Proton Therapy
Penn Medicine's Roberts Proton Therapy Center is the largest and most advanced facility in the world for this precise form of cancer radiation. At Penn Medicine, patients have access to one of the most sophisticated weapons against cancer, seamlessly integrated with the full range of oncology services available at Penn's Abramson Cancer Center.
Diagnosed with Prostate Cancer?
Neha Vapiwala, MD, chief of the genitourinary service for Penn Radiation Oncology, discusses proton beam therapy for prostate cancer, an exciting form of radiation therapy offered at Penn's Roberts Proton Therapy Center.
Proton therapy is external beam radiotherapy in which protons are directed at a tumor. The radiation dose that is given through protons is very precise, and limits the exposure of normal tissues. This allows the radiation dose delivered to the tumor to be increased beyond conventional radiation. The result is a better chance for curing cancer with fewer harmful side effects.
Proton therapy, like all forms of radiation therapy, works by aiming the energized particles, in this case protons, onto the target tumor. These particles damage the DNA of cells, ultimately causing their death.
Unlike X-rays, protons can be manipulated to release most of their energy only when they reach their target. With more energy reaching the cancerous cells, more damage is administered by each burst of radiation.
How Proton Therapy Works
The cancer-seeking proton beam at the Roberts Proton Therapy Center begins inside a cyclotron, a machine just slightly bigger than an SUV weighing 220-tons: as much as a 747 jetliner. The cyclotron uses powerful magnets to strip protons from the hydrogen atoms in water and accelerate them at higher and higher velocity around a circular path, like cars on a racetrack.
When the protons reach their top speed and highest energy, they're directed out of the cyclotron by other magnets into a beamline: an airless tube that runs for about the length of a football field. At various points along the beamline, the proton beam is channeled by other magnets into the five treatment rooms. Four of the rooms are equipped with a 90-ton gantry, a rotating steel structure that moves around the patient to aim the beam at any angle. (The fifth treatment room uses a "fixed beam," around which the patient is positioned as needed.)
Inside the treatment room, the proton beam exits the beamline through the "nozzle" where a multileaf collimator precisely tunes the energy of the beam and actually shapes it to match the unique profile of the patient's tumor, delivering the most effective dose exactly where it's needed.
The Possible Advantages for Patients
There are several possible advantages to proton therapy, including:
- Same tumor killing properties as X-rays
- Decreased dose to normal tissues
- Decreased side effects and complications
- Treating tumors close to critical organs, like the spinal cord
- Increasing the safe dose delivered to tumors
- Increased cure rates
- Ability to re-treat tumors after recurrences
- Added ability to treat benign conditions
OncoLink Proton Therapy Clinical Trials Matching Service
Patients can search for proton therapy clinical trials that match their specific diagnosis and treatment history using OncoLink's Proton Therapy Clinical Trials Matching Service.
Learn more about searching for proton therapy clinical trials
