There are several different types of treatment for lung cancer. Which are best for you will depend on a number of factors including:

• your general health
• the type of lung cancer (small cell or non-small cell)
• the size and position of the tumour
• whether it has spread beyond the lung (its stage)

Photodynamic therapy (PDT) uses laser light combined with a light-sensitive drug (a photosensitising agent) to destroy cancer cells. It is usually used to treat a type of lung cancer called non-small cell lung cancer (NSCLC).

When treating lung cancer PDT is mainly used for people with:

• early stage lung cancer that hasn't spread outside the lungs. But, who can't have an operation to remove the cancer.
• locally advanced lung cancer, to help to relieve breathless caused by tumour blocking an air passage.

PDT can also be used at the same time as or after other lung cancer treatments such as chemotherapy and radiotherapy.

How PDT is given for lung cancer

You are given an injection, of a light sensitising liquid, into your vein. The liquid travels round the body in the blood and is absorbed more by the cancer than by normal tissues. A few days later you have a bronchoscopy.

The bronchoscopy involves a thin, flexible tube (bronchoscope) being put down your throat and into the airway (bronchus) of the lung where the tumour is. A light source, usually a laser, is then threaded through the bronchoscope and shone on the tumour. The light damages and kills the cancer cells. A few days later you may need to have a second bronchoscopy, to remove the dead cancer tissue and to clean the airways (bronchial tubes).

PDT in early stage lung cancer

PDT may be a treatment option for people who have a non-small-cell lung cancer that hasn't spread to the lymph nodes. But, who can’t have surgery to remove the cancer because they:

• have cancer in both lungs
• had an earlier operation to remove part of their lung
• have a separate lung disease that affects their breathing
• are unfit for surgery because of other health problems
• choose not to have an operation to remove the cancer.

The aim of PDT in early stage lung cancer is to try to cure the disease or to shrink and control it for as long as possible (long term remission). The treatment can be repeated if, in the future, the cancer comes back in the same part of the lung (locally).

PDT isn't suitable for everyone with early stage lung cancer. The tumour has to be in a part of the airway that can be reached with a bronchoscope. It seems to work best for small tumours. This is because the light waves can only go (penetrate) to a certain depth. If the tumour is larger PDT is less likely to be effective.

Alternative treatments may include:

• laser (thermal laser) treatment to destroy the cancer (laser ablation)
• placing radioactive seeds into the lung where the cancer is. This is called internal radiotherapy or endobronchial brachytherapy
• external beam radiotherapy.

Doctors don't know which of these treatments works best. This is because there haven't been studies to compare PDT with other treatments for people with early stage NSCLC. But two small studies found that between 62 and 85 out of every 100 people with early stage lung cancer had no signs of cancer soon after PDT. This is called complete remission.

The National Institute for Health and Clinical Excellence (NICE) have written information for the public on PDT for early lung cancer. See http://guidance.nice.org.uk/IPG137/

This gives more results of studies into PDT. It also tells you what you should know about PDT when deciding whether to have it.

PDT for advanced lung cancer

When doctors use PDT to treat advanced stage lung cancer their aim is to relieve symptoms such as breathlessness and bleeding. This is called palliative treatment. Breathlessness may be caused by the tumour blocking the airway. In this situation PDT works by destroying the tumour and clearing the blockage. Other possible treatments include:

• an electric current being used to destroy the tumour (called diathermy or electrocautery)
• using very cold temperatures to destroy the tumour (cryotherapy)
• radiotherapy to shrink the cancer
• laser therapy to evaporate the cancer
• putting a plastic or wire mesh tube (stent) inside the airway to keep it open.

NICE have produced information for people with advanced lung cancer who are considering PDT. See http://guidance.nice.org.uk/IPG87/

Side-effects of PDT for lung cancer

PDT makes you sensitive to light. If you have it you will need to avoid bright light for some time, so that your skin doesn't burn. This may be for between a couple of days and a few months, depending upon the photosensitizing drug that is used. Other possible side effects include: swelling of the airway, breathlessness and a cough. It is not unusual to cough up blood about four or five days after the treatment but this is not usually a serious problem. There is a risk, for a few people, that PDT could cause a hole in the wall of the airway (fistula).

PDT is still being researched as a treatment for advanced lung cancer and is not suitable for everyone. Your doctor can give you more information. We also have a separate section on PDT.