|Detection & Screening
The purpose of screening for cancer is to
detect the cancer at its earliest stages, before any symptoms
Some men, however, will experience symptoms that
might indicate the presence of prostate cancer. Because these symptoms can
also indicate the presence of other diseases or disorders (such
these men will undergo a more thorough work-up. Typically, men
whose prostate cancer is detected through screening are found to
have very early-stage disease that can be treated most
Screening for prostate cancer can be
performed quickly and easily in a physician’s office using two
tests: the PSA (prostate-specific antigen) blood test, and the
digital rectal exam (DRE).
The PSA Blood Test
PSA is a protein produced by the prostate and released
in very small amounts into the bloodstream. When there’s a
problem with the prostate, such as when prostate cancer develops
and grows, more and more PSA is released, until it reaches a
level where it can be easily detected in the blood.
During a PSA test, a small amount of blood
is drawn from the arm, and the level of PSA is measured. PSA
levels under 4 ng/mL are usually considered "normal,"
results over 10 ng/mL are usually considered "high,"
and results between 4 and 10 ng/mL are usually considered
However, PSA can also be elevated if other
prostate problems are present, such as BPH
and some men with prostate cancer have "low" levels of
PSA. This is why both the PSA and DRE are used to detect the
presence of disease.
The Digital Rectal Exam
During a DRE, the physician inserts a gloved, lubricated finger
into the rectum and examines the prostate for any irregularities
in size, shape, and texture. Often, the DRE can be used by
urologists to help distinguish between prostate cancer and
non-cancerous conditions such as BPH.
Should I Be Screened?
The American Cancer Society recommends that both the PSA and DRE
should be offered annually, beginning at age 50, to men who have
at least a 10-year life expectancy. Men at high risk, such as
African American men and men with a strong family history of one
or more first-degree
relatives diagnosed at an early age, should begin testing at
However, there is no unanimous opinion in
the medical community regarding the benefits of prostate cancer
screening. Those who advocate regular screening believe that
finding and treating prostate cancer early offers men more
treatment options with potentially fewer side effects. Those who
recommend against regular screening note that because most
prostate cancers grow very slowly, the side effects of treatment
would likely outweigh any benefit that might be derived from
detecting the cancer at a stage when it is unlikely to cause
Because a decision of whether to be
screened for prostate cancer is a personal decision, it's
important that each man talk with his doctor about whether
prostate cancer screening is right for him.
Prostate Cancer Symptoms
For an extensive overview of what can go
wrong with the prostate, read Chapter
2 "Little Gland, Big Trouble" from the book Dr.
Patrick Walsh's Guide to Surviving Prostate Cancer.
If the cancer is caught at its earliest
stages, most men will not experience any symptoms. Some
men, however, will experience symptoms that might indicate the
presence of prostate cancer, including:
- A need to urinate frequently,
especially at night;
- Difficulty starting urination or
holding back urine;
- Weak or interrupted flow of urine;
- Painful or burning urination;
- Difficulty in having an erection;
- Painful ejaculation;
- Blood in urine or semen; or
- Frequent pain or stiffness in the lower
back, hips, or upper thighs.
Because these symptoms can also indicate
the presence of other diseases or disorders, such as BPH or
men who experience any of these symptoms will undergo a thorough
work-up to determine the underlying cause of the symptoms.
Although the DRE and PSA tests cannot
diagnose prostate cancer, they can signal the need for a biopsy
to examine the prostate cells and determine whether they are
cancerous. In some men, changes in urinary or sexual function
lead to a full evaluation by the doctor, and, if prostate cancer
is suspected, a biopsy will be performed.
During a biopsy, needles are inserted into the prostate to take
small samples of tissue, often under the guidance of ultrasound
imaging. The biopsy procedure may cause some discomfort or pain,
but the procedure is short, and can usually be performed without
an overnight hospital stay.
Gleason Grading and Gleason Scores
Under normal conditions, prostate cells, just like all other
cells in the body, are constantly reproducing and dying, and
each new prostate cell has the same shape and appearance as all
of the other prostate cells. But cancer cells look different,
and the degree to which they look different from normal cells is
what determines the cancer grade. "Low-grade" tumor
cells tend to look very similar to normal cells, whereas
"high-grade" tumor cells have mutated so much that
they often barely resemble the normal cells.
The Gleason grading system accounts for
the five distinct patterns that prostate tumor cells tend to go
through as they change from normal cells. The scale runs from 1
to 5, where 1 represents cells that are very nearly normal, and
5 represents cells that don’t look much like prostate cells at
After examining the cells under a
microscope, the pathologist looking at the biopsy sample assigns
one Gleason grade to the most common pattern, and a second
Gleason grade to the next most common pattern. The two grades
are added, and the Gleason score, or sum, is determined.
Generally speaking, the Gleason score
tends to predict the aggressiveness of the disease and how it
will behave. The higher the Gleason score, the less the cells
behave like normal cells, and the more aggressive the tumor
tends to be.
Staging the Disease
Staging determines the extent of prostate cancer.
Localized prostate cancer means that the cancer is confined
within the prostate. Locally advanced prostate cancer means that
most of the cancer is confined within the prostate, but some has
started to escape to the immediate surrounding tissues. In
metastatic disease, the prostate cancer is growing outside the
prostate and its immediate environs, possibly to more distant
A number of tests can be used to help
determine the stage of disease. For example, cancers growing
outside of the prostate can often be detected through
traditional imaging studies, such as CT scans, MRIs, or x-rays,
or through more specialized imaging tests such as bone scans.
Note that because these tests cannot detect very small groups of
cancer cells, results of these tests cannot be used alone to
determine the stage of the disease, to guide treatment options,
or to predict outcomes.
Metastatic disease can also be detected
through imaging studies, and often can be detected in the lymph
nodes. Cancers that spread to more distant organs tend to travel
through the lymph system, a circulatory system similar to the
blood stream that carries cells important in fighting infection
and disease. During a biopsy, or, more often, during surgery,
lymph nodes will be removed and examined for the presence of
Knowing the stage of disease can help to
determine how aggressively the disease needs to be treated, and
how likely it is to be eradicated by the available treatment
There is no "one size fits all"
treatment for prostate cancer, so each man must learn as much as
he can about various treatment options and, in conjunction with
his physicians, make his own decision about what is best for
For most men, the decision will rest on a
combination of clinical and psychological factors. Men diagnosed
with localized prostate cancer today will likely live for many
years, so any decision that is made now will likely reverberate
for a long time. Careful consideration of the different options
is an important first step in deciding on the best treatment
Consultation with all three types of
prostate cancer specialists—a urologist, a radiation
oncologist and a medical oncologist—will offer the most
comprehensive assessment of the available treatments and
Click on the following for more
information about particular treatment options for prostate