Encyclopedia of Health and Medicine

328 The Reproductive System
Prostate cancer is the most frequently diagnosed
cancer among men in the United States and
is primarily found in men over age 60. Though
prostate cancer may take an aggressive path with
widespread METASTASIS that leads to premature
death, prostate cancer more often than not is a
slow-growing cancer and runs a course that doctors
can control through various treatments. Far
more men die with prostate cancer than from
prostate cancer. With early detection and treatment,
prostate cancer may be curable.
The symptoms of prostate cancer are often difficult
to distinguish from the symptoms of noncancerous
conditions that affect the prostate
gland, particularly BENIGN PROSTATIC HYPERPLASIA
(BPH). All men eventually develop some degree of
BPH as they grow older, enlargement of the
prostate gland begins to occur as a natural dimension
of aging. However, BPH is not and does not
become prostate cancer, though a man may have
both conditions concurrently.
Symptoms and Diagnostic Path
Early to moderately advanced prostate cancer may
cause no symptoms, with diagnosis resulting from
further investigation of an abnormally high
PROSTATE-SPECIFIC ANTIGEN (PSA) BLOOD level or
abnormal findings during DIGITAL RECTAL EXAMINA-
TION (DRE) performed during a ROUTINE MEDICAL
EXAMINATION. When symptoms are present they
may include
• frequent URINATION, particularly at night (NOC-
TURIA)
• incomplete emptying of the bladder with urination,
sometimes resulting in URINARY URGENCY,
URINARY FREQUENCY, and URINARY TRACT INFECTION
(UTI)
• reduced urinary flow, urinary hesitation (difficulty
starting the flow of urine), and dribbling
(difficulty stopping the flow of URINE)
• blood in the urine (HEMATURIA) or SEMEN
(hematospermia)
• sensation of heaviness or fullness in the lower
abdomen (pelvic area)
• low BACK PAIN or rectal pressure
The diagnostic path may include DRE to palpate
the prostate gland, blood tests to measure
PSA levels and detect the presence of other TUMOR
MARKERS, urinalysis, transrectal ULTRASOUND
(TRUS), and biopsy (multiple tissue samples) of
the prostate gland.
STAGING AND GRADING OF CANCER are critical for
identifying and selecting the most appropriate
treatment options. Several systems exist for cancer
staging and grading. Because prostate cancer cells
typically invade different areas of the prostate
gland at varying levels of what pathologists call
architectural disorder—the extent to which the
cell structure deviates from normal—conventional
staging and grading methods often cannot accurately
classify the prostate cancer overall. Some
areas of invasion may be fairly advanced and others
minimally involved. The Gleason system and
the Jewett system are methods unique to prostate
cancer and the ones most doctors use to guide
treatment decisions. In addition, conventional
staging methods provide further classification.
Gleason pattern and score The Gleason system
allows the pathologist to select the pattern (sometimes
called grade) of the two most predominant
architectures (primary and secondary) among the
biopsy samples and combine them into a score
that represents the character of the prostate cancer
overall. There are five patterns and nine scores
possible within the Gleason system. The lower the
Gleason score (also called the Gleason sum), the
more likely the cancer is confined and will
respond to treatment. However, the patterns that
establish the score are also important. For example,
a prostate cancer that has a Gleason score of 7
coming from 3 + 4 has a more positive prognosis
than one with a Gleason score of 7 coming from a
4 + 3 because the first number indicates the primary
pattern and pattern 3 is less aggressive than
pattern 4. It is important to know both patterns as
well as the score.
Jewett staging system The Jewett system, also
called the Jewett-Whitmore system, assigns four
alphabetic values to the extent of cancer metastasis,
with numeric subvalues for more precise classification.
Conventional staging Some doctors additionally
use conventional staging and grading systems