Superior vena cava obstruction (SVCO)
Superior vena cava obstruction (SVCO) is a blockage of a large vein in the chest called the superior vena cava (SVC).
The superior vena cava (SVC) is a large vein that carries blood from the upper half of the body straight to the heart. It lies in the middle of the chest, behind the breast bone (sternum).
Superior vena cava obstruction (SVCO) happens when something blocks the blood flow along the SVC. Because the walls of the SVC are thin, they can easily become squashed (compressed).
Most cases of SVCO are caused by lung cancer. The cancer may press directly on the SVC. Or it may spread to the lymph nodes (glands) nearby, which become swollen.
These are other possible causes:
- Other cancers affecting the lymph nodes in the chest. These include lymphomas and testicular, breast, bowel or gullet (oesophageal) cancers.
- A blood clot forming in the vein and blocking the blood flow. This can happen if you have had a (central line) put into the vein – for example, to give you chemotherapy.
Symptoms of SVCO are caused by the blood flow to the heart being blocked. This causes increased pressure in the head, neck and arms.
Symptoms can develop quickly over a few days or over a few weeks. The first symptom is usually feeling a fullness in the face when you bend over. The other most common symptoms are:
- breathlessness, because of swelling around the windpipe (trachea)
- headaches, which get worse when you lean forward or bend over
- facial swelling, with changes to your complexion
- changes in your eyesight
- a swollen neck
- swollen arms and hands
- visible swollen blue veins on the chest
- feeling dizzy.
It is important to tell your nurse or doctor straight away if you have any of these symptoms. SVCO needs to be treated quickly.
Managing symptoms of SVCO
The symptoms of SVCO can be distressing, but they can usually be quickly controlled.
You may be given oxygen to improve your breathing. You may also have drugs such as:
- painkillers, to ease any pain
- water tablets (diuretics) to get rid of extra fluid
- sedatives, to help you relax.
Your doctor will usually advise bed rest, ideally with the head of the bed raised. If you are breathless, sitting in an upright position might be more comfortable.
Your doctor may give you high doses of a steroid drug called dexamethasone. This will help reduce pressure and swelling around the blood vessel. It will also improve symptoms such as breathlessness. The dose will be reduced gradually after you have had other treatments.
There are different ways of treating SVCO. The treatment you have will depend on how severe the symptoms are and the type of cancer you have.
A stent is a small tube that can be put into the SVC to keep it open. This lets the blood flow through. Your doctor will usually put it in using a local anaesthetic. They may give you a medicine to help you relax. The doctor uses x-ray images to guide the stent into the correct position.
You may have a stent as the first treatment for SVCO. This is because it relieves symptoms quickly. You may also have a stent if SVCO has come back after radiotherapy or chemotherapy.
Stents may not be suitable for people who have a blood clot. Not everyone will be able to have this treatment. Your doctor can tell you if it is suitable for you.
Radiotherapy uses high-energy x-rays to destroy cancer cells, while doing as little harm as possible to normal cells.
Radiotherapy rays are directed at the tumour from outside the body. This is called external radiotherapy. You sometimes have a short course of radiotherapy after SVCO is diagnosed.
Drugs to treat blood clots
Drugs called anti-coagulants, such as heparin and warfarin, can be used to treat SVCO caused by blood clots.
If the blood clot is around a central line, it may be necessary to remove the line. In this situation, your doctors will discuss other cancer treatment options with you.
SVCO can be frightening, as it usually involves:
- a tightening sensation around the chest, head and neck areas.
This may cause many different emotions, including anger, resentment, guilt, anxiety and fear. These are all normal reactions that many people go through.
Everyone has their own way of coping with difficult situations. You may find it helpful to talk to family or friends. Or you may prefer to seek help from people outside your situation. Some people prefer to keep their feelings to themselves. There is no right or wrong way to cope, but help is there if you need it.
Macmillan is also here to support you. If you would like to talk, you can:
Below is a sample of the sources used in our superior vena cava obstruction information. If you would like more information about the sources we use, please contact us at email@example.com
National Institute for Health and Care Excellence (NICE). Lung cancer – Diagnosis and management. Clinical guideline 2019.
Scottish Palliative Care Guidelines. Superior Vena Cava Obstruction. NHSScotland 2019.
This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert medical and health professionals and people living with cancer. It has been approved by Senior Medical Editor, Dr David Gilligan, Consultant Clinical Oncologist.
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