Radiation oncology, also called radiotherapy or radiation therapy, involves treating cancer with beams of high-energy radiation. You may be familiar with the use of radiation in the form of diagnostic chest X-rays, computerized tomography (CT) scans or dental X-rays. Radiation therapy relies on much higher X-ray energy delivered at many more times the amount of a regular X-ray in order to treat cancer.

Sarah Cannon Cancer Institute at Centerpoint Medical Center perform radiation therapy during your cancer treatment for different reasons, including:

  • Neoadjuvant therapy (before surgery, to shrink a cancerous tumor)
  • During surgery, to direct large doses of radiation directly at a tumor
  • Adjuvant therapy (after surgery, to stop the growth of any remaining cancer cells)
  • In combination with other treatments, such as chemotherapy
  • Palliative care (decrease pressure or pain that the tumor puts on you)

In external radiation, treatment comes from a machine outside your body. This radiation comes from a machine called a linear accelerator. Linear accelerators deliver external beam radiation which is most often targeted to a specific area of your body. Typical radiation therapy is on an outpatient basis about 5 days a week over a period of 1-8 weeks. Treatment sessions last approximately 30 minutes.

Radiation oncologists, therapists, physicists, and equipment specialists perform safety checks at every step of the treatment process - from the day radiotherapy machines are installed to the planning and delivery of treatment.

These checks ensure that radiation therapy treatments are appropriate and customized for each patient. They provide an opportunity to review every patient's treatment plan and make modifications as necessary. They also create an environment where safety - and its improvement - is an intrinsic part of treatment.

Frequently asked questions about radiation therapy safety measures

  • What safety measures are in place to catch and prevent errors?
  • What safety checks are performed by staff?
  • How do we know these checks are sufficient?
  • What is the inspection and certification program for radiation therapy machines?
  • How is the number of therapists involved in the treatment plan determined?
  • What level of reporting is required by the State regulatory agencies?

What safety measures are in place to catch and prevent errors?

The linear accelerator (LINAC), the machine that delivers radiation therapy to patients, has redundancy systems to control and monitor radiation doses and direction. These systems shut off the LINAC if it is not performing to specifications.

All LINACs undergo an extensive set of quality assurance measurements to ensure that radiation therapy is delivered correctly and that the system for planning radiotherapy treatments is fully in sync with each LINAC. This is followed by a schedule of daily, monthly, and annual tests to monitor LINAC performance.

A system of independent checks is in place to verify that the calculations used to program the LINAC and position each patient are correct.

All new treatment plans are examined by clinical staff during meetings known as chart rounds. During these meetings, physicians, treatment planners, physicists, and radiation therapists perform peer reviews of treatment plans and patient charts.

All patients on treatment are monitored by physicians at regular intervals over the course of their therapy.

Patient positioning is regularly verified with X-ray films, which are reviewed by attending physicians.

A non-punitive safety reporting system encourages any member of the department to report errors or near misses. All such reports are reviewed by the multidisciplinary quality improvement committee. This committee suggests improvements in department processes and communicates with hospital safety committees as well as the Kansas and Missouri Radiation Control Programs and the Nuclear Regulatory Commission (NRC).

What safety checks are performed by staff?

Safety checks are conducted by staff at every phase of machinery operation and treatment planning and delivery. They include:

Linear accelerator safety: Before a LINAC is placed in service, an extensive set of acceptance and commissioning measurements ensures that the machine is working properly and complies fully with the treatment modeling system. These measurements are verified by an independent assessment by the Radiological Physics Center, which provides auditing services to radiation oncology departments across the country.

Every morning, staff conduct safety checks of the machinery's dose calibrations and body-positioning features. More detailed checks of mechanical and imaging equipment are conducted monthly, and comprehensive testing is performed annually.

Treatment planning: Radiation therapy physicists conduct independent reviews of all patients' treatment plans. Intensity modulated radiation therapy (IMRT) plans are first delivered on a test basis to a plastic model to ensure the LINAC will deliver the planned treatment accurately.

Treatment delivery: Settings for the dose and shape of the radiation beam are automatically transferred from the treatment planning system to the LINAC to avoid transcription errors or miscommunications. A Record and Verify system ensures the LINAC is programmed as planned and logs the delivery of treatment. The Record and Verify system will not allow the LINAC to treat a patient if it is programmed differently than the treatment plan.

Video monitors enable staff to view radiotherapy treatments in progress. An automated bar-coding system ensures proper patient identification, both as the patient enters the department and as treatment information is displayed on the LINAC. A mandatory safety pause occurs prior to first treatment.

Chart checks: Patient medical charts receive an initial review by a Medical Physicist. During chart or new patient rounds, all patient charts and treatment plans are peer-reviewed by all Radiation Oncologists and staff.

