Neuro-oncology service: Gliolan®

Gliolan® is a drug containing an active substance called 5-aminolevulvinic acid hydrochloride (5-ALA). Gliolan® is used in adult patients with a type of brain tumour called a malignant glioma. When Gliolan® is taken it is absorbed into the tumour cells.

When the brain is viewed under special light the tumour glows. This is called fluorescence. The use of fluorescent dyes to illuminate cells under specific lights has been used for many years in research.

The active substance in Gliolan® is absorbed by cells in the body, where it is changed by enzymes into fluorescent chemicals, particularly something called protoporphyrin IX (PPIX). Since glioma cells (tumour cells) absorb more of the active substance and change it more rapidly into PPIX, higher levels accumulate in the cancer cells than in normal tissue.

When illuminated under a blue light of specific wavelength the PPIX in the tumour glows an intense red, while the normal brain tissue appears blue.

The effect of Gliolan® enables the surgeon to see the tumour more clearly during brain surgery and to remove it more accurately, which means sparing healthy brain tissue. The surgeon might decide intraoperatively not to remove all the areas that are glowing, hence leaving some residual tumour. This might be due to proximity with important structures such as vessels or functions (areas that you use to speak or move) that the surgeon cannot remove.

Gliolan® is available as a powder; it is mixed with normal drinking water into a drink. Your nurse will prepare this for you. Gliolan® is given three hours before the start of anaesthesia to ensure that it is absorbed by the cells. If the surgery or anaesthesia is delayed additional doses of this medicine will not be given.

However, if for some reason the surgery is delayed by one or more days, another dose of this medicine can be taken, again three hours before start of anaesthesia.

All medicines can cause side effects, although not everyone will experience them. A member of the team will talk to you about the side effects of Gliolan®. After taking Gliolan® and before the start of anaesthesia, the following side effects may occur: These are uncommon side effects. This means that they are likely to occur in more than one in one thousand patients but less than one in one hundred:

• Nausea – feeling sick
• Photosensitivity – this means that you will be very slightly light sensitive for 24 hours. This means that the day following surgery you will need to avoid direct sunlight. However, the normal ambient light on the surgical ward is perfectly safe.
• Hypotension – low blood pressure. Your blood pressure will be monitored every half an hour after you have taken Gliolan®. Gliolan® should be used with caution in patients with heart disease, or who have had heart disease in the past

You must tell your doctor if you are taking or have recently taken any other medicines particularly: medicines that may cause skin problems when the skin comes under strong light, for example some antibiotics. medicines obtained without prescription such as hypericin or Saint John’s wort extracts. You should not take any such products up to two weeks after you have taken Gliolan®. Any other medicines which may harm the liver should be avoided within 24 hours of taking Gliolan®.

You will be advised about which medicines you must not take. In combination with anaesthesia and tumour resection further side effects may occur.

Side effects that are very common (means that they are likely to occur in more than one patient in ten) are:

• Anaemia – a low red blood cell count
• Thrombocytopaenia – low blood platelet count
• Leukocytosis – high levels of a type of white blood cell called leukocytes Increased levels of liver enzymes in the blood

These changes peak between seven and 14 days after surgery. The changes will completely resolve within a few weeks. Usually, you will not experience any symptoms when these changes occur.

Side effects that are common (means they are likely to occur in more than one of one hundred patients but less than one of ten patients) are:

• Nausea
• Vomiting
• Neurological disorders, such as the inability to move one side of the body (hemiparesis)
• Aphasia – total or partial loss of the ability to use or understand language
• Convulsions – fits or seizures
• Blindness in half the field of vision in one or both eyes
• Thromboembolism - blood clots which may block blood vessels

After taking Gliolan®, your skin will be sensitive to sun light and very bright artificial light for 24 hours. Direct exposure might cause a sun burn-type reaction. There are no scientifically proven ways at present for preventing this, but we can take some very practical measures based on advice from other hospitals where Gliolan® has been used for some time.

Most people receive Gliolan® during the early hours of the morning (between about four and six am). At this time of the day, sunlight will not be a problem. It is recommended that exposure of the skin to direct artificial light in the ward room is avoided; therefore, no over-head lights should be used. Instead, a lamp (not directly shining on you) should be used to light in the room.

When moving you to the operating theatre we will take precautions to avoid exposure to bright artificial lights or sunlight. We may ask you to shield your face with the sheet when passing any windows or brightly lit corridors. In the operating theatre only indirect light is used.

After surgery and in the first 24 hours you will not be put near the windows on the ward. Ideally you will be cared for in a single side room where blinds can be drawn against daylight.

If for some reason your surgery is cancelled after taking Gliolan®, the same principles apply and all precautions to avoid photosensitive reactions are still used.

No. People with the following conditions must not take Gliolan®:

• Hypersensitivity (allergy) to 5-aminolevulvinic acid hydrochloride (5-ALA)
• Porphyria
• Pregnancy (it is not known whether Gliolan® enters breast milk. Breast feeding mothers should not breast feed for 24 hours after treatment with this medicine.) It is most important that you tell your doctor if you have any such conditions or if there is any possibility you may be pregnant.

• European Public Assessment Report (EPAR)
• EMEA – European Medicines Agency, ‘European public assessment report (EPAR) on Gliolan’.
• European Medicines Agency (EMEA), London 2007. medac Patient Information Leaflet, Germany.
• Gliolan® Monograph, July 2008

Neuro-oncology Nurse Specialists
Brain Tumour Unit
National Hospital for Neurology and Neurosurgery
Queen Square
London WC1N 3BG

Direct line: 020 3448 8830
Switchboard: 0845 155 5000 / 020 3456 7890
Email: uclh.braintumourunit@nhs.net