Everything you need to know about
Prostate Radiotherapy
During the talk or at end send
QUESTIONS: 1 855-223-5455
QUESTIONS@PROSTATECANCERNETWORK.CA
Rob Rutledge, MD, Radiation Oncologist
Associate Professor, Dalhousie University
CEO, the Healing and Cancer Foundation
OVERVIEW OF TALK
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Complete prostate cancer care
Staging of curative prostate cancer
Treatment options by extent of cancer
Radiation after surgery
Role of hormone therapy and chemotherapy
Radiation for palliation
Questions and answers
COMPLETE PROSTATE CANCER CARE
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Information:
How to negotiate the medical system
Understanding prostate cancer and its treatment
Advice on complementary therapy
Medical care – Surgery, Radiotherapy…
Other medical system care: rehab, dietician, physio…
Psychosocial specialist for those with high distress
Empowering the person: body/ mind/ spirit
Body - Exercise, diet, weight, sleep, relaxation
Mind – Skills, stress-reduction, support
Spirit - awareness, nurturing what’s most important
PROSTATE CANCER ISSUES
• 95% will live for 10 years
• No agreed upon guidelines
• The urologist is the first person to outline
treatment options
• Lack of clinical trials
What is prostate cancer:
A layperson’s guide
WHAT IS PROSTATE CANCER?
• Normal prostate cell that has begun to grow in a
fast and uncontrolled way
• Requires dozens of changes to a normal prostate
cell
• Cancer cells will grow into normal tissue
• After more changes can get into lymph and blood
system to grow colonies at a distance
(metastasis)
HOW A TUMOUR GROWS
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A tumour is a collection of cancer cells
A tumour starts as one cancer cell
1 cell then 2 then 4 then 8 …..
Tumour growth if more cells are made
than die
• Tumour doubles in size over 1-3 years or
longer
• Tumour - 1 cm in size has a billion cells
HOW PROSTATE CANCERS
CAUSE PROBLEMS
• Problem in the prostate
– Narrow the tubing – urinate more often and
– Slowing of stream
• Spread to lymph nodes – uncommon
• Spread to other parts of body especially bones
• Affect whole body - fatigue
Factors determining
Treatment Options
• How advanced is the cancer (staging)
– Curable or not
• Factors in curable prostate cancer
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PSA – blood test
Rectal exam (T stage)
How aggressive is the cancer (Gleason Score)
How much cancer was seen on biopsy (# cores,
% cancer in each core)
• Fitness of the man
• What does the man want?
Prostate Specific Antigen - PSA
• A chemical produced by both normal
prostate cells and prostate cancer cells
• Inflammation / infection of the normal
prostate cells causes the PSA to increase
– Whether or not prostate cancer cells are
present
– Explains why the PSA can bounce up and down
• Excellent marker of cancer after diagnosis
– PSA should be undetectable after surgery
– PSA should be low after radiotherapy
PSA does not localize
cancer cells
• Prostate cancer cells
produce PSA no matter
where they are in the body
• A rapidly rising PSA and a
very high PSA likely means
there are cancer cells
beyond the prostate area
– Eg. PSA doubling time < 3
months or PSA >50
MAKING THE DIAGNOSIS
• Biopsy - take a piece of tumor
and look under microscope
• 8-12 cores of tissue – each
measuring 1cm by 0.1cm
• This is a tiny sampling of the
prostate gland
• May miss cancer completely
• May miss more aggressive
cancer
Gleason Score:
How aggressive is the cancer?
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Score is out of 10
Made up of two grades or patterns, each out of 5
First grade is the most common cancer seen
Second grade is the second most common cancer
Gleason score 6 or less is slow growing
– Example 3/5 plus 3/5
• Gleason score 8 or more is fast growing
• Gleason 7 is neither fast nor slow
T STAGE – felt on rectal exam
DRE:
T1=
No
lump
felt
STAGING OF POTENTIALLY CURABLE
PROSATE CANCER
• Rectal exam - T1C, T2, T3/4
• PSA - <10, 10-20, >20.
