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Sadi MV et al.
722 Rev Assoc Med Bras 2017; 63(8):722-725
REVIEW ARTICLE
PSA screening for prostate cancer
Marcus V. Sadi 1*
1Adjunct Professor, Habilitation degree (Livre-docência) in Urology, Escola Paulista de Medicina da Universidade Federal de São Paulo (EPM-Unifesp). Head of the Urologic Oncology Sector at EPM-Unifesp. Graduate
degrees from Harvard Medical School and The Johns Hopkins School of Medicine. Member of Academia de Medicina de São Paulo, São Paulo, SP, Brazil
Summary
Study conducted at Urologic
Oncology Sector, Division of Urology,
Escola Paulista de Medicina da
Universidade de São Paulo (EPM-Unifesp),
São Paulo, SP, Brazil
Article received: May 2017
Accepted for publication: July 2017
*Correspondence:
Address: Av. Indianópolis, 908
São Paulo, SP – Brazil
Postal code: 04062-001
Screening of prostate cancer with prostate-specific antigen (PSA) is a highly
controversial issue. One part of the controversy is due to the confusion between
population screening and early diagnosis, another derives from problems related
to the quality of existing screening studies, the results of radical curative treatment
for low grade tumors and the complications resulting from treatments that affect
the patient’s quality of life. Our review aimed to critically analyze the current
recommendations for PSA testing, based on new data provided by the re-evaluation
of the ongoing studies and the updated USPSTF recommendation statement,
and to propose a more rational and selective use of PSA compared with baseline
values obtained at an approximate age of 40 to 50 years.
Keywords: PSA, prostate cancer, screening, prostate.
In Brazil, prostate cancer is the most frequent malignant
tumor in men, except for non-melanoma skin tumors.
More than 62,000 new cases and almost 14,000 deaths
are estimated for 2016/2017.1
Autopsy studies show that up to 60% of men over the
age of 70 may have prostate cancer. However, only a small
proportion of these tumors are clinically significant. These
tumors of indolent clinical behavior are known as latent
cancer, and their diagnosis should be avoided.2
Prostate cancer is classified based on the Gleason grad-
ing system, which provides scores for each tumor. Due to
the common heterogeneity found in these tumors, two
scores are stipulated for the predominant pathological
aspect of each case, numbered from 1 to 5. Therefore, the
final grades vary from 2 (1+1) to 10 (5+5). The higher the
score, the more undifferentiated is the tumor, the greater
the chance of metastatic disease, and the worse the patient’s
prognosis. An international consensus of pathologists in
2004 decided to abolish the use of scores 1 and 2 and
denote all low grade tumors as 3. Thus, the lowest cur-
rently possible Gleason score is 6 (3+3), representing tu-
mors of low histological aggressiveness; Gleason 7 (3+4
or 4+3) of intermediate aggressiveness and Gleason 8-9-10,
representing aggressive tumors with a high level of ana-
plasia. Recently, after an analysis of more than 16,000
patients undergoing radical prostatectomy and monitored
for several years, the International Society of Urological
Pathology (ISUP) recommended a new tumor classification,
as follows: GS 6 (3+3 = ISUP 1) and 7 (3+4 = ISUP 2)
representing tumors of lower aggressiveness, GS 7 (4+3 =
ISUP 3) and GS 8 (4+4 = ISUP 4), representing tumors of
intermediate risk, and GS 9 and 10 (ISUP 5), representing
aggressive tumors.3 Usually, the tumors found in the screen-
ing programs are ISUP 1 or 2.4
Over the past 20 years, since the clinical introduction
of prostate-specific antigen (PSA), the incidence of meta-
static prostate cancer and mortality from prostate cancer
has significantly decreased. Although there is no absolute
proof that the use of PSA was responsible for this decrease,
in the 1980s, localized prostate tumors represented less
than 60% of the cases and in recent years less than 5% of
patients have initial metastatic presentation. Five-year
cancer-specific survival increased from 69% in the 1970s
to more than 95% nowadays, coinciding with the wide-
spread use of this examination. 5
An ideal screening program should focus on dis-
eases with high clinical impact on public health; screen
the population with a long life expectancy; be able to
identify asymptomatic disease at a treatable stage during
its natural course; have a high-accuracy, non-invasive,
easy-to-apply, low-cost diagnostic tests that does not
detect latent tumors; have a treatment capable of modi-
fying the natural history of the disease, reducing mortal-
ity without worsening quality of life.