Side effects of radiotherapy for penile cancer

Side effects tend to start a week after the radiotherapy begins. They gradually get worse during the treatment and for a couple of weeks after the treatment ends. But they usually begin to improve after around 2 weeks or so.

These side effects vary from person to person. You may not have all of the effects mentioned. We don't cover all the possible side effects here. Your team will talk with you about possible side effects before you start radiotherapy treatment.

Tiredness and weakness

You might feel tired during your treatment. It tends to get worse as the treatment goes on. You might also feel weak and lack energy. Rest when you need to.

Tiredness can carry on for some weeks after the treatment has ended but it usually improves gradually.

Various things can help you to reduce tiredness and cope with it, such as exercise. Some research has shown that taking gentle exercise can give you more energy. It's important to balance exercise with resting.

Skin changes or skin soreness

Your skin might go red or darker in the treatment area. You might also get slight redness or darkening on the other side of your body. This is where the radiotherapy beams leave the body. 

The red or darker areas can feel sore. You may notice that it is itchy or feels warm to touch. During treatment your skin may also become dry and flaky, or can ooze and be painful. Do let your radiotherapy team know, they can help you cope with these symptoms.

The symptoms usually go away within 2 to 4 weeks of ending the treatment. But your skin might always be slightly darker in that area.

Tell the radiotherapy staff if you notice any skin changes.

 Tips for looking after your skin during radiotherapy

  • Wash or rinse the area with warm water. Showers are preferable to baths.
  • Gently dry the skin with a clean towel.
  • You can use a moisturiser on the area (but avoid using creams with perfumes). Check with your radiographer if you are unsure, they may be able to give you a soothing gel or recommend particular type.
  • Wear loose fitting clothing made of natural fibres, such as cotton. This can help reduce irritation to the area.


Your penis might become swollen and inflamed. This swelling can cause pain. Tell your doctor, nurse or radiographer if you have pain so that they can give you painkillers. The swelling goes down when you finish your treatment.

Side effects if you have chemotherapy with radiotherapy (chemoradiotherapy)

Chemotherapy combined with radiotherapy can make some side effects worse. Speak to your doctor or nurse if you are worried about side effects.

Long term side effects

Most side effects gradually go away in the weeks or months after treatment. But some side effects can continue or might start some months or years later.  

Last reviewed: 
09 Feb 2021
Next review due: 
09 Feb 2024
  • Guidelines on Penile Cancer

    OW Hakenberg and others

    European Association of Urology (EAU), 2018

  • Principles and practice of oncology (10th edition)
    VT De Vita, S Hellman and SA Rosenberg
    Lippincott, Williams and Wilkins, 2015

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