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Proton Radiation - Increased Recurrence Rate Will
seed implants improve my likelihood of being cured?YES! Our cure rates with seed implants are 20 to
40% better than the best results ever published with proton beam therapy. Seed implants have the unique advantage of having
the radiation placed directly into the cancer. The radiation is concentrated where it needs to be, without the unnecessary
high dose radiation of areas outside the prostate, as occurs with proton therapy. (see chart below)

A recent study from the largest proton center in the country at Loma Linda, California reported that for 1,225
men with prostate cancer, the 5-year success rate with proton therapy was only 73%. For those with high risk disease, the
success rate was only 43% (Slater, 2004). Unfortunately, there have not been any studies looking at outcomes more than 5 years following proton beam treatment. This
is in comparison to our own recently reported long term study showing at 10 years, a 95% success rate with seed implants for
intermediate risk disease, and 83% success rate for high risk disease (Terk 2009). With the seeds being placed directly
in the prostate, higher doses of radiation can be given to the cancer, resulting in a much higher BED (biologically effective
dose). The 20-50% higher BED seen with seed implants results in much greater cancer killing. Seed implants allow the ultimate
concentration of radiation directly in the prostate, while still keeping surrounding areas at the lowest dose possible.

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Proton Radiation - Increased Side Effects
Will I have fewer long term side effects with a seed implant?
YES - because high dose proton beam radiation is delivered externally from a machine, the radiation still must enter the
body from the outside and pass through organs like the bladder and rectum and hips to reach the prostate, causing much greater
side effects than seed implants. A study from a leading proton facility showed that following proton radiation, 41% of men
had long-term rectal bleeding and 47% had long-term bleeding with urination (Gardner, 2002). Long-term incontinence rates after proton radiation still remain unknown.
In contrast to proton beam radiation, long term side effects are very rare with seed implants. Using an intra-operative
dosimetry technique, the likelihood of the seeds migrating outside the prostate is less than 0.4%. Urinary incontinence occurs
in less than 1% of men following a seed implant. Other severe urinary problems are also very rare. (Zelefsky, 2007)
Will seed implants allow for improved preservation of my erectile function?
YES - The best erectile function preservation rates are obtained with seed implants. By pinpointing the seeds directly
in the prostate, there is minimal effect on nerves that help control erections. Studies show that up to 90% of men maintain
their erectile function after a seed implant (Cesaretti, 2007). Erectile function has never been evaluated after proton beam radiation. Because proton radiation needlessly treats outside
the prostate where the nerves reside to a high dose, much greater impotency rates are expected.
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A. A dose map of a prostate being treated with protons shows the excess
radiation deposited outside the prostate. This is what causes the higher side effects.
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B. A similar dose map of a prostate being treated with a seed implant shows
no excess radiation outside the prostate, as the seeds radiate the prostate from within.
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Proton Radiation - Dangers
Why is there a high risk of proton radiation causing a new cancer to
develop?Of great concern, the renowned radiation biologist Dr. Eric Hall reported that the physics of
proton radiation delivery causes excessive neutron contamination in the patient’s body. Neutrons are dangerous
nuclear particles that can damage normal organs. They are known to increase the likelihood of developing potentially
life-threatening secondary cancers. (Hall, 2007). This risk of neutron contamination is much greater with proton radiation than with either IGRT or seed implants.
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Proton Radiation - Salvage Treatment
What are my treatment options if I have a recurrence of my
cancer after proton beam radiation?The Florida Center for Prostate Care has the largest published experience
in the world using seed implants to treat patients with recurrent cancer after prior radiation treatment. Several simple tests
and our review of your records help determine if you are a potential candidate for this highly specialized treatment.
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Questions to Ask if You are Considering Proton Radiation
Men with prostate cancer deserve answers clearly
supported by evidence published in medical journals. 4 questions you MUST ask your proton doctor if you are
considering proton beam treatment:
1. Have you personally published your 10 year proton beam results in a medical journal or presented them at an
international conference?
2. For my stage of prostate cancer, what is the published likelihood that I will be cancer free 10 years after
proton beam radiation? (please show me the articles)
3. Why do experts report my risk for developing a new secondary cancer is greater after proton beam radiation than prostate
seed implants?
4. What is the 10 year published likelihood of maintaining my erectile function and urinary control (continence)
after proton beam radiation?
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1 Bittner - IJROBP, 2008 2 Zelefsky - IJROBP, 2007 3 Slater - IJROBP, 2004 4 Zietman - JAMA,
2005
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