The first step in managing Mr. D’s case is to clarify his treatment
options and
their potential risks and benefits. He uses the phrase “watchful waiting”
which actually connotes a palliative approach to prostate cancer, where
the
intention is to offer symptomatic relief if and when cancer progresses.
Given
the often indolent course of prostate cancer, this approach makes most
sense
for men with limited life expectancies due to advanced age or
comorbidities.
However, Mr. D is young and fairly healthy, so watchful waiting is not
necessarily an appropriate option. Even though his cancer is moderately
differentiated, population-based survival data suggest that, without
treatment, he has over a 20% chance of dying from prostate cancer in 20
years (1). At the same time, he might be one of the estimated 23% to 42%
of
men with PSA-detected cancers who never have clinical problems with
prostate cancer (2)—other than those associated with diagnosis and
treatment.
Many men with an early-stage cancer who share Mr. D’s concerns about
treatment complications--but are uncomfortable with foregoing treatment--
have opted for androgen deprivation therapy (ADT)(3). However, ADT is not
really an acceptable compromise for these men because it also has many
potential complications, does not cure cancer, and is expensive. So, are
there
any other options for Mr. D? He could consider active surveillance (AS).
This
strategy, which is recommended for men with less than a 10- to 15-year
life
expectancy, PSA ≤ 10 ng/mL, low tumor burden, and no worse than a
moderately differentiated cancer, involves serial PSA testing, digital
rectal
examinations, and prostate biopsies (4). Engaging in AS means that a
future
decision for curative treatment would be based on evidence that cancer is
progressing—rising PSA, changing DRE, or worsening Gleason score. This
may strike a reasonable balance for men who want to avoid complications
from unnecessary treatment but do not want to ignore their cancer. Recent
observational data from a small multi-institutional cohort study found
that
75% of subjects remained on active surveillance after a median follow-up
of
29 months--and only one developed skeletal metastases (5). So while a
cancer could progress under active surveillance and become incurable, the
chance of this seems small.
Admittedly, Mr. D may not quite fit the guideline indications for AS;
the foci
of atypia and high-grade intraepithelial neoplasia suggest that his tumor
volume could have been underestimated and he has a long life expectancy.
Whether or not he opts for active surveillance, Mr. D should be fully
educated
about the natural history of prostate cancer and the potential risks and
benefits associated with various treatment options. He should also
understand that radiotherapies (external beam and brachytherapy), unlike
radical prostatectomy, have never been evaluated in controlled trials of
men
with early-stage cancer. Thus, there is no evidence-based consensus on
the
optimal treatment. Given this uncertainty about treatment selection and
the
risks for overdiagnosis, the most important recommendation for Mr. D is
that
he be involved in an informed/shared decision-making process regarding his
treatment.
References
1. Albertsen PC, Hanley JA, Fine J. 20-year outcomes following
conservative
management of clinically localized prostate cancer. Jama. May 4
2005;293(17):2095-2101.
2. Draisma G, Etzioni R, Tsodikov A, et al. Lead time and overdiagnosis in
prostate-specific antigen screening: importance of methods and context. J
Natl Cancer Inst. Mar 18 2009;101(6):374-383.
3. Cooperberg MR, Moul JW, Carroll PR. The changing face of prostate
cancer. J Clin Oncol. Nov 10 2005;23(32):8146-8151.
4. Thompson I, Thrasher JB, Aus G, et al. Guideline for the management of
clinically localized prostate cancer: 2007 update. J Urol. Jun
2007;177(6):2106-2131.
5. Eggener SE, Mueller A, Berglund RK, et al. A multi-institutional
evaluation
of active surveillance for low risk prostate cancer. J Urol. Apr
2009;181(4):1635-1641; discussion 1641.