©TheCanadian Journal ofUrology™: International Supplement, April 2014
Addresscorrespondence toDr.BobbyShayegan,McMaster
Institute of Urology, 50 Charlton Ave E, Room G339A,
Hamilton,ONL8N 4A6Canada
Intermittent androgendeprivation therapy
for prostate cancer: translating randomized
controlled trials into clinical practice
ShawnDason,MD, ChristopherBrianAllard,MD, JingGennieWang,MD(c),
JenHoogenes,MS, BobbyShayegan,MD
DivisionofUrology,Department of Surgery,McMasterUniversity,Hamilton,Ontario, Canada
DASONS,ALLARDCB,WANG JG,HOOGENES J,
SHAYEGAN B. Intermittent androgen deprivation
therapy for prostate cancer: translating randomized
controlled trials intoclinicalpractice.
Can JUrol
2014;
21(Suppl 1):28-36.
Introduction:
Intermittentandrogendeprivationtherapy
(IADT) for prostate cancer involves cycles of androgen
deprivation therapy (ADT)with a period between cycles
where testosterone isallowed to riseabovecastrate levels.
Anumber of recent randomized controlled trials (RCTs)
have compared survival andhealth-relatedquality-of-life
(HRQOL)between IADTandcontinuousADT (CADT).
This review seeks to critically analyze these published
trials for their relevance to clinical practice.
Materialsandmethods:
Published trialswereretrieved
fromasystematicsearchofMEDLINE,EMBASEand the
CochraneCentralRegister ofControlledTrialsdatabases
using relevant keywords. Recent systematic reviews
publishedon this topicwerehand-searched foradditional
applicable references. The evidencewas then synthesized
for this review.
Results:
Anumber of phase III trials have been recently
published. IADT was found to be non-inferior in the
primary setting for non-metastatic prostate cancer as
well as in treatment of biochemical recurrence following
radiotherapy. However, these studies overrepresented
low risk patients inwhom considerationmay be given to
deferredADT rather than early treatmentwith IADT. In
themetastaticprostatecancersetting, IADTwasnot found
to be non-inferior to CADT. In most trials, castration
related symptoms improved with IADT and overall
HRQOL resultsweremixed. Little data are available on
the effect of IADT on long term complications ofADT.
Conclusions:
IADTremainsa treatmentwithuncertain
outcomes in metastatic prostate cancer and uncertain
valueoverdeferringADTentirely inotherprostatecancer
clinical states.
KeyWords:
health-related quality-of-life, cancer
of the prostate, androgen deprivation therapy,
hormonal therapy
adoptedsince thediscoveryofADT, thisapproachhas
been limited by adverse cardiovascular effects.
2
The
discovery of luteinizinghormone releasinghormone
(LHRH) agonistsmadeavailableamedical option for
HPG-axis suppression without the thromboembolic
effects of estrogens.
3
Today, medical ADT is usually
favoredoverorchiectomybecauseof thepotential for
intermittent androgen deprivation, lack of surgical
complications, andpossiblepsychological benefits of
testicular preservation.
Androgendeprivationtherapymaybeadministered
onacontinuousor intermittentschedule. Continuous
androgen deprivation therapy (CADT) suppresses
Introduction
Androgen deprivation therapy (ADT) has been a
mainstay in the treatmentofadvancedprostatecancer
since its use was reported by Huggins and Hodges
in 1941.
1
Androgen deprivation was classically
accomplished surgically with bilateral orchiectomy.
Although estrogen-mediated suppression of the
hypothalamic-pituitary-gonadal (HPG)-axishasbeen
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