Radiation therapy is a method used to kill cancer. The goal is to get as close to the cancer without harming healthy tissue around it. This can be given:

  • As the first method instead of surgery
  • After surgery to kill any cancer cells left behind
  • To ease problems from cancer that has spread and help you live longer

There are different types.

External Beam

Radiation is made by a machine outside the body. Short bursts are aimed at the cancer. These types are:

  • 3D conformal radiation therapy (3D-CRT)—The prostate is mapped. Once the cancer is found, the beams can be aimed at it.
  • Intensity modulated radiation therapy (IMRT)—A machine rotates around the person to send beams to the site. The dose can be made stronger or weaker. This will depend on where the target is. One more type is called volumetric modulated arc therapy (VMAT).
  • Stereotactic body radiation therapy (SBRT)—Uses imaging to send larger doses to the cancer site. The larger doses can make the treatment time shorter.
  • Proton beam radiation therapy—These beams can be sent in larger doses. This is because the aim is more precise.
Radiation of a Tumor
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Seeds are implanted inside the body near the cancer site. They're placed in the prostate between the scrotum and anus. Higher doses of radiation can be used with this method. The seeds can be:

  • Permanent—Low-dose seeds are placed. They emit radiation. They can be used over for a longer time. In some, it may be months.
  • Temporary—A high-dose is sent into the body via tubes. Radiation is given for up to 15 minutes, then it's taken out. This may be given up to 3 times over the course of 2 days. The tubes stay in place until you no longer need to be treated.

In some cases, you may need more than one type.

Radiopharmaceutical Therapy

Alpha emitter radiation therapy is delivered to the cancer through an IV. It’s used to kill cancer that’s spread to the bones.

Side Effects and Management

Radiation aimed at the pelvis causes irritation. You may have:

  • Erectile dysfunction
  • Blood in the stool
  • Pain during bowel movements
  • Diarrhea
  • A harder time holding urine
  • To pass urine more often
  • Narrowing of the tube that carries urine out of the body from the bladder—rare

There are many ways to treat these problems. Other common issues are dry, sore skin, nausea, vomiting, and feeling tired because of anemia. Talk to your healthcare team as soon as these appear so they can be better controlled. In some cases, the dose of radiation may be changed.

Revision Information

  • Reviewer: EBSCO Medical Review Board Mohei Abouzied, MD, FACP
  • Review Date: 09/2018 -
  • Update Date: 10/30/2018 -