Prostate cancer diagnosis among men with isolated high-grade intraepithelial
neoplasia enrolled onto a 3-year prospective phase III clinical trial of oral
toremifene.
Author(s): Taneja SS(1), Morton R, Barnette G, Sieber P, Hancock ML, Steiner M.
Affiliation(s): Author information:
(1)Division of Urologic Oncology, 150 East 32nd St, Ste 200, New York, NY 10016,
USA. samir.taneja@nyumc.org
Publication date & source: 2013, J Clin Oncol. , 31(5):523-9
PURPOSE: Prostate cancer (PCa) prevention remains an appealing strategy for the
reduction of overtreatment and secondary adverse effects. We evaluated the
efficacy of toremifene citrate 20 mg in PCa prevention among men with isolated
high-grade prostatic intraepithelial neoplasia (HGPIN) on biopsy.
PATIENTS AND METHODS: One thousand five hundred ninety men with HGPIN, or HGPIN
and atypia, and no PCa on prostate biopsy were randomly assigned 1:1 to receive
toremifene citrate 20 mg or placebo in a 3-year phase III, double-blind,
multicenter trial. Men underwent annual biopsy until cancer detection or study
end. Efficacy analysis was performed in 1,467 men who underwent at least one
on-study biopsy. Baseline risk factors were evaluated to determine influence on
cancer detection.
RESULTS: Cancer was detected in 34.7% and 32.3% of men in the placebo and
treatment groups, respectively, with no observed difference (P = .39, log-rank
test) in PCa-free survival. The 3-year Kaplan-Meier PCa-free survival estimate
was 54.9% (99% CI, 43.3% to 66.5%) in the placebo group and 59.5% (99% CI, 48.1%
to 70.9%) in the treatment group. Exploration of baseline risk factors
demonstrated no subset in which a risk reduction was observed. In the placebo
group, 17.9%, 12.9%, and 13.6% of men at risk at the beginning of years 1, 2, and
3, respectively, were diagnosed with PCa.
CONCLUSION: Although toremifene 20 mg did not lower the PCa detection rate, men
with isolated HGPIN have a high likelihood of eventual PCa diagnosis,
demonstrating they are ideal candidates for inclusion in chemoprevention trials
and require surveillance by periodic prostate biopsy.
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