Separate chart reviews are conducted on all brachytherapy cases, in which radioactive "seeds" are placed in cancerous tissue. Medical physicists check patient charts weekly and after the conclusion of treatment. Physicians assess patients throughout their treatment and review verification films that confirm patient set-up at least weekly.

How do we know these checks are sufficient?

Sarah Cannon HCA Midwest Health maintains a quality assurance system for reporting adverse events and near misses. All such events are reviewed by the department's Quality Improvement Committees and are reported to the hospital safety committees and state regulators when appropriate. Such incidents may trigger a Root Cause Analysis, in which specialists investigate the causes of the problem and formulate plans for preventing it in the future. Our safety record is well documented and very good, but we constantly strive to improve it.

What is the inspection and certification program for radiation therapy machines?

Every morning staff conduct safety checks of the machinery's radiation output, beam shaping devices, imaging, and body-positioning features. More extensive tests are carried out according to a schedule of weekly, monthly, and annual measurements.

Manufacturer engineers trained in LINAC systems perform preventive maintenance on a quarterly basis following the guidelines of the LINAC manufacturer and can be brought in as needed.

How is the number of therapists involved in a treatment plan determined?

We staff based on the recommended guidelines of two therapists per procedure. Each machine is staffed by a group of therapists with oversight from a senior therapist.

What level of reporting do our State and National regulatory agencies require?

The Kansas and Missouri Radiation Control Programs require reporting of mistreatments that meet a variety of criteria. These include treating the incorrect patient, the incorrect site, using the incorrect modality, or treatments that deviate from the specifications of the planned treatment.

Radiation is an effective way to treat and, in many cases, cure people with cancer. Of all cancer patients, 60 percent receive radiation at some time during their care. Radiation also may be used to treat people with certain noncancerous conditions.

In cancer treatment, the goal of radiation therapy may be to cure cancer, to control the growth of the cancer or to relieve symptoms. Radiation therapy may be used alone or in combination with surgery, chemotherapy or hormone treatment to achieve these goals.

The delivery of radiation is technically complex and requires a team of highly trained physicians, nurses, physicists, dosimetrists and radiation therapists. Your radiation oncologist is a doctor who specializes in the medical use of radiation to treat patients with cancer.

Planning for Your Day of Treatment

Several steps are involved in planning your radiation therapy.

  1. Simulation is the first step. The purpose is to identify the area to be treated. A dedicated CT simulation machine mimics the movements of a linear accelerator (the machine that delivers the actual treatment). The CT simulator produces diagnostic quality X-rays to verify the position of the anatomy to be treated.
  2. Once simulation is completed, your skin may be marked with small dots of permanent ink ("tattoos") to outline the area of radiation and ensure that the therapists can treat you accurately each day. If needed, custom immobilization devices will be made for you at the time of simulation to help you keep the precise position on a daily basis.
  3. A unique treatment plan is created for each patient using the information gathered during the simulation.
  4. You will return for a "trial run," called a set-up, using the actual treatment machine. You will be placed on the treatment machine in your simulation position. Special X-rays, called electronic portal images or port films, will be taken to show the path of the X-ray beam(s). These will be compared to the plans done by the treatment planning team. If your doctor agrees that this is the most effective plan, you are ready to begin treatment.

Your Daily Treatments

Your radiation oncologist will decide the specific number of treatments you will get based on your type of cancer, its location and your overall treatment plan. Most patients are treated five days a week, Monday through Friday, for one to eight weeks. Some patients are treated twice a day, depending on the type of cancer. The weekend rest permits normal cells to recover between radiation treatments.

Your treatment appointment will generally be at the same time every day.

In most cases, you will need to change into a gown for treatment. Then, you will be escorted into the treatment room by a certified radiation therapist who will administer your treatment.

Overall, you will spend about one hour in the Radiation Oncology Department on a daily basis. Treatment times vary and could range from a few minutes to 30 minutes based on your individual plan. You will not see or hear the radiation and will not feel anything. The process is like having a diagnostic X-ray.

You will be in communication with and viewed by your radiation therapist via an intercom system and monitored at all times during your treatment.

Once the treatment session is completed, your radiation therapist will help you off the table and you can get dressed and resume your normal schedule. You are not radioactive and do not need to avoid other people because of your treatment.

Side Effects

Side effects of treatment, most likely, will relate to the area of the body being treated. If side effects occur during radiation therapy, most can be controlled with medications or diet. They usually go away within a few weeks after the treatment ends. Some patients have no side effects at all.

On-Treatment Visits

Your doctor and primary nurse will evaluate you every week during treatment. They will monitor your progress and help you manage any side effects. This is called an on-treatment visit (OTV) and will occur on a specific day of the week. If you would like to see your doctor or nurse on a day other than this scheduled day, please tell your radiation therapist.

After Your Treatment

At the end of your course of radiation therapy, you will receive post-therapy and follow-up instructions.