I'm curious about Finasteride, as a preventive measure for prostate cancer. I've written to Dr Catalona a while ago regarding this subject and he was against using Finastride as a prevention measure. He had written a Quest article about it (pasted below), this was written in 2008 and I believe a second study looked at the results and declard Finasteride *does not* increase the chance of aggressive PCa.
What is your opinion regarding Finasteride?
Any treatment that reduces androgen effects is considered “hormonal therapy,” because many, but never all, prostate cancer cells cease to proliferate or die when androgenic stimulation is substantially reduced.
A central question, therefore, is whether taking finasteride is true “chemoprevention” or whether it is merely a weak form of early hormonal therapy that masks and delays the detection of prostate cancer.
An alternative hypothesis to finasteride providing true chemoprevention of prostate cancer that is consistent with the available data is as follows:
(1) Finasteride cannot prevent prostate cancer; it merely delays progression of low-grade prostate cancer;
(2) Finasteride suppresses the growth of normal prostate tissue, benign prostate hyperplasia tissue, and low-grade prostate cancer cells, but cannot control aggressive, high-grade cancer, and eventually, if given time, high-grade cancer will emerge.
In a clinical trial with longer follow-up (15 to 20 years), it is possible that “masking” high-grade prostate cancer with finasteride until it is too late for cure might outweigh any benefits from delaying or preventing the detection of lower-grade cancers.
If a prostate cancer chemoprevention study has a limited time span of 7 years, a delay in cancer detection would produce the appearance of a decrease in cancer incidence. However, with longer follow-up, this apparent benefit would substantially diminish or disappear.
This situation was, in fact, the case in the Prostate Cancer Prevention Trial among patients who had a biopsy “ for cause” or after an interim procedure, such as a transurethral resection of the prostate for presumed benign enlargement of the prostate. Among the men who were biopsied seven years after randomization (They biopsied 7.1 % of men in the placebo arm and 7.0% in the finasteride arm.), a nearly equal number of cancers (124) in the placebo arm and in the finasteride arm (122) were diagnosed; however, 64 (52%) of the cancers in the finasteride arm were high-grade as compared with only 38 (31%) in the placebo arm.
Until further information is available, I recommend only the FDA-approved use of finasteride in men with severe symptoms from benign prostatic enlargement that have not responded to alpha-blocker therapy (such as Flomax) and want to delay surgical intervention for relief of urinary obstruction.
I warn them that finasteride might mask high-grade prostate cancer.
I recommend a prostate biopsy to rule out cancer before starting finasteride, and I recommend a repeat biopsy if the PSA rises while the patient is on finasteride treatment after I have ruled out other possible causes for the PSA increase.