Posted 8/28/2010 11:50 PM (GMT 0)
This is a complex issue, because there really isn't adequate information for a completely rational decision. Here are some facts:
1. The rate of prostate cancer deaths was going up steadily in the 1980's, and reached 40/100,000 per year by 1990. In the early 1990's it leveled off, then it started falling, and was down to 25/100,000 by 2006. The corresponds to the time that PSA screen was introduced.
2. It isn't know what caused this very significant decrease in prostate cancer deaths. Is it the result of PSA screening? Is it because men with advanced prostate cancer are better treated and live to die of something else? Is it because of surgical or radiation treatment of earlier prostate cancer? Is there some other, unrelated environmental factor?
3. There is a controlled randomized study of prostate surgery versus watchful waiting, with 12 years of followup, with the patients mostly having intermediate prostate cancer detected by rectal exam,which shows that there is a modest decrease in death rate with surgery for these patients, but no decrease in death rate when the patients were over 65 at the time of diagnosis.
4. As mentioned before, many, many middle aged and old men have microscopic prostate cancer, which has been described at autopsy if they die for some reason other than prostate cancer. This is different from the men who get diagnosed with prostate cancer when they are still alive, because those men usually have an elevated PSA, and a lump of cancer cells big enough to hit with a biopsy needle.
5. There are lots of ways to assess how bad someone's prostate cancer at diagnosis, including PSA, PSA doubling time, Gleason score, % of biopsy positive for cancer, color doplers, etc, etc. None of these are perfect. All of these tests can help predict the chance of someone eventually dying from prostate cancer, but none of them can tell you than chance is 0. For example, even with a Gleason score of 6, the chance of dying of prostate cancer in the next 12 years is 8%.
6. Only about 12% of people who get prostate cancer will die from it: In 2010-- New cases: 217,730; Deaths: 32,050
7. No question that a lot of men receive prostate surgery or radiation where either 1. they would never die or prostate cancer anyway or 2. (in a small number of cases) they will still die from prostate cancer despite the treatment. For example, googling this topic, I found that in 2002 the number of prostatectomy procedures were 195,000 in the US. So there is a lot of surgery done to save a modest number of lives. http://answers.google.com/answers/threadview?id=367638
8. Prostate cancer treatment has significant side effects, read this forum for details.
9. Much prostate cancer is very slow growing, you may have to live 15, 20, or 25 years for there to be any chance of the surgery saving your life.
My take on all this:
1. Many prostate cancers are very early at the time of diagnosis. The treatment, surgery or radiation, has an excellent chance of getting rid of it. However, there is an excellent chance that nothing too bad would happen in the next 10 or 15 years, anyway, even if you don't treat it. If you are in this group, and you plan on living longer than 10 or 15 years, there is a low to modest chance of dying from prostate cancer if you don't treat it.
2. Prostate cancer surgery or radiation likely won't improve life expectancy if you are older, maybe older that 70 or late 60s.
3. If you have advanced prostate cancer, surgery or radiation are unlikely to improve your life expectancy.
4. If you intermediate prostate cancer, and are over 65, prostate surgery or radiation are unlikely to improve your life expectancy.
5. If you have intermediate prostate cancer, and are under 65, prostate surgery or radiation will modestly increase your chance of living longer.
6. The best data on outcomes are for prostate surgery. The studies on radiation and other treatments are less definitive.
7. There is no group where prostate treatment has a high chance of saving lives.
If you say that too many people are being treated for prostate cancer, since it will, overall, only save the lives of a small portion of the people treated, you'd be correct. If you think that we can always predict who should and who should not get treated, you'd be overstating what is known. The test results at diagnosis are a clue. The life expectancy of the person is another important clue. The third fact is the consequences of the treatment. If the treatment has a big negative effect on quality of life, the possible benefit has to be high to justify it, and this is not the case for most, prostate cancers.