Understanding Radiation Therapy Types

Posted on: 18 November 2016

If you learn that you need radiation therapy as part of your cancer treatment, you'll also soon discover that not all radiation therapy treatments are the same. There are many different types of treatment, and your treatment plan could utilize one or a combination of many different kinds in order to be most effective. Here are the most common types of therapy and how they might be used.

External Beam Radiation

External beam radiation is by far the most common radiation type. It has several different subtypes that are directly specialized for the type of cancer you are fighting. External beam radiation (EBR) directs the beam from outside your body. Radiation of this type is applied over the course of many sessions to help you avoid as many negative side effects as possible. One of the more advanced types of EBR is three-dimensional conformal radiation therapy.Your specialist will use a 3D image of the targeted tumor generated from a combination of MRI, CAT and PET scans to more accurately tailor the radiation beams to only the tumor itself, leaving the surrounding tissues and organs with less injury from radiation.

Another exciting form of EBR is proton therapy, which uses protons instead of x-rays. The damage to neighboring tissues with proton therapy is even less pronounced. Similarly, neutron beam therapy can also be effective. However, this type of radiation is only used on tumors that are resistant to damage from x-rays. It can be very destructive to healthy tissues, so it is a much rarer form of radiation only used in more extreme cases. 

Systemic Radiation

Systemic radiation leaves the x-rays alone and instead takes radiation into the body for cancers that are systemic in nature. For example, radioactive iodine is a typical treatment for thyroid cancer. Other cancers, like bone cancer, can be treated with IV radiation, where the radioactive particles are specifically designed to attach to cancer cells and irradicate them while doing little harm to healthy cells. Systemic cancers are difficult to treat without a targeted approach, so this type of radiation therapy is invaluable for patients with no other treatment options. 


This type of treatment is a direct-delivery radiation method. Instead of directing beams at the tumor, a surgeon will instead place a radioactive material in the tumor itself. The direct release of radiation from the material targets cancer cells. Sometimes, the item remains in the body and it becomes less harmful as it ages. In other cases, the device is left in your body long enough to do the job needed for fighting the tumor, and then it is removed before it can damage other healthy tissues. 

Intraoperative Radiation Therapy

Sometimes, it is impossible to use external beam radiation on a tumor because vital organs are too close to the tumor itself. You cannot treat the tumor with radiation without doing irreparable harm to an organ that is keeping you alive. In these cases, intraoperative radiation is especially useful. The surgeon operates by removing the organ that would normally be affected by the radiation therapy. The radiation specialist applies the needed dose of radiation, either with a beam or with brachytherapy. After the radiation treatment is complete, the organ is returned to its normal place. 

Radiation is one of the catch-22 treatment methods for cancer. It can help to shrink or destroy a tumor, but in the process, it can also harm healthy tissue and cause a myriad of other health problems down the road. The above therapies have been developed to help harness the useful power of radioactivity while eliminating its scary side effects as much as possible. If you have questions about your specific treatment plan and how it works, contact a radiation specialist in your area.