An 11-year longitudinal study sponsored by the National Cancer Institute has been halted 3 years early because its findings are particularly clear and striking: finasteride, a drug currently used primarily to fight baldness and enlarged prostates, reduces the chance that a man will develop prostate cancer by 25%.
Prostate cancer afflicts 221,000 American men each year, killing 29,000, and the only treatment is to remove part or all of the prostate which often leaves the patient impotent and incontinent. Finasteride drugs, such as Propecia and Proscar -- which are already approved for sale by the FDA -- could greatly reduce the number of men afflicted with this disease, saving thousands of lives per year and millions of dollars in medical costs.
Men with a history of prostate cancer in their family are particularly at risk for developing it themselves. There appear to be few side-effects to the treatment (except maybe growing more hair).
Update:
Allen Glosson posted a good deal more information in the comments section, go read it. He points out that there are several available treatments for prostate cancer other than surgical removal, but all of these generally lead to sterility and often to impotence and incontinence.
Reading the study more closely, while the overall risk of getting PCa went down for those using finasteride, those using that drug who did develop PCa got a more virulent strain of PCa. The study didn't note whether there is a connection between the drug and the more aggressive PCa.
Actually, there are other treatments, not just surgical removal. One is radioactive seed implantation into the prostate. This puts low dose radation directly onto the affected tumor areas. The half-life is typically on the order of a few weeks. Another is HDR (High Dose Radiation) which is like seeds, but the implantation is temporary. A map is made of the prostate, then a set of needs inserted into the prostate (under a local.) A sophisticated computer program determines into which needle to insert a high dose radiation source and for how long. This treatment is typically done over the course of a few days. Follow up treatments may or may not be necessary. Another is 3D EBRT. Unlike traditional radiation treatments, 3D External Beam Radiation Treatments attempt to determine the exact location of the tumor and focus exclusively on that area while at the same time, bypassing (or attempting to) the bladder and colon.
Another newer treatment is to use a benign virus, injected into the prostate, which attaches to and kill cancer cells.
(I could go on at length, but will cut myself short here. If you want to know more, please feel free to email.)
In all of these cases, sterility is pretty much a given, but the impotence and incontinence rates vary.
For all treatments, incontinence rates are in the single digit percentages while impotence is in the 40-60% range.
Of course, it's important to get a PSA and DRE test regularly after age 40, or if you have a family history of PCa (like runs in my family) immediately to establish a baseline.
As with any medical treatment, investigate your options thoroughly before deciding on a course of treatment.
Excellent information, thanks! My family has a history of prostate cancer as well, which is why I was glad to see the results of this study.
I haven't read the study itself, but the news article indicated that the rate of malignancy while taking finasteride may have been higher simply due to the significant number of non-malignant cancers that were prevented.
In any case, the results of the study are good news.
You might also examine Phoenix5 for more information. This site was set up by the late Robert Young and is now being continued by his widow, Caren.