Also see, Florida Prostate Center, Proton Therapy.

Will proton irradiation improve my likelihood of Cure?

Absolutely Not. Cure rates for proton therapy are 10 to 40% inferior to a combination of brachytherapy and external beam radiotherapy. Brachytherapy (seeds) has the distinct and unique advantage of having the radioactivity placed directly into the cancer. Thus, the dose is concentrated where it needs to be without the unnecessary irradiation of normal tissue inherent in using any form of external treatment. This is why most FROG patients who can undergo anesthesia are offered a seed implant as a part of their prostate cancer therapy.

Will proton irradiation allow for improved preservation of my erectile function?

No. There are multiple factors that predict for long term preservation of erectile function such as your age, current erectile function, and other medical problems such as diabetes and high blood pressure. Taking these other factors into account, the best rates of erectile preservation are found in patients treated with brachytherapy (seeds).

Will I have lower long term urinary side effects from protons radiotherapy?

No. Severe long-term side effects are rare with all forms of irradiation: Most studies report rates of less than 5%, with no advantage to proton irradiation. Brachytherapy is the only form of treatment that allows for selective sparing of the urethra, whilst delivery of sufficient dose to the cancer containing-tissue.

Will I have lower rectal side effects with proton radiotherapy?

Again, the risk of long-term rectal side effects is rare with all forms of radiotherapy. In the only direct comparison between proton radiotherapy and x-ray (photon) radiotherapy published in the Journal of the American Medical Association, the likelihood of severe rectal side effects was 1% for all patients regardless of the kind of radiation they received. Protons were associated with a doubling in the risk of Grade 2 rectal side effects—where patients have excessive rectal mucous production or an increased frequency of bowel movements.

What is the risk of Second Cancer from Proton Radiotherapy?

There is an excessive production of neutron particle contamination in proton beams produced by passive modulation. Neutrons are highly damaging particles that have an enhanced ability to damage normal tissue and are known to increase the likelihood of developing second cancers. As with other aspects of proton radiotherapy, there is little published on this effect and thus it is difficult to fully quantify the risk. Neutron production is not a factor with conventional x-ray (photon) radiation treatment techniques.

What are my options if I have a recurrence of cancer after proton radiotherapy?

The options depend upon whether or not your recurrence is localized to your prostate gland. Rarely, a prostatectomy can be attempted, although the complication rate is high. Alternatively, FROG has the largest experience in the world using brachytherapy (seeds) to treat patients with locally-recurrent cancer after prior treatment. For patients with recurrence outside the gland, or those unable to get a seed implant, hormone therapy may be useful, although not curative. FROG participates in many national clinical research trials investigating new options using drugs and vaccines to help treat patients with widespread tumor recurrence.

Summary:

The best cure rates for prostate cancer confined to the gland, with the lowest risk of side effects, are achieved through treatment utilizing standard x-ray and/or brachytherapy techniques. Brachytherapy allows the ultimate concentration of radiation directly in the prostate, keeping external organs at the lowest dose possible. In addition, brachytherapy is accomplished in a single one-hour outpatient procedure, opposed to the nine weeks of daily treatment required for proton therapy.

Also see, Florida Prostate Center, Proton Therapy.