Radiology, Vol 178, 197-199, Copyright © 1991 by Radiological Society of North America
Nonpalpable cancer of the prostate: assessment with transrectal US
F Lee Jr, JP Bronson, F Lee, ST Torp-Pedersen, DB Siders, JR Thornbury and TA McHugh
Department of Diagnostic Radiology, University of Rochester Medical Center, NY 14642.
Palpable cancer of the prostate is widely believed to be clinically
significant. The authors compared the clinical significance of palpable
prostate cancer with nonpalpable prostate cancer discovered with
transrectal ultrasound (US). A strong association between lesion volume
measured with preoperative transrectal US and volumetric measurements in 60
radical prostatectomy specimens permitted the use of tumor size measured
with transrectal US as a reasonable estimation of gross tumor volume. In a
subsequent clinical series, 147 biopsy-proved cancers were grouped
according to size measured at US, the findings at digital rectal
examination (DRE), and the Gleason score. For the 147 patients with known
prostate cancer, a statistically significant difference between Gleason
scores of palpable and nonpalpable cancers could not be demonstrated when
the size of the tumor and its location within the prostate were held
constant. Assuming that the Gleason score is a reliable indication of
malignant potential and clinical significance, the authors conclude that
nonpalpable prostatic cancer detected with transrectal US alone may be just
as clinically significant as prostatic cancer discovered with DRE.
