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Proscar and aggressive prostate cancer
SB44 posted:
I'm very confused about the relationship between Proscar and prostate cancer and I am hoping someone can explain this. Back in 2003, there was a study showing that Proscar reduced the risk of contracting prostate cancer. At the same time, Dr. Peter Scardino published a study finding that, while Proscar did reduce the risk of prostate cancer, it also increased the risk of any prostate cancer being more aggressive. Dr. Scardino's findings seemed to be discredited by later findings that Proscar made aggressive cancer more detectable but did not increase the risk. Now the FDA is mandating a warning on Proscar and related drugs, stating that it can increase the risk of aggressive prostate cancer.

I'm very interested because I took Proscar for several years before being diagnosed with aggressive prostate cancer (Gleason 4+4) in 2008. At that time, I asked my surgeon about the role of Proscar and he said that the study finding it caused more aggressive cancer was an "artifact." Sounds like it now has more credence but, as I said, it's all very confusing.
az4peaks2 responded:
Hi HSB44, - I have an article that appears to give a balanced report of the discussions held before the FDA Advisory Committee vote, which was 18 to 0 not to include PCa reduction claims on the Proscar labeling. Just E-mail me for a copy by return E-mail. - too long to post here!

The fact is that the original study showed reductions of about 25% in PCa in the Proscar Group compared to the Placebo Group. It also showed that about that same 25% of those developing PCa had a higher Gleason Score PCa than those in the Placebo group.

I pointed out at the time, in a POST, that although the raw numbers were obviously smaller for those acquiring the disease, than for the total of all participants, they were characterized as a "small number" by the media, when in fact the PERCENTAGES were almost identical. These were findings of fact!

The "objective" raw results contained in ALL Medical Studies, are then subject to "conclusions" which are subjective interpretations attempting to explain the significance of the raw facts that were found, or acknowledgement that the cause of the unexpected findings are unknown. The latter was what the original Study stated.

Therefore the reason for this disturbing finding was addressed with Hypotheses by numerous experts, as to it's likely cause, with varying conclusions. One of these views, was that the shrinking of Prostate volume by the use of Proscar caused more high Grade Cancer to be found. This made NO "cause and effect" sense to me and I am happy to see that it didn't to Dr. Walsh of Johns Hopkins either.

On the other hand the contention that the shrinking of the Prostate induced by Proscar increases the possibility of finding any Cancer that exists in the smaller Prostate is logical and acceptable to me.

It appears clear that the known effect of Proscar on halving the PSA readings after 6 months of use, is likely more an affect on PSA than on the Cancer itself, which accounts for the widely accepted recommendation that such results be doubled for comparative purposes to non-Proscar treated results.

Note in the article that Avodart was included with Proscar in the 14 to 2 (2 abstained) vote to NOT allow claims of reduction of PCa risk to men having a previous Negative Biopsy - (aka) az4peaks
Fairwind replied to az4peaks2's response:
Pure anecdotal evidence..I was on Finasteride (Proscar) for 2 years before I was diagnosed with Gleason 9 PC on the third biopsy...It DID cut my PSA from 8 to 4, making my urologists job MUCH more difficult..

I was prescribed finasteride with a PSA of 8 after my second biopsy came back negative..I had no urinary symptoms and a normal DRE...

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