Types of Radiation Therapy

Types of Radiation Therapy

About half of all Los Angeles cancer patients receive one or more types of radiation therapy during the course of their treatment. Doctors will prescribe one of the different types of radiation therapy as a standalone cancer treatment. They could also suggest a combination of chemotherapy and radiotherapy depending on your situation. No two patients’ conditions, tumor size, location, and stage are the same, requiring each treatment plan to be unique. The CyberKnife System used at Pasadena CyberKnife delivers the most advanced form of radiation therapy, called Stereotactic Radiosurgery (SRS) for the brain and spine and Stereotactic Body Radiotherapy (SBRT) for the rest of the body. Although it might sound like a surgical tool, CyberKnife actually performs robotic radiosurgery, a non-surgical and non-invasive method of delivering very high dose radiation to cancer cells, with extreme accuracy while keeping healthy cells undamaged. CyberKnife treatment leaves patients with minimized side effects and an increased quality of life.

Types of Radiation Techniques

Radiation therapy is delivered either through external beams or by brachytherapy, which involves placing radioactive elements in the form of tiny wires or seeds next to a malignant tumor. With the exception of proton therapy, Pasadena CyberKnife offers all the below radiotherapy treatments.

Three-Dimensional Conformal Radiation Therapy (3D-CRT)

3D-CRT relies on imaging tests to map out radiation treatment. Based on what’s shown on the imaging tests, doctors deliver external radiation beams from multiple angles to destroy cancer cells, but relying on imaging tests alone doesn’t always allow doctors to deliver treatment with pinpoint accuracy. Also, 3D-CRT techniques require patients to be placed in immobilizing devices so that they can’t move during treatment.

Intensity-Modulated Radiation Therapy (IMRT)

Like 3D-CRT, IMRT machines rely on imaging tests to create a radiation treatment pathway. These machines, in addition to delivering external radiation beams from multiple angles, can deliver beams of different intensity to different parts of a tumor. One type of IMRT, called volumetric modulated arc therapy (V-MAT), delivers an IMRT treatment as a machine rotates once around the body. Although patients are immobilized for shorter periods of time with V-MAT, the immobilization techniques can make this treatment uncomfortable for patients.

High-Dose/Low-Dose Rate Brachytherapy

Some doctors use brachytherapy, which involves surgically placing tiny pieces of radioactive material near a tumor. However, the surgery required to place these radioactive wires and seeds can be painful. For example, to treat prostate cancer with brachytherapy, doctors have to surgically place tiny wires through the rectum and into the prostate.

Stereotactic Body Radiation Therapy (SBRT)

SBRT is also called stereotactic radiosurgery (SRS), even though no actually cutting ever happens. It uses machines, to perform image-guided radiation therapy (IGRT). Using these precise computer images, oncologists can deliver short bursts of radiation to tumors in different parts of the body. There are several types of machines that perform radiosurgery, but most, with the exception of CyberKnife, require immobilization, breath holds, or gating and have differing levels of precision. CyberKnife can deliver radiation dosages with pinpoint precision. Also, because of its unique robotic design, CyberKnife can adjust to patient movements almost instantly. This flexibility means that patients who get CyberKnife treatments don’t have to be placed in immobilization devices and instead lie comfortably on the treatment couch during each short session.

Intensity-Modulated Proton Therapy (IMPT)

IMPT, also known as proton therapy, uses protons instead of photon beams to deliver external radiation to cancer cells. However, the machines that deliver proton therapy are extraordinarily expensive, and they require dedicated expert usage and maintenance. Because of the expense and lack of supporting clinical data, very few cancer treatment centers in Los Angeles currently use proton therapy, and insurers don’t always cover it. Dr. Mak has experience with IMPT, but Pasadena CyberKnife doesn’t offer the treatment.

How CyberKnife Works

The CyberKnife System combines robotics with extremely sophisticated software to target your cancer cells down to the sub-millimeter. While other systems are capable of real-time tracking, only CyberKnife is also able to accurately target and treat cancer cells as the body naturally moves. By targeting multiple radiation beams from hundreds of angles at an extremely focused point, and adjusting seamlessly to patient movements thanks to its intricate robotic arm design, CyberKnife destroys cancer cell DNA while leaving surrounding healthy cells undamaged.

Some of the biggest benefits of CyberKnife radiosurgery include:

  • Industry-leading accuracy. CyberKnife’s imaging capabilities, tumor-tracking software, and dedicated robotic design ensure that radiation treatments are delivered with extreme precision. Before delivering a radiation beam, CyberKnife take an image of the tumor, ensuring that radiation beams are delivered to the precise location of the cancer cells. Other machines are limited to delivering radiation beams within a 360-degree plane. CyberKnife’s robotic arm lets oncologists target cancer cells from almost any angle without limiting their options.
  • Minimal side effects and fast recovery. By offering cancer treatment with minimal or no side effects, CyberKnife lets patients enjoy their normal activities both during and after radiation treatment. Most patients leave our outpatient center after their treatment and go right back to their regular activities. The few patients that experience side effects, like some mild aches and pains, usually report that discomfort disappears within a week or two of treatment.
  • Pain-free. With CyberKnife, you’ll experience no surgical incisions and no blood loss. In fact, most patients experience no sensation at all.
  • No anesthesia. With CyberKnife, you’re awake throughout the whole session, which in most cases lasts less than an hour. Without anesthesia, you have a lower risk of complications than you have with traditional surgery.
  • No hospital stay. All CyberKnife treatments in Los Angeles happen on an outpatient basis, meaning you won’t have to stay in the hospital overnight. In fact, our patients typically go home right after they finish a treatment.
  • No long-term treatments. Some types of radiation therapy require regular doctor visits for as many as eight weeks. CyberKnife treatments are delivered in short sessions over just one to five days.

What to Expect During a CyberKnife Session

CyberKnife is one of the most convenient radiation therapy treatment types. You’ll need one to five short treatments completed in less than a week.

Before Your Treatment

A high-resolution CT scan will be taken before your first treatment session to determine the exact size, shape, and location of your tumor. The scan is uploaded into the CyberKnife System and our team, consisting of a radiation oncologist and medical physicists, will design your unique treatment plan.

During Your Treatment

You’ll lie on the comfortable treatment couch while the CyberKnife machine moves slowly around you. You won’t feel anything as the pinpoint-accurate radiation beams focus on destroying the cancer cells within your body, and you won’t have to wear uncomfortable restraints, such as head frames for brain tumors that are pinned to your skull or abdominal compression devices to limit your body’s movements.

After Your Treatment

When your treatment session ends, you’ll go home. Most people continue their daily activities without noticing any effects from their CyberKnife treatment. When you’ve completed all of your sessions, you’ll follow up with us or with your own oncologist.

Contact Pasadena CyberKnife

Contact our Los Angeles center today at 628-768-1021 or fill out our contact form to schedule a consultation or to answer any questions you have regarding cancer treatment.