Implications of the prostate cancer prevention trial: a decision analysis model of survival outcomes.
OBJECTIVE
To assess the estimated effect of finasteride prevention of prostate cancer on overall survival.


METHODS
Data for our decision tree model came from men in the two arms (finasteride or placebo) of the Prostate Cancer Prevention Trial (PCPT) and from clinically localized prostate cancer patients studied for long-term survival outcomes. Our model compared survival outcomes for men treated with finasteride or placebo. Prostate cancer rates were based on the 7-year period prevalence of prostate cancer detected in the PCPT; survival probabilities were abstracted from the long-term outcome studies. We assessed variability in the PCPT and long-term survival studies to test the variability of our model.


RESULTS
Survival advantages for a finasteride-treated (v those not treated with finasteride) population include gains of 1.7 months in 15-year cause-specific survival (assuming finasteride-altered Gleason scores and prostate cancer prevalence rates in the PCPT), of up to 3 months for cancers treated conservatively or surgically (assuming finasteride does not alter Gleason scores), and of 0.35 months (assuming the rate of cancers detected by for-cause biopsies in the PCPT), which increased to 1.7 months when assuming a 30% rate of biopsy-detected cancer in the PCPT placebo group. Model-variability analyses support several survival benefits associated with finasteride (eg, the uniform benefits assuming finasteride does not alter Gleason scores) but question certain others (eg, in 15-year recurrence-free survivals assuming finasteride does alter Gleason scores).


CONCLUSIONS
Finasteride can impart survival benefits according to our model, especially when we assume that finasteride does not alter Gleason scores.
Lotan
Yair
Y
Department of Urology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-9110, USA. Yair.Lotan@UTSouthwestern.edu
Cadeddu
Jeffrey A
JA
Lee
J Jack
JJ
Roehrborn
Claus G
CG
Lippman
Scott M
SM
D000368:Aged; D003663:Decision Trees; D004791:Enzyme Inhibitors / Q000627:therapeutic use*; D018120:Finasteride / Q000627:therapeutic use*; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011471:Prostatic Neoplasms / Q000453:epidemiology / Q000401:mortality / Q000517:prevention & control*; D016032:Randomized Controlled Trials as Topic; D016019:Survival Analysis; D016896:Treatment Outcome
D004791:Enzyme Inhibitors; D018120:Finasteride