© The Canadian Journal of Urology™; 21(Supplement 2); June 2014
18
Rosenberg ET AL.
There is significant controversy surrounding the
benefits of checking the prostate-specific antigen
(PSA).
26
Regardless of the PCP’s view on use of
this lab value, it must be remembered that the PSA
is prostate specific and not cancer specific. It was
shown by Roehrborn that a PSA value of 1.5 ng/mL,
in any age male, correlates to a minimal volume of 30
cc.
27
A review of the placebo arm of Medical Therapy
of Prostatic Symptoms (MTOPS) revealed that an
increase in size of the prostate is directly related to
increased risk of progression or worsening of LUTS
caused by the prostate.
28
The prostate volume assigned
to this risk was 31 cc. When used appropriately, the
PSA can assist the PCP and the patient in making an
educated decision about care as will be discussed in
the treatment section.
A bladder or voiding diary is a useful tool in the
evaluation of LUTS and should be considered especially
if there is concern of low urinary volumes. It may also
reveal the voiding habits that the patient has developed
andwhere theremay be opportunity to change behavior.
For example, some patients may have symptoms that
only occur during a certain time of the day or night.
Urinary production greater than 30% in the nighttime
is indicative of nocturnal polyuria. Urinary frequency
may be related to a time that the patient drinks copious
amounts of fluid or are unable to readily access a toilet.
Thus, the diarymay offer a clue to simple behaviors that
can be altered to minimize symptoms.
The post void residual, or PVR, is not necessary
in the initial evaluation of the uncomplicated patient.
If this value is needed, it can be measured by direct
catheterization or ultrasound scanning. An increased
PVRmay be a problem if it causes a significant decrease
in functional bladder capacity which can lead to
symptoms of urgency, frequency or nocturia.
29
While
there is no across-the-board consensus on a safe PVR,
for the PCP it is generally considered that a value of
less than 50 mL represents reasonably efficient voiding
and over 200mL is consistent with clinically significant
inadequate emptying.
12
In regards to the patient with
BPH, a large residual urine volume is consistent with
a significant risk of disease progression. One reason
to check the PVR is when the patient’s symptoms
are refractory to initial therapy. In this case the PCP
may consider checking for retention as a result of
the obstruction as the source for the poor response.
Ultrasonography (abdominal, renal, transrectal) and
intravenous urography are also not indicated in the
initial evaluation of the prostate related symptoms.
If needed, these can be useful in helping determine
the size of the prostate and the degree of bladder
emptying, and, in the case of urinary retention, the
presence of hydronephrosis (if suspected) and renal
impairment.
During the evaluation of BPH the PCP should be
aware of the risk factors for progression of the disease.
Crawford identified five factors that put the patient
at risk of progression. These include total prostate
volume ≥ 31 mL, PSA ≥ 1.6 ng/mL, Qmax (flow rate)
< 10.6 mL, PVR ≥ 39 mL or age ≥ 62.
28
It is understood
that not all of these values may be attained in the office
of the PCP; however, identification of riskmay assist in
eventual choice of therapy. Critical evaluation of these
factors allows a few practical and logical conclusions
for the PCP. As mentioned earlier, Roehrborn pointed
out that the PSA is a surrogate marker for prostate
size therefore the evaluation by a prostate ultrasound
is not necessary.
27
Flow and PVR, however, present
a problem in the PCP setting as these are not easily
acquiredwithout appropriate equipment. Having said
that, it can be assumed that there is a weakened flow as
the patient is presentingwith symptoms of obstruction.
Therefore, it is not likely that treatment choices would
be altered regardless of the flow rate. Likewise, one
would wonder if knowledge of the PVR would alter
initial therapy. Short of flagrant retention, the answer
is likely no. In the event that the patient with severe
retention filters through, what are the consequences?
If he responds to treatment, the PCP has helped
him. If he does not respond to therapy he would be
referred to a urologist for evaluation. Therefore, given
no other signs of an obstructive uropathy, the choice
of treatment does not hinge on the information of
flow rate or PVR.
29
Through this critical thinking we
propose that the clinician can assess risk by knowing
the PSA and its correlation to prostate size.
Red flags
The role of the PCP in the evaluation is not only to treat
the prostate, if appropriate, but also to identify other
possible causes of the LUTS. Those diagnoses that
cannot be addressed by the treating clinician should
be referred. Table 4 lists reasons for referral.
1
Treatment choices
Once BPH is determined to be the cause of the
obstructive symptoms there aremany options available
for the patient. The various choices depend on the
degree of bother, comorbid conditions, such as ED and
irritative symptoms, and risk of progression, as well as
success of prior treatment attempts. The PCP should
review these options with the patient in order to choose
whichever best fits their needs and expectations.