– How quickly it has increased
• Gleason score
• How much cancer is seen on the biopsy
– Number of cores involved, and percent cancer
• Optional tests for advanced disease:
– Bone scan, Cat scan
TREATMENT OPTIONS FOR
PROSTATE CANCER
Watch +/hormones
Curable
At Diagnosis
NonCurable
Watch +/treat for cure
later
TREAT NOW
for cure
Active Surveillance
• Watch, and if need be treat for cure later
• Means watching PSA and re-biopsy of prostate
every 1-2 years
• Go on to curative Rx if PSA jumps quickly,
urinary symptoms, or biopsy shows worsening
cancer
• Best for men with very slow growing cancers
whose life expectancy is less than 15 years
Low-risk prostate cancer
• Cancer is VERY LIKELY restricted to the prostate
gland
• Must have T2 (or less) and PSA <10 and Gleason
Score 6 (or less)
• Expect 80-95% chance of cure with treatment
• Active surveillance is good option for many
Low-risk prostate cancer
T1/T2 and PSA<10 and GS<7
Surgery
Therapy
Low risk
Surveillance
Seed
implant
External
Radiotherapy
Treatment for cure: operation
• Radical prostatectomy – removes the prostate and seminal
vesicles
• Has a specific side effects
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Related to major operation
Urinary incontinence 5-10%
Erectile dysfunction 30-70%
Bladder neck stricture 10%
• Is an excellent option in a situation where prostate cancer
cells are likely restricted to the prostate gland
• Removing the prostate gland provides much more
information about the aggressiveness and extent of cancer
• Radiotherapy can be used after surgery if it looks like cancer
is likely left behind in the surgical bed or if PSA begins to rise
in follow up
Treatment of cure:
Radioactive seeds in prostate
• Also called Low Dose Rate or Seed Brachytherapy
• Best for men with early disease when cancer cells
likely in prostate gland of just beyond capsule
• Very high cure rates similar to operation when
done by an experienced specialist
• “Simple” outpatient procedure
– General anaesthetic
– Rapid return to normal activity
– Men appear happy with this treatment
Seed Brachytherapy Advantages
• Technical:
– ultimate in dose escalation – 140 Gray
– rapid dose fall-off in surrounding tissues
(ultimate conformal)
– avoid external RT problems of target motion, setup variation and localization errors
Selection for Seed Brachytherapy
• Low risk cancer and early intermediate risk
– Shifting beyond low risk (GS 6, PSA<10, T1/2)
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Prostate less than 50-60cc in size
Reasonable urinary stream
Can undergo general anaesthesia
No preexisting rectal fistula or rectal surgery
– Need to have good rectal ultrasound pictures
• +/- previous pelvic radiotherapy
• +/- inflammatory bowel disease
• +/- prior TURP (ream out of prostate)
Brachytherapy planning
• All patients require dosimetric planning prior to
implantation
– 2-3 weeks before or intra operatively
• May not be able to get the needles into prostate
• May try again after 3-6 months of hormones
– Get 30% reduction in volume
Volume study geometry
Measuring needle penetration
Needle tip at C4
Side Effects of Seed Brachy
• Urinary
– Irritative and obstructive symptoms for 3-6 months
• Worse than with EBRT
– 1 in 10 needs catheter, temporarily
– ~85% will normalize within 1 year
– Incontinence rare
• Usually “urgency” incontinence
• Rectal
– Even mild toxicities are rare
– 1 in 1000 risk of breakdown
• Erectile function
– 80-85% will maintain erectile function afterwards
Treatment of Side Effects of Seed
Brachytherapy
• Pill for urinary flow (alpha blockers) prolonged
• Anti-inflammatories
• Watch out for urinary tract infections
• 15-20% incontinence if TURP (ream out) after
implant
• Erectile dysfunction (15-20%) can be treated with
pills
PSA bounce after Brachytherapy
• Rise in PSA > 0.2 ng/mL (later than 3 months) and
subsequent drop without intervention
• 1/3 of men will get this
– More likely if young, good erectile function, “hot” implant
• Usually within first 18 months
– Though not necessarily
• PSA can rise well above its lowest + 2 ng/mL
• No biopsy within 3 years!!
Treatment for cure:
External radiotherapy
• Technology has advanced in last few years to
allow very high dose of radiotherapy to gland
while minimizing dose to surrounding tissue
• Especially good for situations in which
prostate cancer cells beyond capsule of the
prostate but not spread elsewhere
CT SIMULATION
The Issue of Target Margin
around prostate
• The target is the prostate gland PLUS areas where
cancer cells may have spread
• Also have to account for set up error and motion of
the prostate gland
– Men need to have same degree of filling in bladder
– Bowel movement prior to simulation and treatment
daily
• Gold seeds can be inserted in prostate to localize
prostate during treatment
• The front rectum, bottom of bladder and urethra
DOSIMETRY
Prostate + Pelvic Lymph
Nodes
Simultaneous
Integrated
Boost
TREATMENT