Radiotherapy is one of the main treatments for prostate cancer. It uses high-energy radiation to damage cancer cells so they can no longer grow and divide. It can be used to cure cancer that is confined to the prostate, treat cancer that has spread locally, or help relieve symptoms if the cancer has spread to other parts of the body.

The main types include:

1. External beam radiotherapy (EBRT) – the most common type.
   • Radiation is delivered from a machine outside the body.
   • Treatment is painless and usually takes only a few minutes per session.
   • A course may last from around 1 week to 8 weeks, depending on the treatment plan and the stage of the cancer.
   • Modern techniques such as Intensity-Modulated Radiotherapy (IMRT) and Image-Guided Radiotherapy (IGRT) allow higher precision while reducing radiation to nearby organs.
2. Brachytherapy (internal radiotherapy)
   • Radioactive material is placed inside or near the prostate.
   • It may involve:
     • Low-dose-rate (LDR) brachytherapy, where tiny radioactive seeds are permanently implanted.
     • High-dose-rate (HDR) brachytherapy, where radioactive sources are temporarily inserted and then removed.
   • It may be used alone for lower-risk cancers or combined with external radiotherapy for higher-risk disease.

Before treatment

Before radiotherapy, you’ll have a planning appointment called a CT simulation. This helps the treatment team map the exact area to treat while protecting healthy tissue. You may also have an MRI scan to improve accuracy.

Effectiveness

Radiotherapy is highly effective for many men with:

• Localised prostate cancer (confined to the prostate)
• Locally advanced prostate cancer (spread just beyond the prostate)

For many patients, cure rates are comparable to surgery, although the choice between treatments depends on factors such as:

• The stage and grade of the cancer
• Your age and general health
• Urinary and bowel function
• Personal preferences regarding side effects

Common side effects

During or shortly after treatment:

• Tiredness (fatigue)
• More frequent urination
• Burning or discomfort when passing urine
• Needing to urinate urgently
• Loose stools or bowel irritation
• Mild rectal bleeding or discomfort

Longer-term side effects can include:

• Erectile dysfunction
• Persistent urinary problems
• Ongoing bowel changes (less common with modern techniques)
• Rarely, narrowing of the urethra or bladder irritation

Many side effects improve over time, and treatments are available to help manage them.

Hormone therapy

For men with intermediate- or high-risk prostate cancer, radiotherapy is often combined with androgen deprivation therapy (ADT) (hormone therapy). ADT lowers testosterone levels, making radiotherapy more effective. Depending on the cancer, hormone therapy may be given for several months to several years.

Follow-up

After treatment, you’ll usually have:

• Regular PSA blood tests to monitor your response.
• Follow-up appointments to discuss any side effects or symptoms.

Unlike surgery, the PSA level usually falls gradually over months or even a couple of years after radiotherapy, rather than dropping immediately.