Does Propecia Cause Prostate Cancer?

I would like to know if there are further studies on Propecia to rule out if Propecia does or does not have a long term effect on causing prostate cancer.

Propecia (finasteride) is a blocker of the enzyme 5-alpha reductase. The mechanism of action of this enzyme is through preventing conversion of testosterone to dihydroxytestosterone (DHT). There is no evidence that Propecia causes prostate cancer and in fact its use is recommended in patients with strong family history of prostate cancer as a prevention for it. In studies performed at many university centers, it has been shown that finasteride 5mgs taken daily for 7 years, reduced the risk of prostate cancer by 25%.