As with so many medical warnings, be aware that these are worded with extreme caution. They do not differentiate between correlation and causation. Also, with prostate cancer, you should keep in mind that any man’s probability of having detectable prostate cancer is about equal to his age. That is, by age 60, about 60% of men have clinically detectable prostate cancer. By age 70, the percentage is about 70%, and so on. Just be aware that clinically detectable and clinically significant are not the same. Upon autopsy, many men are found to have prostate cancer, but small amounts of low-grade disease that would not have likely ever required any treatment.
My one caution about taking drugs like tamsulosin or finasteride is that if you are also monitoring PSA for prostate cancer detection or progression, starting one of these drugs can mask increases in PSA and make it difficult to track progression. A savvy urologist can manage, as there are models that help them adjust for the meds, but they need to be aware and take them into consideration.
How do I know these things? Experience. Had radiation treatment for prostate cancer about 4 years ago. . .