Pencil Beam Technology

Pencil-Beam Scanning — The Latest Technology in Fighting Cancer

At the heart of Scripps Proton Therapy Center lies a sophisticated piece of equipment called a cyclotron. With imaging tools located under one roof, patients can reduce the number of appointments at the center and travel time to other imaging facilities.

Pencil-Beam Scanning — The Latest Technology in Fighting Cancer

Scripps Proton Therapy Center uses the latest, most advanced technology available to help in your fight against cancer. Pencil-beam scanning technology enables clinicians to precisely manipulate and direct the proton beam so that its energy conforms exactly to the unique size and shape of the tumor. Scripps Proton Therapy Center is the first in the nation to offer all-pencil beam proton technology in each of our five treatment rooms.

The center’s pencil-beam technology allows physicians to fine-tune the range and intensity of the proton beam. Unlike earlier proton scattering techniques, pencil-beam scanning further enhances the precision of the technology by sweeping a narrow proton beam across the tumor in fine strokes, building up the dose layer by layer.

What does this mean for patients? That a high dose of cancer-killing radiation is directed to the tumor with precision — minimizing radiation exposure to surrounding healthy organs and tissues. Pencil-beam scanning is especially ideal for complex cancers in which the tumor is located near critical structures.

Benefits of proton therapy include:

  • Precision
    Protons can be manipulated to stop and deliver radiation directly at a tumor — and travel no further.
  • Radiation dose variation
    Proton therapy also allows physicians to vary the intensity of the radiation dose at any point within the tumor, which previously was not possible. See Bragg Peak.
  • Treatment for many tumor types
    Pencil-beam scanning expands the treatment options to treat larger and more irregularly shaped tumors. It also allows more types of tumors to be treated compared to passively scattered protons.
  • Minimal side effects
    Because proton therapy spares healthy tissue surrounding a tumor, side effects such as diarrhea, nausea, headache and loss of appetite are less likely. After treatment, most patients may resume their daily routines.

Fast treatment time in all five rooms

At Scripps Proton Therapy Center, we understand that patients want to get back to their lives and families. With older passive scattering proton technology, multiple physical devices are designed for each patient and fitted onto the treatment nozzle. These devices are heavy, cumbersome, and can take days to manufacture. With pencil-beam scanning, the treatment plan is loaded into the computer, and then a beam of protons is painted onto the tumor with laser-like precision. Most patients are treated within a matter of minutes.

Cutting-edge proton therapy system

The center features one of the largest proton systems in the country, which includes a cyclotron, beamline, two fixed beam treatment rooms and three rotational gantry treatment rooms.

Proton Therapy Cyclotron 250x166
The 90-ton cyclotron device generates about 5 trillion protons per second, then accelerates protons outward from the center along a spiral path at roughly 100,000 miles per second.
Proton Therapy Beamline 250x166
The beamline is a beam transport system that spans the length of the building and is used to transport the proton beam from the cyclotron to any of the five treatment rooms. It uses a series of magnets to bend and focus the beam to the treatment room when treatment is ready to begin.
Proton Therapy Gantry 250x166
Rotational gantry
The gantry is a 280-ton machine that rotates around the patient to deliver protons through a specialized nozzle. The three-story tall structure rotates 360 degrees around the patient to ensure the ideal treatment angle. The gantry is mechanically precise to less than a millimeter.