"Should I get proton therapy?" is a question that my patients often ask me, and you may be thinking about it right now. The short answer is that "it depends." Only you and your oncologist should be making this decision.
Before deciding IF you should receive proton therapy, you need to know WHAT it is. Proton therapy is a form of external beam radiation that uses particles (i.e., protons) instead of photons (i.e., X-rays) to treat tumors. Both forms of radiation can destroy cancer cells by messing up their genetic blueprint (DNA). This makes it difficult for cancer cells to continue to grow and divide, and they ultimately die.
In general, the higher the radiation dose, the better the tumor control will be. However, such high radiation doses can affect normal tissue near the tumor, which is what we all want to avoid.
Photons (x-rays) deposit the majority of their dose within the first inch after they hit the skin, and they continue to deposit dose after they reach the tumor. Hitting a deep tumor with just one or two x-ray beams is hard (that would be like trying to power-wash your driveway with a water pick). We often need to use many different beams to cover the tumor and this can result in more radiation exposure to normal tissues. This is where proton therapy has the edge. Protons deposit most of their dose at the tumor and more importantly stop traveling after they hit the tumor. This reduces the radiation dose beyond the tumor, allows the use fewer beams, and subsequently greater sparing of normal tissue.
Proton treatment requires sophisticated machinery and expert professionals to deliver it. The synchrotron will accelerate protons to almost the speed of light for maximal penetration. Inside the synchrotron they may travel 300,000 miles, which is equivalent to circling the earth 12-13 times. The protons are then fed to the treatment gantry, which is a massive 190-ton device that directs the proton beam before it enters the patient. Despite its large size (over 40 feet in diameter), the gantries have a precision of 1mm. We also have a highly trained, dedicated group of professionals who operate and maintain the Proton Therapy Center to ensure that everything works to its best level.
Proton therapy is currently available in only seven centers in North America. MD Anderson has one of the largest and technically advanced centers in the world. We have four treatment rooms, including one of the only centers with spot-scanning (also called pencil-beam scanning) capabilities.
The first patient was treated with proton therapy at MD Anderson on May 4, 2006, and since then we have treated more than 1,700 patients. We have a lot of experience treating patients with lung cancer, esophageal cancer, brain tumors and prostate cancer, as well as various other tumor sites. Also, we're one of the most active centers in the world for treating children with proton therapy.
Since the Proton Therapy Center is part of MD Anderson Cancer Center, we can provide our patients not only with outstanding proton therapy but also outstanding cancer therapy.
So, should you receive proton therapy? Please consult with your radiation oncologist or check out the Proton Therapy Center's website for more information.