Radiology, Vol 198, 439-442, Copyright © 1996 by Radiological Society of North America
Systematic biopsies: do they add prognostic information in men with clinically localized prostate cancer treated with radiation therapy alone?
WR Lee, AL Hanlon and GE Hanks
Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA 19111, USA.
PURPOSE: To determine whether systematic biopsy can help predict treatment
outcome in men with clinically localized prostate cancer treated with
external-beam radiation therapy alone. MATERIALS AND METHODS: Two hundred
twenty-four men with clinically localized prostate cancer underwent
ultrasound-guided systematic biopsies before undergoing external-beam
radiation therapy. Median follow-up was 25 (range, 4-80) months. Treatment
failure after irradiation was defined as a prostate-specific antigen (PSA)
level greater than 1.5 ng/mL and rising. RESULTS: Univariate analysis
demonstrated that the percentage of biopsy specimens involved by cancer was
predictive of relapse-free survival. Patients in whom more than 50% of
biopsy specimens were positive had significantly lower relapse-free
survival rates at 36 months than patients with 50% or fewer positive biopsy
specimens. After stratifying patients according to pretreatment PSA level,
however, the percentage of positive biopsy specimens was no longer
prognostic. Multivariate analysis demonstrated that pretreatment PSA level
was the only variable that enabled prediction of relapse-free survival.
CONCLUSION: Systematic biopsy added little further prognostic information
beyond that provided by pretreatment PSA level. A larger series with longer
follow-up is necessary to verify these results.
