To many individuals, the management of prostate cancer seems full of confusion. Much of this confusion comes from the many options available for treating a newly diagnosed patient. Sadly, very few studies have been done to really know whether any treatment is better than the others.  One of the major problems with some of the options is the absence of long-term follow-up. Proton Beam Therapy (PBT) is one of the treatments suffering from this problem. PBT differs from conventional radiation therapy by using tiny particles fired at very high speeds to attack the cancer cells. Its main advantage is the potential to deliver less radiation to the surrounding tissue — which may result in fewer side effects.

So far the studies look good for pediatric tumors, however, the results for prostate cancer are much less clear.  The fact is, at this time there is no proof that PBT is better or safer than conventional radiation.  While there are no clear advantages, there are several clear disadvantages such as; PBT is much more costly than conventional radiation and there are a limited number of centers offering this treatment in the U.S.  Limited treatment centers mean that a patient will have to travel and and stay nearby during the 6-8 weeks needed to complete the therapy.

Adding to the confusion is the extensive publicity that regularly appears in the media.  Recently, a major institution announced its forthcoming center and the local newspaper wrote an article highlighting some of the controversies.  There are also inconsistent policies about payment.  The American Cancer Society has an excellent summary of PBT and it should be read by anyone considering this option.

For those wanting some specific facts about the results, here is what we know.  First, the longest follow-up available has been from California but they only reported PSA failure rates at seven years without any information about long-term survival.  Using PSA as a surrogate for success is not an acceptable measure and it can deliver incorrect conclusions.  So, at this time, we do not know how well it works long-term.  Also, PBT by itself has not yet been compared to conventional radiation in a properly done randomized study.  However, one recent uncontrolled analysis found more GI side effects with PBT compared to Intensity Modulated Radiation Therapy (IMRT).

In my opinion, I believe there is a problem is the way new treatment technologies are introduced for treating patients with different diseases. We require new technologies to be proven safe, but ironically it is not necessary to show how well such technologies works.  Fortunately, this is not the case for new drug therapies, for which benefit must also be established; although the necessary information about effectiveness comes later and is rarely derived from well-done studies.  That means many people get the treatment without knowing if it works as well as the hype would suggest.

The bottom line, for now, is to be aware of the limitations that exist for PBT, rather than be swayed by the theoretical hype and extensive marketing.   If studies can actually prove it has advantages then it may be worth the higher cost; but until that occurs, it makes no sense to pay more for a treatment that offers no proven advantages over conventional radiation.