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UROLOGICAL
ONCOLOGY
Analysis
of T1c prostate cancers treated at very low prostate-specific antigen
levels
Stephenson AJ, Jones JS, Hernandez AV, Ciezki JP, Gong MC, Klein EA
Section of Urologic Oncology, Glickman Urological and Kidney Institute,
Department of Quantitative Health Sciences, Cleveland Clinic Foundation,
Cleveland, Ohio, USA
Eur Urol. 2009; 55: 610-6
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Background:
The Prostate Cancer Prevention Trial (PCPT) has challenged the validity
of recommended prostate-specific antigen (PSA) thresholds for prostate
biopsy (> 2.5 ng/ml) given the 17% prostate cancer (pCA) detection
rate at PSA of 1.1-2.0. The outcome of patients treated at PSA <
or = 2.5 is poorly defined, and advantages associated with such an
early diagnosis are uncertain.
Objective: Compare the outcome of patients with T1c pCA with pretreatment
PSA < or = 2.5 and 2.6-4.0.
Design, Setting, And Participants: Since 1998, 351 patients with clinical
stage T1c and PSA < or = 4.0 have been treated at our institution;
84 (24%) of those patients had PSA < or = 2.5. Clinical information
was obtained from a prospective database. Treatment was radical prostatectomy
(RP), brachytherapy, and external-beam radiotherapy (EBRT) in 261
(74%), 67 (19%), and 23 (7%) patients, respectively.
Intervention: Definitive therapy for clinically localized pCA.
Measurements: Progression-free probability and pathologic end points.
Results and Limitations: No significant differences between the groups
were observed in terms of biopsy (18% vs 22%) or specimen Gleason
score 7-8 (44% vs 56%), non-organ-confined cancer (11% vs 13%), indolent
cancer (34% vs 24%), or 5-yr progression-free probability (89% vs
93%; p>0.1 for all). More biologically unimportant cancers (defined
as pathologically organ-confined and Gleason < or = 6) were identified
among patients with PSA < or = 2.5 (55% vs 41%, p=0.050), and indolent
cancers were three times more frequent than non-organ-confined cancers
among these patients (p=0.003).
Conclusions: The pathologic features and outcome of patients treated
at low PSA levels are favorable and similar for patients with PSA
< or = 2.5 versus 2.6-4.0. However, > 50% of the former have
potentially biologically unimportant cancer. We failed to identify
a therapeutic benefit to the diagnosis of cancers below accepted PSA
thresholds for biopsy.
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Editorial
Comment
The debate of lowering the threshold for biopsy in patients with a
low PSA is still active and gets some support from this paper. The
authors compare the results from two cohorts of patients with low
PSA, namely < 2.5 ng/ml and 2.5-4 ng/ml. They did not find any
significant differences between these groups but further data in this
paper are of interest. Taken together both groups, 21% of these patients
had biopsy Gleason sum scores 7 or 8, whereas 53% had specimen Gleason
scores 7-8, again suggesting undergrading in biopsies. 12% had non-organ
confined cancers and 12 % had positive surgical margins.
Altogether these and other data (e.g. from the PCPT trial) suggest
that the threshold for performing biopsies is rather low and should
include more factors than PSA alone.
Dr.
Andreas Bohle
Professor of Urology
HELIOS Agnes Karll Hospital
Bad Schwartau, Germany
E-mail: boehle@urologie-bad-schwartau.de
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