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What Are The
Side-Effects Of Your Treatment, Doctor? – A Discussion Of Urinary, Bowel
And Sexual Complications Of Primary Treatments Of Prostate Cancer.
(Oct. 2005)
When the question is
asked, “What are the unwanted complications that result from prostate
surgery, irradiation and brachytherapy?”, you might expect there are
straightforward answers. There are, of course, some overriding
generalities: surgery is associated with the most urinary incontinence and
sexual dysfunction; external beam radiotherapy with most bowel symptoms;
and brachytherapy with urinary irritation; and both radiation modalities
cause the least deterioration of sexual function, which, however, further
deteriorates as follow-up lengthens. But the “devil is in the details”.
More detailed analyses reveal complicating issues that blur simple
generalizations: e.g., what were the baseline functional capacities; how
does age affect the comparison of treatment complications; are tumor stage
and treatment techniques and comorbidities comparable in the groups being
compared; what evolution occurs in symptom severity over time, e.g. at 3
months, and at one, two and five years after treatment?
The most reliable
assessments emerge from the use of one or several validated
questionnaires, self administrated by each man and reported prospectively
prior to and sequentially during treatment. Many excellent single
institution, single modality studies are available that are very
appropriate for internal use, but don’t have the features that allow
informative inter-modality comparisons.
An exemplar study that
does incorporate these necessary features was reported by Talcott, D’Amico
et al. in JCO Nov. 2003: “Time Course and Predictors of Symptoms After
Primary Prostate Cancer”. This analysis focuses on urinary, bowel, and
sexual function over a two years period of follow-up and compares outcomes
from radical prostatectomy (with and without nerve-sparing), external beam
radiotherapy, and brachytherapy. The study was conducted by a consortium
of Boston teaching hospitals and involved 417 men (EBRT - 182, RP - 129,
BT - 80 patients) segregated into standard risk categories. The time
course for the extent of symptoms was graphed beginning with a baseline
assessment, with follow-up at 3, 12, and 24 months for each modality, and
separate outcome graphs displayed the data for sexual dysfunction (under
and over age 65), urinary incontinence, bowel problems, and obstructive/irritative
symptoms. The ordinate of each graph was a composite “mean score” for the
group under study, ranging from 0, best, to 100, worst. Each domain “mean
score” represented an summary integration of confounding factors (e.g age
stage), as was suggested above, and combined the several sub-functions
that are integral to global satisfaction in that domain. For example, in
the sexual domain the mean score integrated information relating to e.g.
firmness of erections, difficulty getting and keeping erections, and
frequency of ejaculation and orgasm. In the urinary domain the sub-issues
assessed were “the degree of urinary control and the frequency and
magnitude of leakaqe in men who had less than “complete control” and the
need for use of absorptive pads. Obstructive/irritative dysfunction
addressed “hesitancy, frequency of urination during the day, nocturia,
dysuria and urgency”. The final product was an integration of the
subcategories of a domain into a numerical “mean score”.
The graphs provide a very helpful
visual/global comparison among the three treatment modalities, and if the
extent of dysfunction assigned by these investigators seems higher than
often reported it is because their analysis has tried to capture the full
range of component elements that, taken as a group, affect a man’s sense
of satisfaction in a particular domain.
What are the findings? (Numbers are
approximate: +/- 1)
For this
article numerous reports were reviewed. Most reported follow-up on single
modality treatments or comparisons of two treatment types. In general, the
outcomes of these many studies fall within the range of results reported
by Talcott. However some additional informative points are contributed by
several of them.
A paper comparable in detail to the Talcott study was
presented by Potosky, JNCI Sept 2004: “Five-Year Outcomes After
Prostatectomy or Radiotherapy for Prostate Cancer: The Prostate Cancer
Outcome Study”. This is a comparison between 901 men treated with RP and
286 with EBRT. Their analysis of erectile dysfunction, similar to other
reports, finds that whereas at 2 years the dysfunction rate for RP is 82%
versus 50% for EBRT, at 5 years, while the impairment remains stable in
the RP group, dysfunction increased in the EBRT group to 63%, an
insignificant difference.
An important background point to keep in mind when
considering treatment outcome studies in general was highlighted by
Hoffman (CANCER Nov 2004) where the sexual function of treated men was
compared with matched normal controls. He established, not
surprisingly, that over five years sexual function declined significantly
among controls (whereas urinary function remained stable). This
information provides perspective for the interpretation of the functional
decrement in sexual function resulting from all treatment types.
Potosky confirmed that at five-year follow-up urinary
incontinence (defined as no control or frequent leakage) was worse after
RP, 14-16%, versus following EBRT. 4%.
Outcome evaluation for laparoscopic prostatectomy (LRP) was
compared to open RP (ORP) and BT by Soderdahl et al. (J Endourol. 2005
Apr). Validated, sequentially self-administered tools were returned by 452
men at 0,3,6,9 and 12 months. Results, reported as % return to baseline
function”: 1) urinary function - ORP, 38%; LRP, 46%, BT, 75%; 2) sexual
function - ORP, 19%: LRP, 19%; BT, 63%.
Studies that compare BT and EBRT establish that greater
dysfunction results from EBRT. The addition of EBRT to BT leads to more
sexual dysfunction than BT alone. Merrick (Oncology, Vol 17, Number 1)
found, as have others, that with radiotherapy men’s sexual dysfunction
increased over 5 years to 50%. Potency was preserved at 5 years in
57% of men undergoing BT as monotherapy but with added EBRT
preservation dropped to 39%. Encouragingly, he found that Viagra
helped the majority of affected men whose pretreatment function had been
satisfactory.
Bottom Line: All forms of
primary therapy for prostate cancer are associated with varying, but
important, degrees of deterioration in urinary, bowel and sexual function,
and these complications change over time. These issues need to be
factually addressed with men prior to treatment. An excellent validated
study which could serve as a desk reference for this discussion is the JCO
Talcott report.
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