Photodynamic therapy (PDT)

Photodynamic therapy is also called PDT or light activating treatment. It kills cancer cells by using a combination of a light sensitising drug and a very bright light.

You normally have PDT as a day case procedure in the endoscopy unit of the hospital. It usually takes about 30 minutes.

You can have PDT along with other types of lung cancer treatment.

When you have it

You might have photodynamic therapy if you have one of the following:

  • a small early stage non small cell lung cancer and you are not having surgery
  • tumours in both lungs
  • you can’t have an anaesthetic due to other medical conditions
  • your cancer has come back after surgery

This treatment can also shrink a tumour that is blocking an airway. It can relieve breathlessness and other problems, such as a cough or coughing up blood.

Before your treatment

Your doctor or specialist nurse explains what happens and how they do the treatment. They ask you to sign a consent form saying that you agree to have the procedure. You can ask them any questions that you have. Tell them about any medicines you are taking.

You have a medicine that makes cells sensitive to light and then you go home. You might have the medicine as a liquid that you swallow or you might have it as an injection through a small tube in a vein in the back of your hand.

The light sensitising drug circulates throughout your body. So your skin and eyes become sensitive to light. You need to avoid bright sunlight and bright indoor light.

When you go outside, you must cover all your skin and wear sunglasses.

Two to three days later, you go to the endoscopy department at the hospital.

Having photodynamic therapy

You shouldn’t eat or drink anything except water for 4 to 6 hours before the treatment. You can drink water until 2 hours beforehand.

A nurse puts a small tube called a cannula into a vein in the back of your hand. They go with you to the endoscopy department or x-ray department.

You have a medicine to make you sleepy injected into the cannula. Or you might have a general anaesthetic.

When you’re very sleepy or asleep your doctor gently puts a long flexible tube called a bronchoscope into your airways. The tube has a small camera on the end so they can see the cancer. They position the end of the tube close to the tumour and shine a low power laser light at it.

Diagram showing a bronchoscopy

The light activates the drug to destroy the cancer cells. The doctor takes the bronchoscopy tube out.

After photodynamic treatment

You stay in the endoscopy department or x-ray department until the sedation or anaesthetic wears off. You might wear an oxygen mask for a short time. A nurse then takes you back to your ward. You can usually go home that evening.

Removing the dead cells

A few days after the treatment your doctor might need to remove the dead cells from your airway. They do this using an endoscopy tube.

Possible risks

Photodynamic therapy is a safe treatment but all treatments have potential risks.

A member of the team will go through the potential risks and benefits of the procedure with you.

Side effects

Sensitivity to light

The sensitivity to light can last for 6 weeks or more.

Avoid bright sunlight and bright indoor light. And cover all your skin and wear sunglasses if you go outside.

Your skin can get red, blistered or swollen if you’re exposed to bright light. Tell your nurse or doctor straight away if this happens.

Soreness and pain

You might have a sore throat or chest pain. Taking painkillers for a few days helps. Tell your nurse or doctor if you still have pain.

Feeling sick

Let your nurse or doctor know if you feel sick. They can give you medicines to reduce sickness.


You might have some slight bleeding and have some blood in your sputum (phlegm). It might give you a metallic taste in your mouth. This usually gets better over a few days.

Tell your doctor if you cough up blood.

If the cancer blocks the airway again

If the tumour grows back and blocks your airway you can have PDT again. Or your doctor might suggest other treatments.

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