 55,704 deaths in the European Union. After lung and colon cancer, it is the third most common cause of cancer death among men in the UK.
The blood test measures a substance called protein specific antigen (PSA) made by the prostate. Generally speaking, the higher the PSA level, the greater the chance of cancer. But some men with prostate cancer do not have high PSA levels. Conversely, two thirds of men with higher levels of PSA do not have prostate cancer. Non-malignant conditions involving enlargement or infection or inflammation of the prostate are also associated with high PSA levels.
Professor Schröder said that if even if ongoing screening studies were shown to reduce mortality, there would still be important outstanding questions, such as:
- How can anxiety and painful removal of tissue (for biopsy) be avoided in men who have an abnormal PSA test but no cancer?
- How can the diagnosis of less or non-harmful cancers by avoided?
- What is the impact of early diagnosis and aggressive treatment on quality of life?
- Is the balance right between benefit and harm?
At present, treatment options when the disease has not spread to other parts of the body include surgical removal of the prostate; radiation therapy or "watchful waiting", in which PSA levels are monitored periodically, and the cancer is only actively treated if it grows quickly or causes problems. Research has yet to establish if one option is better than another, but the availability of testing in the USA led to a large increase in "radical prostatectomy", and to greater use of radiotherapy.
Professor Schröder said that besides issues such as quality of life after treatment in relation to the risk of disease, the side effects of treatment and the definition of "watchful waiting" were all "tightly connected to the question of whether screening should become health care policy”.
He concluded: "Obviously, only the availability of (research) data will allow a complete risk benefit and cost analysis. We hope all these questions can be answered positively so that we can finally introduce a preventive measure into one of the most important disease entities of the male population.
"Meanwhile, powerful, early diagnostic tests cannot be withheld from well informed men. The accent here, however, has to be on well informed".
Abstract No. 1360
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